@proceedings {JRN55395, title = {Heritage Raramuri Criollo cattle production as a potential strategy for conservation of black grama in the Chihuahuan Desert}, year = {2022}, month = {3/21/2022}, abstract = {The Chihuahuan desert ecosystem has experienced a decrease in black grama, a perennial grass species with high ecological value for protecting desert topsoil, along with a subsequent increase in mesquite. This trend is thought to be due to several management- and environment-related factors. We compared diet selection of a heritage Raramuri Criollo (RC) vs. Angus-X-Hereford (AH) cattle, typical of the region, using fecal DNA metabarcoding by a commercial laboratory to determine the proportion of black grama and mesquite in samples. RC and AH cows grazed two adjacent pastures (~1100 ha) separately, switched at the mid-point of each period. Rectal fecal samples collected from 10 cows per breed each period. The study was replicated across seasons (growing and dormant) for three consecutive years (240 total fecal samples) in a completely randomized design. Relative abundance of plant species was ranked over the entire study and by season. The MIXED procedure of SAS 9.4 was used to analyze the relative proportions of black grama and mesquite in fecal samples by breed, season, year, and all interactions. Black grama was a more important forage resource than mesquite (ranked 8 vs. 11), particularly during dormancy (ranked 3 vs. 7). When examined by breed, AH had twice the percentage of black grama vs. RC (P<0.05) and even more so during the dormant season (P<0.05). In contrast, RC fecal samples tended to contain a higher percentage of mesquite (P=0.05). Adjustments for dry matter intake (relative to BW) by breed (545 vs. 350 kg mean BW for AH vs. RC respectively) suggests that AH consumed 3.09 fold more black grama while RC consumed 1.59 times more of mesquite. Differences in diet composition documented in this study support the hypothesis that RC cattle could impose a lighter grazing pressure on the black grama community and potentially be utilized as a conservation tool on Chihuahuan Desert rangeland.}, author = {S. Nyamuryekung{\textquoteright}e and Richard E. Estell and D. K. James and Andr{\'e}s F. Cibils and Matthew M. McIntosh and S. Spiegal and S. A. Utsumi} } @article {JRN55269, title = {The Hidden Costs of Land Degradation in US Maize Agriculture}, journal = {Earth{\textquoteright}s Future}, volume = {9}, year = {2021}, month = {02/2021}, pages = {1-19}, chapter = {1}, abstract = {The United States is a world leader in the production of maize and other crops and the agricultural success of the country is directly linked to the intensive use of fertilizers and irrigation. However, even in advanced agricultural systems, soils can become degraded over time due to factors such as soil organic matter (SOM) loss and erosion. Here, we use a series of scenario-based model analyses to show that about one-third of current annual US. N fertilizer use in maize agriculture is used to compensate for the long-term loss of soil fertility through erosion and organic matter loss. This leads to over a half billion dollars per year in extra fertilizer supply costs to US farmers. These results highlight the potential to reduce both the input costs and environmental impacts of agriculture through the restoration of SOM in agricultural soils.}, doi = {https://doi.org/10.1029/2020EF001641}, url = {files/bibliography/21-005.pdf}, author = {Jang, W.S. and J. Neff and Y. Im and Doro, L. and Jeffrey E. Herrick} } @conference {JRN55424, title = {Hacking food waste with 4-H youth}, booktitle = {American Geophysical Union}, year = {2021}, month = {8/4/2021}, abstract = {A team of 4-H Cooperative Extension agents, educational media professionals, and academics at New Mexico State University are collaborating to produce a novel food waste Hackathon for 4-H youth. 4-H (Head, Heart, Hands and Health) is a positive youth development organization with the primary purpose of empowering youth to reach their full potential; a guiding principle of 4-H is learning by doing. The goal of the food waste hackathon is to help youth learn about climate change, and to discover how they can make a difference by designing strategies to motivate sustainable behaviors in their communities. Our team selected food waste as the focus for the hackathon for three main reasons. Firstly, according to the UN Food and Agriculture Organization (FAO), food waste contributes 8 percent of total global greenhouse gas emissions. Included in this total is the wasted energy for growing, harvesting, packaging, and transporting food as well as the methane produced by food entering and rotting in landfills. Secondly, the issue of food waste is closely tied to food security. The FAO estimate that globally, food production must increase by 60 percent by 2050, yet more than 30 percent of food is currently lost or wasted. Thirdly, hacking food waste remains true to the 4-H mission {\textquotedblleft}[to provide] kids with community, mentors, and learning opportunities to develop the skills they need to create positive change in their lives and communities.{\textquotedblright} For this presentation we share our package of Hackathon materials and animations, and we reflect on successes, challenges and opportunities arising from the first event. }, keywords = {4-H Cooperative Extension, 4-H youth, academics, agents, collaborating, educational, food, Hackathon, media, New Mexico State University, novel, produce, professionals, waste}, author = {Caitriana Steele and Amanda Benton and Sierra Cain and Nicole Jacobs and Eva Madrid and Courtney Mitchell and Brittany Sonntag and Peter Skelton and Laura Bittner and Adri{\'a}n Aguirre Mart{\'\i}nez and Matheus Cezarotto and Amy Smith Muise and Barbara Chamberlin} } @conference {JRN55246, title = {Harnessing the power of AI technologies for ecology: Grass recovery in shrub dominated landscapes}, booktitle = {Ecological Society of America}, year = {2020}, month = {08/2020}, address = {Virtual Conference}, abstract = {Many drylands of the world have experienced dramatic changes in vegetation from perennial grasslands to woody plant dominance over the past several centuries. These states are thought to be very stable under current climate as a result of feedbacks between woody plants and soil properties such that grass recovery rarely occurs, and restoration is difficult. When grass recovery occurs, spatiotemporal heterogeneity in recovery patterns at multiple scales makes it challenging to identify the drivers and processes governing those dynamics. New technologies that link big data analytics with computer vision and image processing are promising approaches that can move restoration ecology forward. A 15,708 m2 research site in the northern Chihuahuan Desert was cleared in 1996 and kept barren until 2007. Following treatment and a concurrent multi-year (2004-08) period of above-average rainfall, grasses appeared to recolonize the site. Our objectives were to: 1) analyze the patterns of vegetation change through time from over-head photos and 2) use deep learning and UAV fine-scale imagery to estimate above ground biomass and determine the drivers of grass biomass. To better understand the factors governing this process, we explored historic imagery and hyperspectral and thermal imagery paired with systematic vegetation monitoring and in situ automated sensor networks collecting soil moisture, sediment flux, and local climate data. Our objectives were to 1) explore the patterns of vegetation change through time and 2) use deep learning and a structure from motion approach to estimate above ground biomass. We found that the site transited from bare-soil to increased litter and short-lived forbs followed by the establishment of grasses. The perennial grasses Aristida sp. and Dasyochloa pulchella representing 26\% and 4\% of the foliar cover. Mesquite were also identified across the site and represented much less of the foliar cover (<2\%). In addition, 15 additional species of annual and perennial grasses and forbs, each representing <1\% of the foliar cover, were also identified. Automated classification of the grass recovery site with human guided deep learning was able to rapidly classify and provide volumetric estimates of the study area vegetation. Estimates of above-ground biomass were a function of soil moisture, soil water redistribution, and erosion processes. This approach, offered continuous classification of the composition, and once trained, requires much less time and effort to complete than traditional field methodologies (e.g. quadrat, line point intercept). Due to the continuous surface inputs, this approach may also increase the likelihood of identifying relatively rare, cryptic, or newly occurring species that may go undetected. Poster $\#$88102.}, author = {N. Dylan Burruss and Debra C. Peters} } @conference {JRN55315, title = {Historical shifts in United States manuresheds}, booktitle = {ASA-CSSA-SSSA Annual Meeting Abstracts}, year = {2020}, month = {11/13/2020}, abstract = {Manuresheds, a term concerned with the balance of manure availability for agricultural lands surrounding animal feeding operations, are important to achieve optimal nutrient recycling to promote sustainable agriculture systems. Spatial analytics focused on manuresheds provide locations of nutrient sources/sinks in regards to manure production versus agricultural land needs at a given spatial scale. These spatial analytics have been analyzed at numerous spatial scales (i.e. national, county level, etc.), but have yet to be subject to national level spatio-temporal analytics. Spatio-temporal analytics focused on the redistribution of manure-based nutrients (phosphorus and nitrogen) at the county-level will provide information regarding portions of the U.S. experiencing growth/shrinking of source (overabundance of nutrients for given agricultural lands) and sink (requires more nutrients to meet agricultural land needs) hotspots. Thus, this research aims to apply spatio-temporal manureshed analytics for years 1987 to 2017 across 3,109 counties. This retrospective approach will establish an understanding of the national-scale patterns of manuresheds that will better inform future needs for nutrient management. Understanding these spatio-temporal patterns will provide focus areas in which sustainable agricultural systems can be improved.}, keywords = {analytics, historical shifts, manureshed, spatio-temporal, United States manuresheds}, author = {Colton K Flynn and S. Spiegal and Douglas Smith and Peter J. A. Kleinman} } @article {JRN55308, title = {Harnessing AI to transform agriculture and inform agricultural research}, journal = {IEEE IT Professional}, volume = {22}, year = {2020}, month = {05/01/2020}, pages = { 16 - 21}, abstract = {We provide an overview of the Special Issue on current advances, challenges, and opportunities for AI technologies in agriculture. We illustrate the potential of AI using four major components of the food system: production, distribution, consumption, and uncertainty. We recognize that the transformation of agriculture will require new tools to more precisely manage fields to increase production while minimizing the environmental risk to water and air quality. Combining AI with other technologies will be needed to provide effective production management strategies for a given combination of soil, climate, pest complexes, and vegetation. New methods will be needed to determine production limitations, and effective management options. The agricultural enterprise is prime for the use of AI and other technologies if they can be adapted for the unique characteristics of agroecosystems, including variability and directional changes in climate and other global change drivers as well as novel management and policy decisions, and economic market volatility.}, keywords = {agriculture, artificial intelligence, Immune system, meteorology, production, Uncertainty}, doi = {10.1109/MITP.2020.2986124}, url = {files/bibliography/20-038.pdf}, author = {Debra C. Peters and Adam Rivers and J. Hatfield and Danielle G. Lemay and Simon Liu and Bruno Basso} } @conference {JRN55245, title = {Harnessing the power of AI technologies for ecology: The knowledge learning analysis system (KLAS) for spatially-distributed, continuous ecological data}, booktitle = {Ecological Society of America}, year = {2020}, month = {08/2020}, address = {Virtual Conference}, abstract = {Background/Question/Methods Sensors are increasingly being used to capture information about biotic processes and environmental conditions at finer spatial and temporal resolutions across broader spatial extents than possible from data collected manually. This sensor-based information is leading to new insights about ecological systems through the integration of data across scales, disciplinary interests, and levels of organization. However, sensors can also produce large volumes of different types of data at higher frequencies for more spatially-distributed locations than ecologists are used to handling or managing. Artificial intelligence (AI) technologies provide one approach to effectively distilling, managing, and analyzing these large and diverse amounts of data to be used for ecological problems. Our objectives were to develop an AI system to evaluate and learn from streaming data that: (1) would automate the QA/QC of sensor data, and (2) would be sufficiently flexible to account for changes in climate through time. We developed an AI system in R and MatLab combined with the GCE Toolbox. We analyzed sensor data from 15 meteorological stations spatially-distributed at the Jornada USDA-LTER site in southern New Mexico. We then tested the scalability of our AI system by applying it to an additional 60 spatially-distributed meteorological stations locations at the Jornada, and to primary production data. Results/Conclusions; Our AI system effectively assimilated and analyzed large volumes of streaming data from meteorological stations, and provided level one QA/QC data for all 15 locations. The data were uploaded to a national data repository (EDI) with ecological metadata within one day following data collection. These metrics contrast with our previous manual approach to checking and correcting the data that resulted in monthly time lags before uploading the data. The AI system was successfully applied to an additional 60 locations with meteorological stations, and to primary production data. Given the automated data collection and AI computational process, adding more stations did not increase the time required for checking and uploading the data to EDI, and the errors associated with the data did not increase. Recent additions to our approach to identifying outliers from extreme values based on comparisons with nearby locations result in an approach that is sufficiently flexible to account for changes in climate through time. Our AI system is a dynamic approach that can be applied to other data types, locations, and ecosystems where non-stationarity through time is important. Poster $\#$85379.}, author = {Debra C. Peters and Geovany Ramirez and John P. Anderson and Heather Savoy and Haitao Huang} } @conference {JRN55249, title = {Hidden biodiversity: How soil seed banks vary across ecological sites and states in the Chihuahuan Desert}, booktitle = {Ecological Society of America}, year = {2020}, month = {08/2020}, address = {Virtual Conference}, abstract = {Background/Question/Methods: Ecological state transitions involving the encroachment of shrubs and loss of herbaceous species are common and highly persistent in the Chihuahuan Desert, even when disturbances are reduced and shrubs are removed. The existing seed bank in these soils is poorly documented and seed bank limitation may constrain the recovery of historical herbaceous communities. Seed bank quantification could enhance our understanding of future shift implications in ecological sites and states. Addressing these core issues of how biodiversity may change in drylands across degradation levels, three primary questions were posited: What can the seed bank tell us about biodiversity in the Chihuahuan Desert? How does the seed bank differ by ecological site and the different states (levels of degradation) in those sites? What does the seed bank tell us about grassland to shrubland shifts? From 2015 to 2017 a germinable seed bank study was conducted by collecting a total of 258 soil samples (each measuring 796 cm3) from randomly selected sites on 190,000 acres of the Jornada Experimental Range in Southern New Mexico. Collection sites were stratified by ecological states within each of the ten ecological sites found on the range. Over a two-year period, these samples were provided ample water and monitored in greenhouse conditions. Results/Conclusions: The soil yielded 12,777 seedlings from 159 species of vascular plants. Mean values of germinated seed for ecological sites and states exhibited high biodiversity. Species identified were mostly native perennials, many of them not displayed in their aboveground vegetative counterparts. Seed banks in the Chihuahuan desert have limited ability to express themselves as degradation progresses through ecological states and with climatic shifts. Biodiversity remains in degraded sites as soil seed caches. Seeding may not be necessary for restoration efforts. Poster $\#$86481.}, author = {Kirsten B. Romig and D. K. James and Connie J. Maxwell and Joel R. Brown and Brandon T Bestelmeyer and Kris Havstad and S. W. Salley and Akasha M. Faist} } @article {JRN55184, title = {Herbivory Effects on Ephedra spp. in the Chihuahuan Desert}, journal = {Open Journal of Ecology}, volume = {10}, year = {2020}, month = { February 2020}, pages = { 37-44 }, abstract = {

Two species of Ephedra: E. trifurca and E. torreyana inhabit shrub and grassland habitats in the northern Chihuahuan Desert. E. torreyana is limited to black grama grasslands where grasses are taller than the shrub. E. torreyana is heavily browsed by vertebrates and E. trifurca is browsed during some years. We established an experiment with cylindrical exclosures that excluded rabbits and rodents, rabbits but accessible to rodents, for comparison with E. torreyana plants available to all herbivores. Plants accessible to all vertebrate herbivores were significantly smaller with shorter stem lengths than plants in exclosures. We concluded that E. torreyana in black grama grassland are largely hidden from vertebrate herbivores and that intense herbivory reflects the degraded state of the study site which makes the E. torreyana evergreen shrubs apparent to vertebrates.

}, keywords = {Desert Cottontail Rabbits (Sylvilagus auduboni), desertification, Ephedra torreyana, Ephedra trifurca, Exclosures, Jackrabbits (Lepus californicus)}, doi = {10.4236/oje.2020.102003}, url = {files/bibliography/20-007.pdf}, author = {Walter G. Whitford and Yosef Steinberger} } @conference {JRN54937, title = {How do Progressively Warming Temperatures Impact Runoff Volume and Streamflow Timing in Rio Grande Watersheds?}, booktitle = {86th Annual Western Snow Conference}, year = {2018}, month = {04/2018}, address = {Albuquerque, New Mexico}, abstract = {

We used a revised version of the Snowmelt Runoff Model (SRMc21) to simulate the impact of progressively warming temperatures on snowmelt runoff in four headwaters catchments of the San Juan Mountains (Alamosa, Chama, Conejos and Del Norte) draining to the Rio Grande. MODIS snow cover was used to generate depletion curves, which are used in SRM, along with parameters adjustable to fit measured and simulated runoff. For each watershed, SRMc21 was first used to simulate daily streamflow with a high agreement between measured and computed runoff (R2=0.92 to 0.96).\  SRMc21 was then used to simulate the impacts of sequentially increasing temperatures (1, 2, 3 and 4C). In each watershed total annual volume progressively declined with increasing temperature (mean decline of 5\% with +1C, 8\% with +2C, 10\% with +3C and 13\% with +4C temperature increase). For each watershed, the center of volume date shifted progressively earlier with each increase in temperature. Center of volume was one week earlier with a mean temperature increase of 1C and up to one month earlier with an increase of 4C. The ability to shift operational and institutional frameworks (such as water rights) to accommodate shifts in streamflow timing should be an area of future analysis. The simulated temperature increases are within CMIP5 multi-model mean projections for the region. By midcentury (2040-2069) the moderate scenarios (RCP 4.5) project a mean temperature increase of 2.4C whereas the high-emissions scenarios (RCP 8.5) project a mean temperature increase of 3.3C. End of century (2070-2099) moderate scenarios project an average increase of 3.0C whereas high-emissions scenarios project a 5.3C increase in mean temperature for this region.

}, author = {Emile H. Elias and Ryann Smith and Caitriana Steele and A. Rango} } @proceedings {JRN54856, title = {High quality data: An evaluation of AIM data quality and data quality procedures}, volume = {January 28-February 2, 2018}, year = {2018}, month = {01/28/2018}, publisher = {Society for Range Managment}, address = {Reno, Nevada}, abstract = {

The goal of every monitoring program is to collect high-quality data which can then be used to provide information to decision makers. The Bureau of Land Management (BLM) Assessment, Inventory, and Monitoring (AIM) program is one such data set which provides rangeland status, condition, and trend information across BLM rangelands. These points represent aquatic and terrestrial resources across the western United States and Alaska. To date there are over 18,000 terrestrial points and 1400 aquatic points. While these data were collected for specific objectives, they are available for use by other BLM resource managers, other agencies and academic institutions to meet multiple resource questions and objectives. The broad utility of these data is due to the core methods and protocols employed during data collection as well as the quality assurance and quality control protocols employed by the AIM program. Here we evaluate the steps AIM takes to ensure quality, including project planning, core method implementation, observer training and calibration, electronic data capture, automated and manual data checks, and database structures. We describe the terrestrial database, TerrADat, and aquatic database, AquADat, and how these databases can be accessed by non-BLM users. Known quality procedures and evaluation measures improve the AIM data and can help users understand how and when the AIM data or data procedures may be useful to current and future applications.

}, author = {Sarah McCord and Sarah Burnett and Nicole Cappuccio and Jennifer Courtright} } @conference {JRN54936, title = {Harnessing the power of big data in ecology by machine learning}, booktitle = {10th Internationl Conference on Ecological Informatics}, year = {2018}, month = {09/2018}, address = {Jena, Germany}, abstract = {

My talk will be about a Trans-Disciplinary Data-Model Integration (TDMI) approach that focuses on spatio-temporal modeling and cross-scale interactions, and employs interactive machine learning strategies. Applied to ecological problems, my approach integrates knowledge and data on: (1) biological processes, (2) spatial heterogeneity in the land surface template, and (3) variability in environmental drivers using data and knowledge drawn from multiple lines of evidence (i.e., observations, experimental manipulations, analytical and numerical models, products from imagery, conceptual model reasoning, theory). I will apply this approach to a suite of increasingly complex ecologically-relevant problems, and will show how the framework can be linked with a Data Science Integration System (DSIS) to allow more complex questions to be addressed in the future.

}, author = {Debra C. Peters} } @conference {JRN55061, title = {How to detect change in aeolian sediment transport}, booktitle = {International Conference on Aeolian Research}, year = {2018}, month = {06/2018}, address = {Bordeaux, France}, abstract = {

The detection of change in aeolian sediment transport is key to explaining cause. For example, anthropogenic land use and land cover change (LULCC) influence global rates of wind erosion and dust emission. However, current approaches to measuring wind erosion and dust emission are typically highly uncertain, because they inadequately account for the large spatial and temporal variation in aeolian sediment transport. Field measurements need to reduce uncertainty sufficiently to enable change to be detected at some specified confidence level. Here, we use field measurements of aeolian sediment transport to show (Figure 1) that: i) the spatial variance in aeolian sediment transport may be many times larger than the temporal variance depending on the land surface aerodynamics and sediment supply; and ii) too few samplers, or poorly positioned (biased, e.g., by avoiding vegetation) samplers inflate uncertainty causing change in aeolian sediment transport to be undetectable. The straightforward application of an unbiased sampling design combined with a rigorous statistical framework enables minimum detectable change over time in aeolian sediment transport responding to e.g., land use and management across land cover types. We examine how robust field measurements can be combined with new modelling approaches that resolve the spatial variation in transport controls to improve dust model sensitivity and reduce uncertainty in assessments of the impacts of LULCC.

}, author = {Nicholas Webb and A. Chappell and Justin Van Zee and Brandon Edwards and D. K. James} } @article {JRN54661, title = {Hyper-temporal remote sensing for digital soil mapping: Characterizing soil-vegetation response to climatic variability}, journal = {Geoderma}, volume = {285:94-109}, year = {2017}, month = {01/2017}, abstract = {
Indices derived from remotely-sensed imagery are commonly used to predict soil properties with digital soil mapping (DSM) techniques. The use of images from single dates or a small number of dates is most common for DSM; however, selection of the appropriate images is complicated by temporal variability in land surface spectral properties. We argue that hyper-temporal remote sensing (RS) (i.e., hundreds of images) can provide novel insights into soil spatial variability by quantifying the temporal response of land surface spectral properties. This temporal response provides a spectral {\textquoteleft}fingerprint{\textquoteright} of the soil-vegetation relationship which is directly related to a range of soil properties. To evaluate the hyper-temporal RS approach, this study first reviewed and synthesized, within the context of temporal variability, previous research that has used RS imagery for DSM. From this analysis we developed a conceptual framework for understanding the soil-vegetation-climate relationship discernable with hyper-temporal RS, which encapsulates both intra- and inter-annual variability. Finally, we demonstrate the utility of this approach by presenting a case study in a semiarid landscape of southeastern Arizona, USA; where surface soil texture and coarse fragment classes were predicted using a 29 year time series of normalized difference vegetation index (NDVI) from Landsat TM data and modeled using support vector machine (SVM) classification. Results from the case study show that SVM classification using hyper-temporal RS imagery was effective in modeling both soil texture and coarse fragment classes, where both variables were 60\% percent correctly classified (PCC). In this semiarid ecosystem, variability in precipitation at short time scales (i.e., \<6 weeks) was the dominant driver of vegetation spectral variability, with maximum variability corresponding to short-term transitions between climatic states. These short-term transitions between climatic states corresponded to the RS scenes with the highest variable importance in our SMV models, confirming the importance of spectral variability in predicting soil texture and coarse fragment classes. Results from the case study demonstrate the efficacy of the hyper-temporal RS approach in predicting soil properties and highlights how hyper-temporal RS can improve current methods of soil mapping efforts through its ability to characterize subtle changes in RS spectra relating to variation in soil properties.
}, doi = {dx.doi.org/10.1016/j.geoderma.2016.09.024}, url = {files/bibliography/17-001.pdf}, author = {Jonathan Maynard and Matthew Levi} } @article {JRN55177, title = {History and Applications of Dust Devil Studies}, journal = {Space Science Reviews}, volume = {203}, year = {2016}, month = {April 2016}, abstract = {

Studies of dust devils, and their impact on society, are reviewed. Dust devils have been noted since antiquity, and have been documented in many countries, as well as on the planet Mars. As time-variable vortex entities, they have become a cultural motif. Three major stimuli of dust devil research are identified, nuclear testing, terrestrial climate studies, and perhaps most significantly, Mars research. Dust devils present an occasional safety hazard to light structures and have caused several deaths.

}, keywords = {applications, climate, Dust Devil, history, nuclear, safety, terestrial}, doi = {10.1007/s11214-016-0239-2}, url = {files/bibliography/16-040_0.pdf}, author = {Ralph D. Lorenz and Matthew R. Balme and Zhaolin Gu and Henrik Kahanp{\"a}{\"a} and Martina Klose and Michael V. Kurgansky and Manish R. Patel and Dennis Reiss and Angelo Pio Rossi and Aymeric Spiga and Tetsuya Takemi and Wei Wei} } @conference {JRN54406, title = {A hyper-temporal remote sensing protocol for detecting ecosystem disturbance, classifying ecological state, and assessing soil resilience}, booktitle = { 2015 Soil Science Society of America Annual Meeting}, year = {2015}, month = {11/2015}, publisher = {SSSA}, organization = {SSSA}, address = {Minneapolis, MN}, abstract = {

yper-temporal remote sensing is capable of detecting detailed information on vegetation dynamics relating to plant functional types (PFT), a useful proxy for estimating soil physical and chemical properties. A central concept of PFT is that plant morphological and physiological adaptations are linked in predictable ways by resource limitation, responses to disturbance, and edaphic factors. Consequently, the main objectives of this study were to evaluate the ability of hyper-temporal remotely sensed imagery to (i) classify PFT relating to different ecological states, (ii) quantify the magnitude and timing of significant ecosystem changes, and (iii) assess the dominant soil properties that impart ecosystem resilience within a semi-arid rangeland ecosystem. The modified soil adjusted vegetation index (MSAVI), derived from Landsat imagery, was compiled for the period between 2000 and 2012 (16-day frequency), resulting in 269 observations per 30-m pixel. Hierarchical cluster analysis was performed on the hyper-temporal image stack, delineating areas with similar ecological states based on temporal variability within each time-series. The average temporal signal from each cluster was then decomposed into seasonal and long-term trend components using the Breaks For Additive Seasonal and Trend (BFAST) model, which further identified the direction, magnitude and timing of significant deviations from modeled trends. Significant breaks, in combination with ancillary environmental data, were used to evaluate the resistance and resilience of each ecological state. Soil properties maps (0-50 cm), created from gridded SSURGO data, provided explanatory variables in an ordination and variance partitioning analysis to determine which key soil properties correspond to identified patterns of ecosystem resilience. Results from this study showed that physical soil properties (e.g., texture, water holding capacity) were the most significant in explaining resilience patterns. Furthermore, this study demonstrates the power and utility of this approach in delineating ecological states, interpreting temporal drivers of change, and identifying edaphic controls on ecosystem resilience.

}, author = {Jonathan Maynard and Jason W. Karl} } @article {JRN54394, title = {Hyperspectral surface reflectance data detect low moisture status of pecan orchards during flood irrigation }, journal = {Journal of the American Society for Horticultural Science}, volume = {140}, year = {2015}, month = {09/2015}, pages = {449-458}, chapter = {449}, abstract = {

For large fields, remote sensing might permit plant low moisture status to be detected early, and this may improve drought detection and monitoring. The objective of this study was to determine whether canopy and soil surface reflectance data derived from a handheld spectroradiometer can detect moisture status assessed using midday stem water potential (csmd) in pecan (Carya illinoinensis) during cyclic flood irrigations. We conducted the study simultaneously on two mature pecan orchards, a sandy loam (La Mancha) and a clay loam (Leyendecker) soil. We were particularly interested in detecting moisture status in the L0.90 to L1.5 MPa csmd range because our previous studies indicated this was the critical range for irrigating pecan. Midday stem water potential, photosynthesis (A) and canopy and soil surface reflectance measurements were taken over the course of irrigation dry-down cycles at csmd levels of L0.40 to L0.85 MPa (well watered) and L0.9 to L1.5 MPa (water deficit). The decline in A averaged 34\% in La Mancha and 25\% in Leyendecker orchard when csmd ranged from L0.9 to L1.5 MPa. Average canopy surface reflectance of well-watered trees (csmd L0.4 to L0.85 MPa) was significantly higher than the same trees experiencing water deficits (csmd L0.9 to L1.5 MPa) within the 350- to 2500-nm bands range. Conversely, soil surface reflectance of well-watered trees was lower than water deficit overall bands. At both orchards, coefficiet of determinations between csmd and all soil and canopy bands and surface reflectance indices were less than 0.62. But discriminant analysis models derived from combining soil and canopy reflectance data of well-watered and water-deficit trees had high classification accuracy (overall and cross-validation classification accuracy \>80\%). A discriminant model that included triangular vegetation index (TVI), photochemical reflectance index (PRI), and normalized soil moisture index (NSMI) had 85\% overall accuracy and 82\% cross-validation accuracy at La Mancha orchard. At Leyendecker, either a discriminant model weighted with two soil bands (690 and 2430 nm) or a discriminant model that used PRI and soil band 2430 nm had an overall classification and cross-validation accuracy of 99\%. In summary, the results presented here suggest that canopy and soil hyperspectral data derived from a handheld spectroradiometer hold promise for discerning the csmd of pecan orchards subjected to flood irrigation.

}, url = {/files/bibliography/15-020.pdf}, author = {Othman, Yahia and Caitriana Steele and D. VanLeeuwen and St. Hilaire, Rolston} } @conference {JRN54413, title = {Historical perspectives and recommendations for revision of Agricultural Handbook 296}, booktitle = {2015 National Cooperative Soil Survey National Conference}, year = {2015}, month = {06/2015}, address = {Duluth, MN}, abstract = {

Major Land Resource Areas (MLRAs) are designed to support the development and coordination of soil and water conservation programs by the NRCS, with the primary document describing MLRA being Agricultural Handbook $\#$296 (1965, 1978, 1981, and 2006). While the most recent edition of the handbook was released in 2006, many of the geographic boundaries consistently mimic historic map products of generalized regional and national soil-survey maps (some dating back to the 1930s). Furthermore, the underlying concepts and technologies used to build MLRA geography predate adoption of present-day ecological approaches to resource management and conservation. Thus a need has arisen to better develop and define the concepts allowing for {\textquotedblleft}unique and defensible{\textquotedblright} MLRA geography against neighboring MLRAs. For example, an MLRA must be confined within a physiographic province, contain unique ecological sites/soil map units from its adjoining resource areas, and should incorporate advances in soil climate modeling and data-driven digital soil mapping techniques into MLRA concepts. In preparation for revising the Agricultural Handbook $\#$296, the National Ecological Site Team at the Jornada Experimental Range has underway the compiling of an extensive geographic database of land use, elevation, topography, climate, water resources, potential natural vegetation, and soils. Our approach to developing data-driven MLRA is to use modern geospatial techniques in order to develop a more robust approach to resource area concepts. Our presentation will present the historical development of MLRA concepts and provide recommendations for a national framework in which to create more uniform standards and definitions of MLRA relevant to present day resource and conservation needs.

}, author = {S. W. Salley and Peg Gronemeyer and Curtis Talbot and Joel R. Brown} } @article {JRN54426, title = {Historical Perspectives and Recommendations for revision of the Agricultural Handbook 296 }, year = {2015}, month = {03/2015}, abstract = {

While the most recent edition of Agriculture Handbook 296 was released in 2006, many of the geographic boundaries consistently mimic historic map products of generalized regional and national soil-survey maps (some dating back to the 1930s). Furthermore, the underlying concepts and technologies used to build MLRA geography predate adoption of present-day ecological approaches to resource management and conservation. The National Ecological Site Team at the Jornada has begun compiling a national database of physiography, geology, climate, water resources, soils, and land-use to aid in development a data-driven approach to MLRA. We \ will present the general historical development of MLRA and provide recommendations for revisions of Agricultural Handbook 296.\  www.youtube.com/watch?v=uVTegM8vk5I.

}, author = {S. W. Salley and Curtis Talbot and Joel R. Brown} } @article {JRN53951, title = {Harnessing the power of big data: infusing the scientific method with machine learning to transform ecology}, journal = {Ecosphere}, volume = {5}, year = {2014}, month = {06/2014}, chapter = {Article 67}, abstract = {

Most efforts to harness the power of big data for ecology and environmental sciences focus on data and metadata sharing, standardization, and accuracy. However, many scientists have not accepted the data deluge as an integral part of their research because the current scientific method is not scalable to large, complex datasets. Here, we explain how integrating a dataintensive, machine learning approach with a hypothesis-driven, mechanistic approach can lead to a novel knowledge, learning, analysis system (KLAS) for discovery and problem solving. Machine learning leads to more efficient, user-friendly analytics as the streams of data increase while hypothesis-driven decisions lead to the strategic design of experiments to fill knowledge gaps and to elucidate mechanisms. KLAS will transform ecology and environmental sciences by shortening the time lag between individual discoveries and leaps in knowledge by the scientific community, and will lead to paradigm shifts predicated on open access data and analytics in a machine learning environment.

}, keywords = {analytics, data deluge, long-term data, machine learning, open data, paradigm shifts}, doi = {10.1890/ES13-00359.1}, url = {/files/bibliography/14-013.pdf}, author = {Debra C. Peters and Kris Havstad and Cushing, Judy and Craig Tweedie and Fuentes, Olac and Villanueva-Rosales, Natalia} } @article {JRN53957, title = {High-resolution characterization of a semiarid watershed: Implications on evapotranspiration estimates}, journal = {Journal of Hydrology}, volume = {509}, year = {2014}, month = {02/2014}, pages = {306-319}, chapter = {306}, abstract = {

The North American monsoon (NAM) contributes roughly half of the annual precipitation in the Chihuahuan Desert from July to September. Relatively frequent, intense storms increase soil moisture and lead to ephemeral runoff. Quantifying these processes, however, is difficult due to the sparse nature of existing observations. This study presents results from a dense network of rain gauges, soil probes, channel flumes, and an eddy covariance tower in a small watershed of the Jornada Experimental Range. Using this network, the temporal and spatial variability of soil conditions and channel runoff were assessed from June 2010 to September 2011. In addition, tower measurements were used to quantify the seasonal, monthly and event-scale changes in land-atmosphere states and fluxes. Results from this study indicate a strong seasonality in water and energy fluxes, with a reduction in the Bowen ratio (B) from winter (B=14) to summer (B=3.3). This reduction was tied to higher shallow soil moisture (q) availability during the summer (q=0.040 m3/m3) as compared to winter (q=0.004 m3/m359). Four consecutive rainfall-runoff events during the NAM were used to quantify the soil moisture and channel runoff responses and how water availability impacted land-atmosphere fluxes. The network also allowed comparisons of several approaches to estimate evapotranspiration (ET).\  Using a water balance residual approach, a more accurate ET estimate was obtained when distributed measurements were used, as opposed to single site measurements at the tower. In addition, the spatially-varied soil moisture data yielded a more reasonable daily relation between ET and q, an important parameterization in many hydrologic models. These analyses illustrate the value of high-resolution sampling in small watersheds to characterize hydrologic processes.

}, keywords = {environmental sensor network, evapotranspiration, mixed shrubland, soil moisture, unmanned aerial vehicle, watershed hydrology}, doi = {10.1016/j.jhydrol.2013.11.047}, url = {/files/bibliography/14-014.pdf}, author = {Ryan Templeton and Enrique Vivoni and Mendez-Barroso, Luis A. and Nicole Pierini and C.A. Anderson and A. Rango and Andrea S. Laliberte and R.L. Scott} } @inbook {JRN52663, title = {History and organization of the EcoTrends project}, booktitle = {Long-Term Trends in Ecological Systems: A Basis for Understanding Responses to Global Change}, year = {2013}, pages = {21-27}, publisher = {National Technical Information Services}, organization = {National Technical Information Services}, chapter = {2}, address = {Springfield, Virginia}, abstract = {

This chapter describes the internal organization and timeline of the EcoTrends Project, from which the data and recommendations in the subsequent chapters are generated.\  The project began in 2004, and its organizational structure expanded over the next six years to include many activities and dozens of individuals from six major groups.\  The six major groups are the EcoTrends Project Office, the EcoTrends Editorial Committee, the EcoTrends Technical Committee, participating site scientists, information managers, and technical staff, the Long Term Ecological Research Network Office, and the EcoTrends Socioeconomic Working Group.\  The major activities occurred from 2004 to 2010, when this book is completed, are listed in the chapter.

}, keywords = {atmospheric chemistry, climate change, cross-site comparisons, disturbance, ecological response, ecology, ecosystem, EcoTrends, experimental forests, global change, human demography, human population growth, Long Term Ecological Research (LTER), long-term datasets, precipitation, rangeland, rangeland research stations, surface water chemistry}, url = {/files/bibliography/13-029-2.pdf}, author = {C. Laney and Debra C. Peters and Baker, K. S.} } @inbook {49874, title = {Is the historical range of variation relevant to rangeland management?}, booktitle = {Historical Environmental Variation in Conservation and Natural Resources Management: Past, Present, and Future}, year = {2012}, pages = {289-296}, publisher = {Wiley-Blackwell}, organization = {Wiley-Blackwell}, chapter = {21}, abstract = {

Rangelands occupy about 40\% of the Earth{\textquoteright}s terrestrial surface, comprising grasslands, shrublands, and deserts (Havstad et al., 2007). Over a billion people live in rangelands, engaged primarily in pastoralism and limited crop agriculture for subsistence. Rangelands can be ideal coupled human-natural systems. They can harbor great biodiversity and beauty, while at the same time providing food and soul-enriching connections between humans and the natural world. Resources can be exploited in grazing ecosystems such that most historical or natural elements are sustained (Brown and MacDonald 1995). The sustainable partnership of people and rangelands, however, has not been easy in many places. Recent estimates suggest that a large proportion of rangelands has become degraded, where degradation includes effects ranging from shifts in species composition to soil loss. These changes have been harmful for both biodiversity and human welfare. Worse, rangeland degradation is expected to accelerate with increases in human population and regional aridification (Millenium Ecosystem Assessment 2005). In this essay, I offer some thoughts on the utility of historical range of variation concepts (hereafter HRV) to address the core problem of managing change in rangelands. I argue that, although HRV has value, it is not by itself a firm basis for rangeland management.

}, keywords = {book, chapter, conservation, environmental variation, historical natural resource management, report}, doi = {10.1002/9781118329726.ch21}, author = {Brandon T Bestelmeyer}, editor = {J.A. Wiens and Regan, C. and Hayward, G. and Safford, H.} } @article {49876, title = {Hierarchial analysis of vegetation dynamics over 71 years: soil-rainfall interactions in a Chihuahuan Desert ecosystem}, journal = {Ecological Applications}, volume = {22}, year = {2012}, month = {04/2012}, pages = {909-926}, chapter = {909}, abstract = {

Proliferation of woody plants in grasslands and savannas is a persistent problem globally. This widely observed shift from grass to shrub dominance in rangelands worldwide has been heterogeneous in space and time largely due to cross-scale interactions among soils, climate, and land-use history. Our objective was to use a hierarchical framework to evaluate the relationship between spatial patterns in soil properties and long-term shrub dynamics in the northern Chihuahuan Desert of New Mexico, USA. To meet this objective, shrub patch dynamics from 1937 to 2008 were characterized at patch and landscape scales using historical imagery and a recent digital soils map. Effects of annual precipitation on patch dynamics on two soils revealed strong correlations between shrub growth on deep sandy soils and above-average rainfall years (r = 0.671, P = 0.034) and shrub colonization and below-average rainfall years on shallow sandy soils (r = 0.705, P = 0.023). Patch-level analysis of demographic patterns revealed significant differences between shrub patches on deep and shallow sandy soils during periods of above- and below-average rainfall. Both deep and shallow sandy soils exhibited low shrub cover in 1937 (1.0\% {\textpm} 2.3\% and 0.3\% {\textpm} 1.3\%, respectively [mean {\textpm} SD]) and were characterized by colonization or appearance of new patches until 1960. However, different demographic responses to the cessation of severe drought on the two soils and increased frequency of wet years after 1960 have resulted in very different endpoints. In 2008 a shrubland occupied the deep sandy soils with cover at 19.8\% {\textpm} 9.1\%, while a shrub-dominated grassland occurred on the shallow sandy soils with cover at 9.3\% {\textpm} 7.2\%. Present-day shrub vegetation constitutes a shifting mosaic marked by the coexistence of patches at different stages of development. Management implications of this long-term multi-scale assessment of vegetation dynamics support the notion that soil properties may constrain grassland remediation. Such efforts on sandy soils should be focused on sites characterized by near-surface water-holding capacity, as those lacking available water-holding capacity in the shallow root zone pose challenges to grass recovery and survival.

}, keywords = {aerial photography, Chihuahuan Desert, cross-scale linkages, ecological-state mapping, hierarchy theory, Jornada Basin LTER, New Mexico USA, object-based change detection, petrocalcic soil, prosopis glandulosa, shrub patch dynamics, shrub proliferation, soil depth}, doi = {10.1890/11-1193.1}, url = {/files/bibliography/12-026.pdf}, author = {Dawn M. Browning and Danielle Duni and Andrea S. Laliberte and A. Rango} } @article {49886, title = {A holistic strategy for adaptive land management}, journal = {Journal of Soil and Water Conservation}, volume = {67}, year = {2012}, month = {08/0/2012}, pages = {105A-113A}, chapter = {105A}, abstract = {

Adaptive management is widely applied to natural resources management. Adaptive management can be generally defined as an iterative decision-making process that incorporates formulation of management objectives, actions designed to address these objectives, monitoring of results, and repeated adaptation of management until desired results are achieved. In this paper, we argue for a more holistic and systematic approach to adaptive management. We define holistic, adaptive, land management (HALM) as a refinement of adaptive management that requires (1) a process-based understanding of ecosystem dynamics and ecological mechanisms, (2) a willingness and ability to identify and consider all possible management alternatives, (3) rigorous monitoring of management effects, and (4) constant adaptation of management based on monitoring data and associated observations.

}, doi = {10.2489/jswc.67.4.105A}, url = {/files/bibliography/12-018.pdf}, author = {Jeffrey E. Herrick and Danielle Duni and D.A. Pyke and Brandon T Bestelmeyer and S.A. Wills and Joel R. Brown and Jason W. Karl and Kris Havstad} } @article {49898, title = {How can science be general, yet specific: The conundrum of rangeland science in the 21st Century}, journal = {Rangeland Ecology and Management}, volume = {65}, year = {2012}, month = {11/2012}, pages = {613-622}, chapter = {613}, abstract = {

A critical challenge for range scientists is to provide input to management decisions for land units where little or no data exist. The disciplines of range science, basic ecology, and global ecology use different perspectives and approaches with different levels of detail to extrapolate information and understanding from well-studied locations to other land units. However, these traditional approaches are expected to be insufficient in the future as both human and climatic drivers change in magnitude and direction, spatial heterogeneity in land cover and its use increases, and rangelands become increasingly connected at local to global scales by flows of materials, people, and information. Here we argue that to overcome limitations of each individual discipline, and to effectively address future rangeland problems, scientists will need to successfully integrate these disciplines in novel ways. The objectives of this paper are: (1) to describe the background, historical development, and limitations of current approaches, (2) to describe an integrated approach that takes advantage of the strengths and minimizes the weaknesses of each individual approach, and (3) to discuss the challenges and implications of this integrated approach to the future of range science when climate and human drivers are non-stationary. This integration will be critical for applying range science to the management of specific land units, and will contribute to and benefit from the development of general ecological principles as well as to addressing problems facing society at regional, continental, and global scales.

}, keywords = {downscaling, extrapolation, global ecology, integration, nonstationarity, spatial heterogeneity}, doi = {10.2111/REM-D-11-00178.1}, url = {/files/bibliography/12-034.pdf}, author = {Debra C. Peters and Jayne Belnap and J. Ludwig and S.L. Collins and Paruelo, J. and Hoffman, M. Timm and Kris Havstad} } @proceedings {JRN54530, title = {Hydrology with unmanned aerial vehicles (UAVs)}, volume = {p.7, $\#$1228817}, year = {2011}, month = {02/2012}, publisher = {AGU Chapman Confrence on REmoe Sensing of the Terrestrail Water Cycle}, address = {Kona, Hawaii}, abstract = {Hydrologic remote sensing currently depends on expensive and infrequent aircraft observations for validation of operational satellite products, typically conducted during field campaigns that also include ground-based measurements. With the advent of new, hydrologically-relevant satellite missions, such as the Soil Moisture Active Passive (SMAP) mission, there is a pressing need for more frequent, less expensive techniques for validating satellite retrievals that can be integrated with ground sensor networks. Unmanned Aerial Vehicles (UAVs) provide intermediate to high resolutions and spatial coverage that can fill the gap between satellite observations and ground-based sensors at resolutions superior to manned aircraft data. Their use in the hydrologic community for obtaining variables that can serve as input or validation fields for hydrologic models is an emerging area that deserves greater attention. The development of these tools for field to regional-scale hydrologic sensing and modeling is further punctuated by the potential for reduced long-term funding for satellite and manned aircraft missions. In this work, we present our recent experiences with the use of UAVs for hydrologic assessments and modeling at the Jornada Experimental Range in Las Cruces, New Mexico. We document the capability of UAV platforms for obtaining very high resolution imagery, digital elevation models and vegetation canopy properties over an experimental watershed equipped with a distributed sensor network of water, energy and carbon states and fluxes. We also draw attention to the important interaction between UAV products and their direct use in hydrologic models at the watershed scale. From a hydrologic perspective, the development of UAV techniques should be driven by the necessary inputs to a hydrologic model or the potential for utilizing the imagery to test the model predictions. This co-development can ensure that remote sensing advances make their way into products that directly quantify the hydrologic cycle and improve predictive skill at a range of resolutions. We present results from the application of the Triangulated Irregular Network (TIN)-based Real-time Integrated Basin Simulator (tRIBS) to the instrumented upland watershed to highlight the challenges and benefits of these tailored remote sensing products. We also discuss how UAVs could be used to validate upcoming products from satellite missions for the purpose of improving their routine use in a range of watershed models applied at local to regional scales.}, author = {A. Rango and Enrique Vivoni} } @conference {JRN54459, title = {Hierarchical spatial processes in grassland-shrubland transitions in the Southwestern US}, booktitle = {63rd Society for Range Management Annual Meetings}, year = {2010}, month = {02/2010}, publisher = {Sociiety for Range Management}, organization = {Sociiety for Range Management}, address = {Denver, CO}, abstract = {

Grassland to shrubland transitions have been widely reported in drylands across the world, but remain poorly understood beyond local-scale drivers. Knowledge of ecosystem spatial properties and the environmental constraints underlying landscape pattern is crucial to determining why shrublands have replaced grasslands in some areas and not others as well as predicting where such transitions may be most likely to occur in the future. Managers need to anticipate which landscapes are most susceptible to shrub encroachment. Information currently available from traditional point-based inventory and monitoring programs and small-scale or short-term field experiments is not sufficient to make these predictions. We describe how a landscape perspective that acknowledges the role of heterogeneity in land history, soil-geomorphic patterns and processes, and other broad-scale interactions can be used to interpret and predict local state-transitions. Specifically, we use historical aerial photography, high resolution satellite data, land-use maps, soil maps, and soil-vegetation inventory to produce a spatial state-and-transition model for a relict basin floor landscape in south-central New Mexico. We illustrate how variation in soil development, land-use decisions in the early 20th century, and contagious processes related to shrub spread and erosion that have shaped the pattern of transition in this landscape. We also note the implications of these patterns for management responses at different points in time and in different parts of the landscape.\  Abstract $\#$ PC-94.

}, author = {D. Goolsby and Brandon T Bestelmeyer and Steven R. Archer} } @article {50044, title = {Hierarchical object-based classification of ultra-high-resolution digital mapping camera (DMC) imagery for rangeland monitoring and assessment}, journal = {Journal of Spatial Science}, volume = {55}, year = {2010}, month = {June 2010}, pages = {101-115}, chapter = {101}, abstract = {Ultra high resolution digital aerial photography has great potential to complement or replace ground measurements of vegetation cover for rangeland monitoring and assessment. We investigated object-based image analysis (OBIA) techniques for classifying vegetation in southwestern U.S. arid rangelands with 4 cm resolution digital aerial photography. We obtained high r-square values for image- and ground-based measures of percent cover (r-square values: 0.82-0.92). OBIA enabled us to automate the classification process and demonstrated potential for quantifying fine-scale land cover attributes with ultra high resolution imagery. This approach exhibits promise for nationwide application for monitoring grazing lands.}, keywords = {aerial photography, object-based image analysis, rangelands, vegetation classifications, very high resolution}, doi = {10.1080/14498596.2010.487853}, url = {/files/bibliography/10-023.pdf}, author = {Andrea S. Laliberte and Dawn M. Browning and Jeffrey E. Herrick and Peg Gronemeyer} } @inbook {50065, title = {Herbivore-plant interactions and desertification in arid lands}, booktitle = {All Flesh is Grass}, series = {Cellular Origin, Life in Extreme Habitats and Astrobiology}, number = {16}, year = {2010}, pages = {239-256}, publisher = {Springer-Verlas}, organization = {Springer-Verlas}, abstract = {Arid lands around the world have experienced or are currently experiencing degradation that is known as desertification. Animal-plant interactions that have an effect on desertification are among the most important function of animals in arid ecosystems. Desertification has been defined as land degradation in arid and semiarid areas that is the result of various factors, including climate variation and human activities. The interactions between animals and plants affect desertification arid environments in a number of ways. These interactions may exacerbate desertification processes or contribute to the stability of desertified ecosystems. Some animal-plant interactions are direct, e.g., herbivory, while others are indirect, e.g., seed dispersal and soil modification. Animal-plant interactions that contribute to changes in the structure of plant communities or the spread of alien plant species may enhance some degradation processes such as soil erosion or contribute to soil stability and resistance to degradation.}, keywords = {herbivory, plant-animal interactions}, url = {/files/bibliography/10-037.pdf}, author = {Walter G. Whitford and Yosef Steinberger} } @conference {50138, title = {Habitat use by Mexican criollo and British beef cattle breeds in arid-and semi-arid environments of New Mexico and Chihuahua}, booktitle = {94th Annual Ecological Society of America Meeting}, year = {2009}, note = {Abstract $\#$ 19351}, month = {08/2009}, pages = {COS 15-9}, address = {Alb., NM}, abstract = {

Livestock grazing is the primary activity on rangelands that encompass nearly half of the Earth\’s terrestrial surface and directly supports a quarter of the world\’s population. With one person in ten directly involved livestock production, development of ecologically appropriate techniques for managing livestock grazing are likely to have widespread impacts. In this study we test the hypothesis that ecologically adapted Mexican Criollo cattle use a greater diversity of arid and semi-arid landscape components than temperate British beef cattle breeds (Angus, Hereford). Two sites were used: the Jornada Experimental Range (JER) in south-central New Mexico and Rancho Experimental Teseachi (RET) in central Chihuahua. The JER pasture has 1,160 ha of undulating Chihuahuan Desert grasslands, with 245 mm of average annual precipitation. Elevation of the 2,552 ha RET pasture varies from 1,900 to 2,800 m, with annual precipitation averaging 580 mm. Vegetation ranges from Pinyon-Juniper-Bouteloua on the lower slopes to Pine-Oak-Muhlenbergia on the upper slopes. Four replicates were used during the spring and fall at each location. In each replicate, six different mature cows per breed were fitted with Lotek GPS collars, equipped with activity sensors, and allowed to graze each pasture with position acquired at 5-min intervals. Results/Conclusions In contrast to British breeds, criollo cattle grazed fewer hours per day (9.82 vs 10.6 h/d; P \< 0.0001) and walked greater distances (8.0 vs 6.8 km/d; P \< 0.0001). In addition, British breeds remained closer (P \< 0.05) to water and maintained smaller (P \< 0.05) home ranges when forage availability and quality tended to be limiting. Overall British breeds grazed more and used a smaller proportion of the environment than Mexican criollo cattle. This study was conducted when forage conditions at both sites were better than typically encountered; under poorer forage conditions, common to northern Mexico and southwestern United States, differences between breeds could be greater than observed. These data indicate that desert adapted criollo cattle, evolving in arid- and semi-arid regions of Spain and North Africa before their introduction to Mexico in 1521, distribute their impacts more evenly across fragile landscapes. This is likely due to their smaller size, though other arid land adaptations are likely. Use of desert adapted cattle appears to be a mechanism to lessen localized overgrazing common to these systems when using larger temperate breeds, and may be an appropriate breed for areas with sensitive riparian communities.

}, keywords = {Chihuahua, ESA, grazing, livestock, production}, author = {Roacho, E.J.O. and E.L. Fredrickson and G. Bezanilla and Amy L. Gonzalez and H. Raul Peinetti and A.F.A. Rodriguez} } @article {50139, title = {Historical and modern distrubance regimes, strand structures, and landscape dynamics in pinon-juniper vegetation of the western United States}, journal = {Rangeland Ecology and Management}, volume = {62}, year = {2009}, month = {03/2009}, pages = {203-222}, chapter = {203}, abstract = {

Pi{\~n}on{\textendash}juniper is a major vegetation type in western North America. Effective management of these ecosystems has been hindered by inadequate understanding of 1) the variability in ecosystem structure and ecological processes that exists among the diverse combinations of pi{\~n}ons, junipers, and associated shrubs, herbs, and soil organisms; 2) the prehistoric and historic disturbance regimes; and 3) the mechanisms driving changes in vegetation structure and composition during the past 150 yr. This article summarizes what we know (and don{\textquoteright}t know) about three fundamentally different kinds of pi{\~n}on{\textendash}juniper vegetation. Persistent woodlands are found where local soils, climate, and disturbance regimes are favorable for pi{\~n}on, juniper, or a mix of both; fires have always been infrequent in these woodlands. Pi{\~n}on{\textendash}juniper savannas are found where local soils and climate are suitable for both trees and grasses; it is logical that low-severity fires may have maintained low tree densities before disruption of fire regimes following Euro-American settlement, but information is insufficient to support any confident statements about historical disturbance regimes in these savannas. Wooded shrublands are found where local soils and climate support a shrub community, but trees can increase during moist climatic conditions and periods without disturbance and decrease during droughts and following disturbance. Dramatic increases in tree density have occurred in portions of all three types of pi{\~n}on{\textendash}juniper vegetation, although equally dramatic mortality events have also occurred in some areas. The potential mechanisms driving increases in tree density{\textemdash}such as recovery from past disturbance, natural range expansion, livestock grazing, fire exclusion, climatic variability, and CO2 fertilization{\textemdash}generally have not received enough empirical or experimental investigation to predict which is most important in any given location. The intent of this synthesis is 1) to provide a source of information for managers and policy makers; and 2) to stimulate researchers to address the most important unanswered questions.La vegetaci{\'o}n de Pi{\~n}on-jun{\'\i}pero es un tipo de vegetaci{\'o}n muy importante en el Oeste de Norte Am{\'e}rica. El manejo efectivo de estos ecosistemas se ha obstaculizado por el inadecuado entendimiento de 1) la variabilidad en la estructura del ecosistema y los procesos ecol{\'o}gicos que existen entre las diversas combinaciones de pinos, jun{\'\i}peros, arbustos, hierbas, y los organismos asociados del suelo; 2) reg{\'\i}menes prehist{\'o}ricos e hist{\'o}ricos del disturbio, y 3) mecanismos que conducen cambios en estructura y composici{\'o}n de la vegetaci{\'o}n durante los {\'u}ltimos 150 a{\~n}os. Este publicaci{\'o}n hace un resumen de lo que sabemos (y no sabemos) acerca de tres clases fundamentales de vegetaci{\'o}n del pi{\~n}on{\textendash}junipero. Arbolados persistentes se encuentran donde los suelos locales, el clima, y los reg{\'\i}menes del disturbio son favorables para el pi{\~n}{\'o}n, el jun{\'\i}pero, o una mezcla de ambos; los fuegos han sido siempre infrecuentes en estas {\'a}reas. Las sabanas del Pi{\~n}on{\textendash}junipero se encuentran donde los suelos locales y el clima son apropiados tanto para {\'a}rboles y gram{\'\i}neas; es l{\'o}gico que los fuegos de baja-intensidad pueden haber mantenido densidades bajas de {\'a}rboles antes de que se interrumpi{\'o} los reg{\'\i}menes del fuego despu{\'e}s del establecimiento Euro-Americano, pero existe poca informaci{\'o}n para apoyar cualquier afirmaci{\'o}n afirmativa sobre los reg{\'\i}menes hist{\'o}ricos del disturbio en estas sabanas. Los matorrales se localizan donde los suelos locales y el clima apoyan a comunidad de arbustos, pero los {\'a}rboles pueden aumentar durante condiciones clim{\'a}ticas y per{\'\i}odos h{\'u}medos sin disturbio, y disminuyen durante sequ{\'\i}as y despu{\'e}s del disturbio. Los aumentos dram{\'a}ticos en la densidad de los {\'a}rboles han ocurrido en las porciones de los tres tipos de vegetaci{\'o}n del pi{\~n}on{\textendash}junipero, aunque eventos igualmente dram{\'a}ticos de mortalidad han ocurrido tambi{\'e}n en algunas {\'a}reas. Los mecanismos potenciales que conducen aumentos en densidad de {\'a}rboles, la recuperaci{\'o}n del {\'u}ltimo disturbio, la extensi{\'o}n natural del pastizal, el pastoreo del ganado, la exclusi{\'o}n del fuego, la variabilidad clim{\'a}tica, y la fertilizaci{\'o}n-general del CO2 no han recibido suficiente investigaci{\'o}n emp{\'\i}rica o experimental para predecir cu{\'a}l de estos factores puede ser el m{\'a}s importante en cualquiera de los sitios. El intento de esta s{\'\i}ntesis es 1) proporcionar una fuente de informaci{\'o}n para los manejadores y los regidores, y 2) estimular a investigadores para dirigir las preguntas m{\'a}s importantes que aun est{\'a}n sin contestar.

}, keywords = {climate, CO2, drought, fire, grazing, range expansion, tree infill, tree invasion}, url = {/files/bibliography/09-014.pdf}, author = {W.H. Romme and C.D. Allen and J.D. Bailey and W.L. Baker and Brandon T Bestelmeyer and P.M. Brown and K.S. Eisenhart and Floyd-Hanna, L. and D.W. Huffman and Jacobs, B. F. and Richard F. Miller and E. Muldavin and Swetnam, T.W. and R. J. Tausch and Weidberg, P.J.} } @conference {50148, title = {How to document soil change without monitoring: A multi-scale inventory procedure for dynamic soil properties, soil change, and plant community dynamics}, booktitle = {62nd Society for Range Mangement Annual Meeting}, year = {2009}, month = {02/2009}, pages = {2060-18}, publisher = {Society for Range Management}, organization = {Society for Range Management}, address = {Alb., NM}, abstract = {

The National Cooperative Soil Survey is now following data collection procedures to characterize dynamic soil properties. The new procedures use simple conceptual models of management effects on soil (such as state and transition models) to stratify the soil map unit for a comparison study. Once stratified, both soil and vegetation (where present) data are collected. Replicate sampling is conducted at multiple scales. A cooperative effort to develop sampling guidelines was initiated in 2004. NRCS, working with the Agricultural Research Service Jornada Experimental Range, National Park Service, Forest Service, and Bureau of Land Management developed the \“Soil Survey and Resource Inventory Guide for Dynamic Soil Properties and Soil Change\”. Data collection will be organized within projects to document land use or management effects on benchmark soils and ecological sites. Soils selected for sampling should be extensive and ecologically or economically important, or represent unique ecological zones. Comparison study projects, which are designed to characterize dynamic soil properties for one or more land cover types, plant communities, or management systems, include the following six steps: 1) Project Scope, 2) Sampling Design, 3) Sampling Requirements, 4) Field Work, 5) Data Preparation, and 6) Data Analysis and Reports. These steps are described in this poster. Data and information about how soils change can be used by producers, land managers, and decision makers in order to plan for long-term productivity, interpret indicators used in monitoring and assessments, and manage human impacts on soil.

}, keywords = {abstract, data collection, National Cooperative Soil, SRM, state and transition}, author = {A.J. Tugel and S.A. Wills and Jeffrey E. Herrick and Biggam, P.} } @article {50153, title = {Harvester ants (Hymenoptera: Formicidae) discriminate among artificial seeds with different protein contents}, journal = {Sociobiology}, volume = {53}, number = {2B}, year = {2009}, month = {03/2009}, pages = {549-558}, chapter = {549}, abstract = {

Workers of colonies of the western harvester ant, Pogonomyrmex occidentalis, were recruited to patches of artificial seed of the same caloric value but different protein content. Rates of forager returns with artificial seeds containing five percent protein were nearly twice those of zero percent protein. Differences in foraging rates on artificial seeds of ten and twenty percent protein compared to foraging rates on zero percent protein seeds were not different from the comparison of foraging rates on five percent and zero percent protein seeds. There were no differences in foraging rates on zero percent protein seeds, 0.5 percent and one percent protein seeds. P. occidentalis presented with patches containing equal amounts of zero, five, ten, and twenty percent protein seeds returned equal amounts of each protein content seed type to the colonies. When presented with high quality seed patches in the same location for four successive days, the rates of forager returns increased over time. When seed patch locations were switched, P. occidentalis\&$\#$39; rate of return of zero protein content seeds was the same as for the five percent protein seeds at that location the previous day. Seeds with protein content between one and two percent represent a threshold for seed quality that affects the foraging rate of P. occidentalis workers.

}, keywords = {food choices, Harvester ants, journal, Pogonomyrmex occidentalis, protein}, url = {/files/bibliography/09-009.pdf}, author = {Walter G. Whitford and Yosef Steinberger} } @proceedings {50157, title = {Husbandry of free-ranging cows using virtual fencing concepts}, volume = {1}, year = {2008}, month = {June 30 - July 5}, pages = {660}, publisher = {Guangdong People{\textquoteright}s Publishing House}, address = {Hohhot, China}, abstract = {A directional virtual fencing (DVF{\texttrademark}) system approach employing 1 Hz GPS data acquisition and using audio cuing only was successfully used to gather mature free-ranging beef cattle from a 466 ha arid brush infested rangeland paddock into a corral in which drinking water was located . Gathering was conducted during five random morning and five random afternoon times over a two week period not corresponding to when the cattle would normally enter the corral. Their normal time to enter the corral was determined by a one week pre-trial for each group during which time the animal{\textquoteright}s normal time to enter the corral was recorded. The audio cues consisted of a human voice and those sounds coming from an all-terain vehicle (ATV) that had previousl been recorded during one of the manual gathering/training sessions. The treated cattle had previously been habituated to being gathered by a technician riding an ATV and once the cows arrived at the corral they were given a small amont of protein supplement and immediate access to drinking water. In contrast, a similar group of cattle not accustomed to being gathered using this protocol but trained to wear the electronic equipment package as well as eat protein supplement were subjected to autonomous gathering. This study demonstrated the feasability of using electronic equipment together with a food reward in order to autonomously gather free-ranging cows.}, keywords = {free-ranging, GPS, virtual fencing}, author = {D.M. Anderson} } @article {50205, title = {Habitat selection by a rare forest antelope: A multi-scale approach combining field data and imagery from three sensors}, journal = {Remote Sensing of Environment}, volume = {112}, year = {2008}, pages = {2033-2050}, keywords = {Akaike{\textquoteright}s Information Criterion, ASTER, field data, forest structure, habitat selection, herbivore, logistic regression, MODIS, mountain bongo, rare species, scale, spectral mixture analysis, SPOT, texture analysis, topographic correction}, doi = {doi:10.1016/j.rse.2008.01.004}, author = {L. D. Estes and Gregory S. Okin and A. G. Mwangi and Shugart, H. H.} } @article {50206, title = {Higher effect of plant species diversity on productivity in natural than artificial ecosystems}, journal = {Proceedings of the National Academy of Sciences}, volume = {105}, year = {2008}, note = {//OTHER//OTHER//entered 06/02/2008 per DEP}, month = {2008}, pages = {6087-6090}, keywords = {article, biodiversity, plant, carbon cycle, ecosystem, artificial, ecosystem, natural, journal, Patagonian steppe, resource partitioning}, author = {P. Flombaum and O. E. Sala} } @inbook {50244, title = {Human health, biodiversity and ecosystem services: the intertwined challenging future}, booktitle = {Biodiversity change and human health: from ecosystem services to spread of disease}, year = {2008}, note = {//OTHER//LTER-V//entered 06/02/2008 per DEPProCite field[6]: In}, month = {2008}, publisher = {Island Press}, organization = {Island Press}, address = {Washington, DC}, abstract = {

In a world where scarcity of food, water, and fuel is an immediate challenge and not just a future specter, the maintenance of\  biodiversity and ecosystem services is critical to human health and welfare. Th e climate change wild card adds insecurity as to what biotic resources and tools may be needed for human adaptation to food supply disruptions, ecosystem alterations, shift ing disease patterns, and other health threats. Th ere is great uncertainty about the future interaction between human health and changes in biodiversity. In many ways, we are collectively experimenting blindly with the ecology of the entire planet. However, we know enough to describe several major challenges and important research needs.

}, keywords = {biodiversity, book, chapter, disease, ecosystem services, human health, report}, url = {files/bibliography/JRN00502.pdf}, author = {Meyerson, F. A. B.. and Meyerson, L. A. and C. Parmesan and O. E. Sala}, editor = {O. E. Sala and Meyerson, L. A. and C. Parmesan} } @article {50270, title = {Hyperhydricity reversal and clonal propagation of fourwing saltbush (Atriplex canescens, Chenopodiaceae) cultivated in vitro}, journal = {Australian Journal of Botany}, volume = {56}, number = {4}, year = {2008}, month = {July 2008}, pages = {358-362}, publisher = {CSIRO Publishing}, abstract = {

In vitro propagated shoots of fourwing saltbush [Atriplex canescens (Pursh Nutt)] showed severe symptoms of hyperhydricity. Hyperhydricity is a frequent physiological problem reported in micropropagation of A. canescens and other plant species, and drastically reduces the quality of in vitro cultures. It is exacerbated when plants are cultured in airtight culture vessels on medium formulations with high nitrogen concentrations. We show that the reversion of hyperhydric A. canescens shoots to normal shoots was significantly affected by the presence of inorganic nitrogen in the culture vessel. When the culture vessel was vented or when ammonium nitrate was deleted from Murashige and Skoog basal medium, rates of reversion were significantly higher. While statistically significant differences were evident when comparing vented vs. non-vented treatments for each medium, the modified culture medium with vented closures was consistently the best treatment, showing a total cumulative frequency of 39.7\% compared with a total cumulative frequency of 7.1 \% observed in the control treatment. Resulting normal shoots also showed significant improvements in further manipulations, including rooting in vitro, transplantation to soil, and survival in native sites.

}, keywords = {botany, clonal, fourwing, hyperhydricity, saltbush}, doi = {10.1071/BT07116}, url = {/files/bibliography/08-024.pdf}, author = {I. Reyes-Vera and Potenza, C.L. and J.R. Barrow} } @article {50277, title = {Historical and modern disturbances regimes, stand structures, and landscape dynamics in pinon-juniper vegetation of the western U.S.}, year = {2008}, month = {June 4, 2008}, pages = {35 p}, abstract = {Pi{\~n}on-juniper is one of the major vegetation types in western North America. It covers a huge area, provides many resources and ecosystem services, and is of great management concern. Management of pi{\~n}on-juniper vegetation has been hindered in the past by inadequate understanding of its prehistoric and historic dynamics, of the mechanisms controlling those dynamics, and of the variability in ecosystem structure and process that exists among the many different environmental contexts and floristic combinations of pi{\~n}on, juniper and associated species. This paper presents a summary of what we currently know {\textendash} and don{\textquoteright}t know {\textendash} about historical and modern stand and landscape structure and dynamics, in three major and fundamentally different kinds of pi{\~n}on-juniper vegetation in the western U.S.: persistent woodlands, savannas, and wooded shrublands. It is the product of a workshop that brought together experts from across the geographical range of pi{\~n}on-juniper vegetation. The intent of this synthesis is to provide a source of information for managers and policy-makers, and to stimulate researchers to address the most important unanswered questions.}, keywords = {ecosystem, management, North America, pinon-juniper, vegetation}, url = {/files/bibliography/08-026.pdf}, author = {W.H. Romme and C.D. Allen and J.D. Bailey and W.L. Baker and Brandon T Bestelmeyer and P.M. Brown and K.S. Eisenhart and Floyd-Hanna, L. and D.W. Huffman} } @proceedings {50294, title = {How Does targeted grazing with small ruminants influence subsequent patch use by mule deer and cattle?}, year = {2008}, month = {July 18, 2008}, pages = {21-22}, address = {Corona, NM}, abstract = {Small ruminants are increasingly being used in controlled grazing programs to target undesirable vegetation. It has not been determined how targeted juniper browsing affects subsequent use of those patches by cattle and wildlife. To determine whether cattle or mule deer used or avoided patches that had been intensively browsed by sheep and goats, presence of deer and cattle on patches of juniper infested rangeland that had previously been subjected to four targeted grazing prescriptions were monitored. Digital cameras with infrared motion sensors were installed in 10 plots and maintained for one year after intensive grazing by small ruminants. Four single large patches (20 x 30 m) and four patches containing six small (10 x 10 m) plots subjected previously to browsing by goats or goats plus sheep at high (10 m2/AU/day) or low (60 m2/AU/day) stocking density were used (two replicates per treatment), and two other large plots without previous intensive targeted grazing served as controls. Selection indices (frequency of animals in plots compared to control plots) were determined. Both deer and cattle avoided large patches that had been previously browsed by sheep and goats. These patches had received heaviest use of herbaceous vegetation the previous summer (> 73\%). Deer selected small patches that had previously been browsed by sheep and goats (SI: 2.24), whereas cattle selected large patches (SI: 1.50) and avoided small patches (SI: 0.59) that had been browsed by goats alone. Cattle showed greatest preference for grazed patches during summer (SI: 3.18), while deer avoided them during summer (SI: 0.20) and spring (SI: 0.13). Presence of cattle on a given patch reduced the probability of mule deer presence.}, keywords = {cattle, Corona, mule deer, proceedings, small ruminants}, url = {/files/bibliography/08-036.pdf}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and Boren, J. and Brad Cooper and S.H. Cox and D. VanLeeuwen} } @article {50325, title = {The high water-holding capacity of petrocalcic horizons}, journal = {Soil Science Society of America}, volume = {71}, number = {3}, year = {2007}, month = {05/2007}, pages = {812-819}, abstract = {

Petrocalcic soil horizons occur in most arid and semi-arid ecosystems around the world, often within the plant rooting zone. Little is known, however, about the water holding characteristic of soils indurated with calcium carbonate. We conducted a replicated experiment to define the soil-water release curve (SWRC) for a range of petrocalcic horizon materials. Samples from both plugged and laminar zones of two stage V petrocalcic horizons in southern New Mexico were characterized. Wetter soil-water potentials were measured using a pressure plate; more negative potentials (down to \<{\textendash}10 MPa) were measured using a chilled mirror water activity meter. Measured SWRC data were fitted to the Van Genuchten equation. The SWRC methods used were found to be both reliable and repeatable. Plant available water holding capacity (AWHC) for desert species (with wilting point set at {\textendash}4.0 MPa)ranged from 0.26 m3 m-3 in plugged zones to 0.06 m3 m-3 in some laminar zones in contrast to ~ 0.07 m3 m-3 in the loamy sand parent material. Correlation analyses across morphologies of AWHC and soil properties resulted in significant statistical relationships only with bulk density and porosity. AWHC and calcium carbonate content, however, were significantly negatively correlated within the laminar and positively correlated within the plugged petrocalcic horizon morphologies. Cementation by calcium carbonate dramatically alters the water holding characteristics of soils and understanding these horizons is crucial to understand patterns of soil-water in desert systems throughout the world.

}, keywords = {Petrocalcic, soil}, url = {/files/bibliography/07-014.pdf}, author = {Danielle Duni and Jeffrey E. Herrick and Curtis H. Monger} } @inbook {50420, title = {A Holistic View of an Arid Ecosystem: A Synthesis of Research and Its Applications}, booktitle = {Structure and Function of a Chihuahuan Desert Ecosystem: The Jornada Basin Long-Term Ecological Research Site}, year = {2006}, month = {July 1, 2006}, pages = {354-368}, publisher = {Oxford University Press}, organization = {Oxford University Press}, chapter = {17}, address = {New York}, abstract = {A primary objective of the Jornada Long-Term Ecological Research (LTER) program has been to provide a broad view of desert grassland ecology. Early architects of the LTER program felt that existing ecological datasets were usually of too short a duration and represented too few ecosystem components to provide a foundation for predicting dynamics in response to disturbances (NSF 1979). This recognition gave rise to the LTER approach{\textemdash}using long-term and multidisciplinary research at particular places to advance a holistic and broad-scale, but also mechanistic, view of ecological dynamics. Such a view is essential to applying ecological research to natural resources management (Golley 1993; Li 2000). In this synthesis chapter we ask: What has this approach taught us about the structure and function of a desert grassland ecosystem? How should this knowledge change the way we manage arid ecosystems? What gaps in our knowledge still exist and why?}, keywords = {Chihuahuan Desert, desert grassland ecosystem, holistic view, Jornada Basin, LTER, multidisciplinary, patch-based correlations, research, synthesis book}, url = {/files/bibliography/06-068.pdf}, author = {Brandon T Bestelmeyer and Joel R. Brown and Kris Havstad and E.L. Fredrickson}, editor = {Kris Havstad and L. Huenneke and W. H. Schlesinger} } @conference {50421, title = {How can LTER data contribute to ecosystem management}, booktitle = {LTER All Scientists Meeting}, year = {2006}, month = {September 21, 20}, pages = {Paper No. 35}, address = {Estes Park, CO}, abstract = {Research conducted at LTER sites has great potential for use by natural resource managers and policymakers within the surrounding regions, but in many cases the link between LTER data and management policy is limited. We use examples from the Jornada Basin LTER to illustrate some general steps and research questions that can connect LTER research to whole-ecosystem management (e.g., the Bureau of Land Management, Forest Service, ranchers). The steps/questions include 1) what are spatial extents, often defined by climate and physiography, within which ecological patterns and processes are similar, 2) what are the key gradients and thresholds in soil and climate within regions governing ecological processes, 3) what is the distribution of potential and alternative ecosystem states along the gradients, 4) what are the mechanisms of transition among states, 5) what patterns and tools can be used to recognize and map states within the region, and 6) how should recognition of states be used to generate management decisions?}, keywords = {ecosystem, LTER, management}, author = {Brandon T Bestelmeyer and Caitriana Steele and Jeffrey E. Herrick and Curtis H. Monger} } @article {50435, title = {Habitat loss, trophic collapse, and the decline of ecosystem services}, journal = {Ecology}, volume = {87}, number = {8}, year = {2006}, note = {//Other//LTER-V//entered 08/15/2007}, month = {2006}, pages = {1915-1924}, abstract = {

The provisioning of sustaining goods and services that we obtain from natural ecosystems is a strong economic justification for the conservation of biological diversity. Understanding the relationship between these goods and services and changes in the size, arrangement, and quality of natural habitats is a fundamental challenge of natural resource management. In this paper, we describe a new approach to assessing the implications of habitat loss for loss of ecosystem services by examining how the provision of different ecosystem services is dominated by species from different trophic levels. We then develop a mathematical model that illustrates how declines in habitat quality and quantity lead to sequential losses of trophic diversity. The model suggests that declines in the provisioning of services will initially be slow but will then accelerate as species from higher trophic levels are lost at faster rates. Comparison of these patterns with empirical examples of ecosystem collapse (and assembly) suggest similar patterns occur in natural systems impacted by anthropogenic change. In general, ecosystem goods and services provided by species in the upper trophic levels will be lost before those provided by species lower in the food chain. The decrease in terrestrial food chain length predicted by the model parallels that observed in the oceans following overexploitation. The large area requirements of higher trophic levels make them as susceptible to extinction as they are in marine systems where they are systematically exploited. Whereas the traditional species{\textendash}area curve suggests that 50\% of species are driven extinct by an order-of-magnitude decline in habitat abundance, this magnitude of loss may represent the loss of an entire trophic level and all the ecosystem services performed by the species on this trophic level.

}, keywords = {article, biodiversity, conservation, ecosystem function, ecosystem services, food web, journal, Little Rock Lake, species loss, species-area, trophic collapse}, doi = {10.1890/0012-9658(2006)87[1915:HLTCAT]2.0.CO;2}, url = {files/bibliography/JRN00444.pdf}, author = {Dobson, Andrew and Lodge, David and Alder, Jackie and Cumming, Graeme S. and Keymer, Juan and McGlade, Jacquie and Mooney, Hal and Rusak, James A. and O. E. Sala and Wolters, Volkmar and D.H. Wall and Winfree, Rachel and Xenopoulos, Marguerite A.} } @proceedings {50532, title = {Hybrid vigor, structural modification, and enhanced plant performance induced by symbiotic fungi-plant interactions}, year = {2005}, month = {July 30-August 5}, address = {Hilo, Hawaii}, abstract = {Communities of symbiotic fungi are intrinsically integrated with single cells, tissues, and organs of desert plants. They are obligately associated with living tissues and generally cannot be isolated and cultured separately. Symbiotic fungi indigenous to native desert plants were transferred, using cell culture methods, to nonhost plants and reciprocally transferred between native grasses. Crop and native plants with recipient fungi have astounding and increased levels of vigor. Up to fivefold increases in root and shoot biomass and substantial morphological changes and reproductive potential were obtained. Enhanced chlorophyl and phosphorous content were common responses. Once integrated, fungi were intimately interfaced with the plasmalema of the new host plant and were ecto-cytoplasmically inherited. This technology accesses a previously unexplored source of genetic variability within native ecosystems with the potential of immediate transfer to improve tolerance of native and crop plants to stress, disease, and pests. Symbiotic fungal transfers provides a powerful alternative for genetic improvement of plants.}, keywords = {enhanced plant performance, hybrid vigor, structural modification, symbiotic fung-plant interactions}, author = {J.R. Barrow and M.E. Lucero and P. Osuna-Avila and I. Reyes-Vera and Aaltonen, R.E.} } @article {50568, title = {Historical analysis of the irrigation evolution of the Laguna region of Mexico}, journal = {Terra Latinoamericana}, volume = {23}, number = {3}, year = {2005}, note = {//NONE//LTER IV//added 07/29/2005; updated 04/17/2008; PDF on file}, month = {2005}, pages = {363-370}, abstract = {

The people of La Laguna Region of Mexico are highly dependent on the irrigated agriculture of the region. The magnitude of irrigation has increased in recent times to the point that water tables are lowering and that soil properties are actually being affected. The main objective of this paper was to analyze the evolution of irrigation in La Laguna Region and locate the irrigation areas throughout time in order to be a reference for future research about soil property changes with the irrigation practice in the region. Old books, maps, articles, personal interviews, historic museums and libraries of La Laguna Region, and records of Mexican government institutions were investigated. Also, a geographic information system was used to locate the irrigation areas throughout time from old maps. The history analysis of the region reveals that there were four periods important to the evolution of irrigated agriculture: The big Latifundios Period (1700 to 1825) when the entire Laguna Region was used for grazing and livestock activities: the Hacienda Period (1840 to 1910) when irrigation began, grew and boomed together with cotton; the Period after the Agrarian act (1936 to 1946) when the farmers used the old and deficient irrigation infrastructure; and finally the Modernization Period (1950 to 1975) when important hydraulic structures were made for improving the irrigation system of today.

}, keywords = {agriculture, irrigated, article, GIS, history, agriculture, history, hacienda period, history, irrigation, history, latifundio period, history, livestock period, history, modernization period, history, prehistoric period, irrigation, history, irrigation, practices, irrigation, water table, journal, La Laguna Region, Mexico}, url = {files/bibliography/JRN00427.pdf}, author = {Inzunza-Ibarra, Marco A. and Curtis H. Monger} } @conference {50647, title = {The high water-holding capacity of petrocalcic horizons}, booktitle = {Soil Science Society of America Annual Meeting}, year = {2004}, month = {October 31-Novem}, address = {Seattle, WA}, abstract = {Petrocalcic soil horizons develop extensively in arid ecosystems around the world, often within the rooting zone of many desert plant species. In coarse textured soils, this results in a dramatic change in moisture holding capacity through the conversion of a horizon dominated by large pores to a fine pore matrix. We conducted a replicated experiment to measure the characteristic moisture release curve for a range of petrocalcic horizon materials. Samples from both the plugged and laminar horizons from two stage V petrocalcic horizons in southern New Mexico were sampled. Tensions closer to zero were measured using a pressure plate; more negative tensions (down to {\textendash}5Mpa) were measured using a chilled mirror water potential device (Decagon Devices WP4). Our method was repeatable and results were fitted using the vanGenuchten equation. Plant available volumetric water holding capacity for desert species (with permanent wilting point set at {\textendash}4Mpa) ranged from 24\% in plugged horizons to 3\% in some laminar horizons in contrast to approximately 5.5\% in a loamy sand. Cementation by calcium carbonate dramatically alters the water-holding characteristics of soils and understanding these horizons is crucial for understanding patterns of soil water in desert systems.}, keywords = {arid, ecosystems, horizons, Petrocalcic, soil, soil water, water-holding capacity}, author = {Danielle Duni and Jeffrey E. Herrick and Curtis H. Monger and Brinegar, H.R.} } @conference {50680, title = {Human influences on range contractions of North American carnivores and ungulates}, booktitle = {Carnivores 2004 Conference: Defenders of Wildlife}, year = {2004}, month = {November 15, 200}, pages = {132}, address = {Santa Fe, NM}, abstract = {Knowledge of the geographical distribution of species is important for conservation biology. However, few studies have examined the dynamics of species ranges and changes over time and space. In addition, we know very little about human influences on species range changes at the continental scale. We compared the historic and current geographical ranges of 43 North American carnivores and ungulates to identify large-scale patterns in range contractions and expansions. Our objectives were to determine the degree of human influence on species range changes, to describe range changes with regard to biomes and elevation, and to describe changes in species richness. Seventeen of the species had experienced range contractions over more than 20\% of their historic range. Electivity indices showed a strong correlation between human influence and species range contractions. In areas of higher human influence, species were more likely to contract and less likely to persist. Species richness had also declined considerably since historic times. The temperate grasslands and temperate broadleaf{\textquoteright}mixed forest biomes lost the highest average number of species, while the boreal forest and tundra showed fewer numbers of species lost. Our spatial quantification at the continental scale showed that species contractions have been widespread, crossing regional and country boundaries and that this rapid collapse occurred over the course of only one to two centuries. The results of this study can be used to improve scientists{\textquoteright} knowledge of historical reference conditions and to provide input for wildlife reintroductions and for the creation of wildlife reserves.}, keywords = {biomes, carnivores, elevation, human influences, North America, range contractions, species range changes, ungulates}, author = {Andrea S. Laliberte and Ripple, W.J.} } @conference {50756, title = {Hydrologic input, nutrient and pollutant budgets, and biotic components of the North Caspian Sea}, booktitle = {17th Biennial Meeting of the Estuarine Research Federation}, year = {2003}, month = {September 2003}, address = {Seattle, WA}, abstract = {The North Basin of the Caspian Sea is predominantly a shallow water estuary of the Volga River. The Volga River provides approximately 80\% of the total riverine water input to the entire Caspian and represents the largest source of nutrients (N, P, and Si etc.) and pollutants (hydrocarbons, pesticides etc.). The Ural River also contributes inputs but on a much smaller scale, representing less than 5\% of the riverine input to the Caspian Sea. In order to understand the ecological functioning and current status of the North Caspian, we will present hydrologic, carbon, organic and inorganic nutrient, and pollutant budgets impacting this rich estuarine system, as well as estimates of biomass and productivity of major components of the food web. These include phytoplankton, zooplankton and zoobenthic communities, invading species such as the comb jelly Mnemiopsis leidyi, several species of fish which are important both ecologically and commercially, and the endemic Caspian Seal. Comparing data collected during the Soviet era to more recent analyses, it appears that the North Caspian is less polluted today. However, illegal fishing has endangered some economically important commercial fish stocks such as the Beluga sturgeon (Huso huso) and, to a lesser extent, other sturgeon species.}, author = {T.J. Butler and S. Tartowski and V. Bashkin and Lychagin, M.Y. and Sisengalieva, G. and Yergaliyev, T.} } @article {50769, title = {Historical shrub-grass transitions in the northern Chihuahan Desert: modeling the effects of shifting rainfall seasonality and event size over a landscape gradient}, journal = {Global Change Biology}, volume = {9}, year = {2003}, note = {//NMSU//LTER IV//entered 10/24/2005; entered 07/28/2008}, month = {2003}, pages = {1475-1493}, abstract = {

We use a spatially explicit landscape model to investigate the potential role of rainfall on shrub-grass transitions in the Jornada Basin of southern New Mexico during the past century. In long-term simulations (1915 - 1998) along a 2700m transect running from a dry lake bed to the foothills of a small mountain, we test two hypotheses: (i) that wetter winters and drier summers may have facilitated shrub encroachment in grasslands, and (ii) that increases in large precipitation events may have increased soil water recharge at deeper layers, thus favoring shrub establishment and growth. Our model simulations generally support the hypothesis that wetter winters and drier summers may have played a key role, but we are unable to reproduce the major shifts from grass- to shrubdomination that occurred in this landscape during the early part of the 1900s; furthermore, the positive shrub response to wetter winters and drier summers was only realized subsequent to the drought of 1951 - 1956, which was a relatively short {\textquoteleft}window of opportunity{\textquoteright} for increased shrub establishment and growth. Our simulations also generally support the hypothesis that an increase in the number of large precipitation events may also have favored shrub establishment and growth, although these results are equivocal, depending upon what constitutes a {\textquoteleft}large{\textquoteright} event and the timing of such events. We found complex interactions among (i) the amount/seasonality of rainfall, (ii) its redistribution in the landscape via run-on and runoff, (iii) the depth of the soil water recharge, and (iv) subsequent water availability for the growth and reproduction of shrubs vs. herbaceous plants at various landscape positions. Our results suggest that only a mechanistic understanding of these interactions, plus the role of domestic cattle grazing, will enable us to elucidate fully the relative importance of biotic vs. abiotic factors in vegetation dynamics in this semiarid landscape.

}, keywords = {article, climate, shrub-grass transition, grassland, model, grassland, shrub transition, journal, model, Bouteloua, model, desertification, model, grassland, model, hydrology, model, landscape, model, Larrea, model, Prosopis, model, rainfall, model, resource allocation, model, runoff, model, runon, model, shrub, model, shrub-grass, rainfall, model, shrub, grass transition, shrub, model}, doi = {10.1046/j.1365-2486.2003.00676.x}, url = {files/bibliography/JRN00386.pdf}, author = {Q. Gao and J. F. Reynolds} } @article {50772, title = {High-resolution images reveal rate and pattern of shrub encroachment over six decades in New Mexico, USA}, journal = {Journal of Arid Environments}, volume = {54}, number = {4}, year = {2003}, month = {August 1, 2003}, pages = {755-767}, abstract = {

Encroachment of the shrub Prosopis glandulosa (honey mesquite) into semiarid grasslands is a serious concern in the southwestern United States, yet little is known about the long-term dynamics of the invasion process. We used 10 high-resolution aerial and satellite images taken from 1936 to 1996 to track population dynamics and spatial pattern of all P. glandulosa greater than 2m in diameter on a 75-ha area in southern New Mexico. Shrub cover and patch numbers increased from 1936 to the 1970s, then stabilized at 43\% cover and 83 patches/ha. Individual patches were extremely persistent: 95\% of the area occupied by shrub patches in 1936 was still occupied in 1996. Recruitment into the 2m size class was more variable: 0.6 to 5.2\%/yr (mean 0.8\% yr). Patch shape complexity increased from 1936 to 1983 as adjacent shrubs merged and then declined as those clusters filled in and became rounder. Spatial pattern of shrubs showed a distinct trend over time: strongly clustered in 1936 at lag distances up to 250m, then random arrangement at all scales; and, by 1983 the pattern was regular at lag distances greater than 100m. There was no clear relationship with precipitation. The use of remote sensing imagery allowed us to examine one site over time and revealed patterns in population dynamics and spatial pattern that would not have been visible otherwise. Comparison of field estimates collected in 2001 with 1996 image data suggest the canopy cover estimates were accurate, but shrub densities were seriously underestimated in the satellite photographs which do not show shrubs smaller than 2m diameter. As long as limitations of the imagery are understood, these methods can be applied over a larger and more heterogeneous area to examine environmental correlates of invasion success.

}, url = {/files/bibliography/03-017.pdf}, author = {Sarah Goslee and Kris Havstad and Debra C. Peters and A. Rango and W. H. Schlesinger} } @proceedings {50807, title = {Historical and current hydrological research at the USDA-ARS Jornada Experimental Range in southern New Mexico}, volume = {1}, year = {2003}, note = {http://www.tucson.ars.ag.gov/unit/ICRW.htm; http://www.tucson.ars.ag.gov/icrw/Proceedings/Rango.pdf}, month = {October 27-30, 2}, pages = {302-308}, address = {Benson, AZ}, abstract = {The USDA-ARS Jornada Experimental Range (JER)(738 km2) north of Las Cruces, NM, was established in 1912 to assess the impact of grazing in an arid land environment. The majority of rainfall occurs during June-September with an annual mean of 241 mm. Ecophysiological studies employing stable isotopes are underway to identify the sources of water uptake for shrubs and grasses and how the temporal and spatial variability affects the amount and sources of water used by various species. Infiltrometer and rainfall simulation studies are being used to quantify the role of soil biota in controlling soil surface hydrology in arid and semiarid environments and to define the resistance and resilience of different soils and plant communities to different disturbance regimes. Previous work at the Jornada quantified the interception of rainfall for different shrubs and infiltration rates in root-plowed areas. Runoff was measured with a 2.8 m3/s critical depth flume on a shrub-dominated, 7.4-ha watershed from 1977-1986. These flow measurements were reactivated in 2003. Runoff and sediment measurements were also made on plots, microwatersheds, and stock ponds. Because of the aridity of the Jornada, there have been numerous rangeland rehabilitation treatments with the goal of slowing or reversing the shrub encroachment into grasslands. The most effective treatments have revolved around redistribution of surface runoff and its effects on infiltration and soil moisture. Simple, low profile, water-ponding dikes seem to have had the best success in achieving a positive vegetation response.}, url = {/files/bibliography/04-064Proc.pdf}, author = {A. Rango and K. A. Snyder and Jeffrey E. Herrick and Kris Havstad and Gibbens, Robert P. and John Wainwright and Parsons, T.} } @article {50949, title = {Hydrology-vegetation interactions in areas of discontinuous flow on a semi-arid bajada, Southern New Mexico}, journal = {Journal of Arid Environments}, volume = {51}, year = {2002}, note = {//NMSU//LTER IV//}, month = {2002}, pages = {319-338}, abstract = {

Flows on a bajada surface in the Chihuahuan Desert of New Mexico show a discontinuous pattern, with alternating areas of channelization and deposition. Based on their planform appearance, we have termed the depositional areas {\textquoteright}beads{\textquoteright}. Instrumented catchments demonstrated that in comparison to {\textquoteright}normal{\textquoteright} dendritic catchments, the beads show net infiltration in all but the largest flow events. Net accumulation of the bead surface appears to occur in years of lower than average rainfall, but the surface is dynamic and suffers net erosion in wetter years. The beads have significantly higher total vegetation covers, and contain higher proportions of grass species (Muhlenbergia porteri) as well as the creosotebush that characterizes the bajada surface in general. Creosotebush in the beads show consistently lower values of {\"a}13C, suggesting that they are less moisture stressed than creosotebush elsewhere on the bajada. Values of {\"a}15N are higher in the bead creosotebush, suggesting higher rates of soil-nitrogen transformations and greater loss of nitrogen to the atmosphere by denitrification. Both of these factors are again consistent with higher infiltration and thus moisture contents in the beads. In contrast, xylem-pressure potentials in creosotebush in the bead taken before the summer monsoonal season suggest that plants within the bead are more moisture stressed than those outwith the bead. Four possible explanations are offered for this apparent discrepancy: the greater cover and biomass of plants in the bead leads to higher stresses at the end of the drought period; spatial variability in soil texture means that some areas of the bead retain less moisture; more available water in the bead goes to the grass plants that concentrate their roots near the surface; and there is greater competition in the bead during times of drought stress. Overall, these results are compatible with an {\textquoteright}islands of fertility{\textquoteright} interpretation of desertification operating in the American Southwest, albeit on a larger spatial scale than usually attributed. The concentrations of nutrient, water and seed resources may mean that these sites are favourable for attempts to reverse the desertification process. However, they appear dynamic with life cycle of about 30 years. {\textcopyright}2002 Elsevier Science Ltd.

}, keywords = {article, articles, carbon, Larrea, hydrology, deposition, hydrology, erosion, hydrology, Larrea, hydrology, processes, hydrology, shrubs, hydrology, xylem-pressure potential, hydrology,infiltration, hydrology,runoff, journal, journals, Larrea, xylem-pressure potential, nitrogen, Larrea, plant, 13C, plant, 15N, xylem-pressure potential, hydrology}, doi = {10.1006/jare.2002.0970}, url = {files/bibliography/JRN00357.pdf}, author = {John Wainwright and A.J. Parsons and W. H. Schlesinger and Athol D. Abrahams} } @article {JRN54960, title = {Hydrological Effects of a Changed Climate in Humid and Arid Mountain Regions}, journal = {World Resource Review}, volume = {12}, year = {2000}, pages = {493508}, chapter = {493}, abstract = {

The effect of a hypothetical temperature increase of +4{\textdegree}C on snow cover and on year-round runoff is evaluated for the very humid basin Illecillewaet (1155 km2, 509-3150 m a.s.l., British Columbia, Canada), the semi-humid basin of Kings River (3999 km2, 171-4341 m a.s.l., California, USA), and the semi-arid basin of Rio Grande at Del Norte (3419 km2, 2432-4215 m a.s.l., Colorado, USA). In contrast to current methods of evaluating the climate effect, a realistic seasonal snow cover from satellite monitoring is used to represent the present climate, the non-calibrated SRM model is applied to transform this snow cover under conditions of a warmer climate to compute climate-affected runoff.

The winter snow accumulation is particularly reduced in the Kings River basin which has the greatest elevation range. In absolute terms, the smallest snowpack reduction occurred in the semi-arid basin of Rio Grande at Del Norte. The decline of snow covered area in the snowmelt season in accelerated by about one month in all basins. The runoff in the winter half year is about doubled at the expense of the summer half year in the basins Illecillewaet and Kings River. This effect is smaller in the basin Rio Grande at Del Norte. Because the climate change was limited to a temperature increase, there is no significant change in the yearly runoff volume in the basins Kings River and Rio Grande. There is a yearly runoff increase in the Illecillewaet basin due to enhanced glacier melt.

}, keywords = {climate change, glaciers, runoff, snow, water resources planning}, url = {files/bibliography/Rango2000-02.pdf}, author = {A. Rango and J. Martinec} } @proceedings {51161, title = {A helping hand: Facilitation of plant invasions by human activities}, year = {1999}, note = {// //LTER III//ProCite field[6]: In}, month = {1999}, address = {Townsville, Australia}, keywords = {abstract, abstracts, conference, conference proceedings, conferences, human impacts, human impacts, plant invasion, plant invasion, proceeding, proceedings}, author = {L. Huenneke} } @article {51180, title = {How Ecosystems Respond to Stress: Common properties of arid and aquatic systems}, journal = {BioScience}, volume = {49}, number = {3}, year = {1999}, month = {March 1, 1999}, pages = {193-203}, abstract = {

Given that regional ecosystems are unique and thus may differ considerably in their normal ranges of primary and secondary productivity, species composition, diversity, and nutrient cycling, and given that each system is exposed to unique combinations of stresses, it might be expected that patterns of response to stresses will be highly variable and unpredictable. Therefore, it is surprising to discover remarkable similarities in the response of ecosystems to stress (Odum 1985, Rapport et al., 1985; Rapport and Regier, 1995). Stressed ecosystems are characterized by a \"distress syndrome\" (Rapport et al., 1985) that is indicated not only by reduced biodiversity and altered primary and secondary productivity but also by increased disease prevalence, reduced efficiency of nutrient cycling, increased dominance of exotic species, and increased dominance by smaller, shorter-lived opportunistic species. These signs have been well documented in a number of studies of both terrestrial and aquatic systems (Hilden and Rapport, 1993; Rapport et al., 1995; Whitford, 1995; Epstein and Rapport, 1996; Wichert and Rapport, 1998). How might this distress syndrome pattern be explained? By what mechanisms do stressed ecosystems become degraded? Why has it proven so difficult to rehabilitate stressed ecosystems, even after the initial stresses have been reduced or removed altogether? In this article, we address these and related questions by an empirical examination of three very different regional ecosystems, each of which has had a long history of exposure to multiple anthropogenic and natural stresses.

}, url = {files/bibliography/99-BioScience-Whitford.pdf}, author = {D. J. Rapport and Walter G. Whitford} } @article {51181, title = {How ecosystems respond to stress: common properties of arid and aquatic ecosystems}, journal = {Bioscience}, volume = {49}, number = {3}, year = {1999}, note = {//USDA//NONE//}, month = {1999}, pages = {193-203}, abstract = {

Nearly all ecosystems are subject to periodic disturbances by natural events, such as flood, fire, drought, and insect infestation (Vogl 1980). When such perturbations are extreme, ecosystems of immense complexity undergo rapid transformation to systems of remarkable simplicity that are characterized by a scarcity of life forms and few or no symbiotic interactions. However, this transformation sets the stage for recovery, which allows the ecosystem to adapt to changing environments (Holling 1986). In healthy systems, therefore, these perturbations are seldom more than a temporary setback, and recovery is generally rapid (Odum 1969). By contrast to natural disturbances, anthropogenic stress is not a revitalizing agent, but a debilitating one. Stressed ecosystems do not recover; rather, further degradation may follow. Indeed, Odum et al. (1979) defined stress as a debilitating agent and perturbation (subsidy) as potentially beneficial.

}, keywords = {article, articles, ecosystem dynamics, shrubland, ecosystem health, rehabilitation, ecosystem health, stress, grassland, ecosystem health, journal, journals, restoration, grassland, shrubland, ecosystem health}, doi = {10.2307/1313509}, url = {/files/bibliography/519.pdf}, author = {D. J. Rapport and Walter G. Whitford} } @article {51354, title = {High foliar nitrogen in desert shrubs: An important ecosystem trait or defective desert doctrine?}, journal = {Ecology}, volume = {77}, year = {1996}, month = {1996}, pages = {1728-1737}, abstract = {

Nitrogen concentrations in green and senesced leaves of perennial desert shrubs were compiled from a worldwide literature search to test the validity of the doctrine that desert shrubs produce foliage and leaf litter much richer in nitrogen than that in the foliage of plants from more mesic environments. Mean nitrogen concentration in the green leaves of 78 species of shrubs growing in 11 deserts on five continents (2.2\%) was not different from that in 67 species of trees and shrubs growing in deciduous, and mixed deciduous forests (2.2\%), and only slightly higher than that in overstory (2.0\%) and understory (2.1\%) plants growing in tropical wet forest. Mean nitrogen concentration in the green leaves of a ubiquitous shrub that dominates large areas of desert in the United States (Larrea tridentata, 2.1\%), and in the green{\textemdash}stem tissues of leafless desert shrubs (2.1\%) were also similar to that in plants from mesic environments. Mean green{\textemdash}leaf nitrogen was similar in shrubs growing in different deserts. Mean nitrogen concentration in leaf litter was 1.1\% for 11 species of desert shrubs, and 1.0\% for the 10 species of this group that were not capable of symbiotic nitrogen fixation. Both concentrations were lower than those routinely provided to describe nitrogen in the litter of desert shrubs (1.5{\textemdash}1.7\%), and only slightly higher than the mean nitrogen concentration in 77 species of woody perennials growing in a wide variety of environments worldwide (0.9\%). Nitrogen in the leaf litter of one desert shrub (0.4\%, Brickellia laciniata) was nearly as low as the lowest leaf{\textemdash}litter nitrogen concentration known for any woody species (0.3\%). Because nitrogen concentrations in the foliage of desert shrubs are not higher than those in plants growing in more mesic environments, the tenet that desert shrubs support extraordinarily nitrogen{\textemdash}rich foliage can no longer be supported.

}, keywords = {desert shrubs, ecosystem traits, green leaves, leaf litter, nitrogen in desert shrubs, nutrient cycling}, doi = {10.2307/2265778 }, url = {/files/bibliography/495.pdf}, author = {K.T. Killingbeck and Walter G. Whitford} } @article {51473, title = {How herbivory affects grazing tolerant and sensitive grasses in a central Texas grassland: Integrating plant response across hierarchical levels}, journal = {Oikos}, volume = {67}, year = {1993}, month = {1993}, pages = {291-298}, url = {/files/bibliography/93-001.pdf}, author = {Joel R. Brown and Stuth, J.W.} } @article {51491, title = {Herbivory of clonal populations: cattle browsing affects reproduction and population structure of Yucca elata}, journal = {Oecologia}, volume = {93}, year = {1993}, month = {1993}, pages = {12-17}, abstract = {

The hypothesis that cattle browsing on inflorescences of the soaptree Yucca elata reduces reproductive success was investigated by comparing recruitment and population structure in six populations protected from grazing, six grazed during the flowering season and five grazed outside the flowering season. Cattle consumed 98\% of inflorescences, which were found to be highly nutritious. Reduced recruitment in flower-grazed populations could not be attributed to reduced flower survival, as recruitment in non-flower grazed populations was also reduced. Changes in population structure were due to cattle browsing small caudices, including both genets and ramets. An alternate hypothesis of limited germination in soils compacted by cattle was not supported. Cattle browsing of inflorescences reduced reproductive effort, which may be due to the inability of the plants to resorb nutrients after flowering. Browsing also increased branching, probably through lack of apical dominance, whereas physical trampling increased procumbency. Cattle browsing implies a lack of genetic recruitment, possible local extinction of the yucca moth Tegeticula yuccasella, the exclusive pollinator of Y. elata, and local reduction in insect and bird biodiversity.

}, keywords = {Biodiversity; Cattle; Herbivory; Nutritional value of inflorescences; Yucca elata}, doi = { 10.1007/BF00321184 }, url = {files/bibliography/93-Oecologia-Whitford.pdf}, author = {G. I. H. Kerley and Tiver, F. and Walter G. Whitford} } @article {51597, title = {Hydrologic parameters for selected soils in Arizona and New Mexico as determined by rainfall simulation}, year = {1991}, note = {//OTHER//NONE//}, month = {1991}, institution = {New Mexico Water Resources Research Institute}, address = {Las Cruces, New Mexico}, abstract = {This technical report contains the results from a study to determine hydrologic parameters for selected soils in Arizona and New Mexico. Data analyses indicate that the infiltration characteristics among the sites are quite similar. Differences can be attributed to the amount of organic ground cover on a plot, the antecedent water content of the soil prior to the experiment, and the soil{\textquoteright}s percent silt fraction. Based on visual estimates in the field, plots were designed as having "high" or "low" cover. At the two sites revisited during this study, there were no statistical differences in hydrologic parameters between the previous and current experiments. Differences which appeared to exist in the data could be attributed to soil moisture and other transient site conditions. Numerous water chemistry samples were analyzed to determine potential nutrient loadings from forest lands to water bodies. Total phosphorus and volatiles solids are related to inorganic sediment yield. Total nitrogen appears to be related to total phosphorus.}, keywords = {book, books, chapter, chapters, hydrology, model, hydrology,infiltration, hydrology,processes, hydrology,runoff plot, hydrology,sediment yield, model,hydrology, nutrients,hydrology, rainfall simulation, report, reports, soil erosion}, isbn = {Technical Completion Report No. 259}, author = {Timothy J. Ward and S. M. Bolton} } @mastersthesis {51691, title = {Hydrologic and edaphic patterns and processes leading to playa flooding}, year = {1989}, note = {//NMSU//LTER I//}, month = {1989}, pages = {91}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {A conceptual model of the hydrologic patterns and processes leading to the flooding of College Playa was developed. College Playa is a small, freshwater, desert playa located on the Jornada Long Term Ecological Research site and the New Mexico State University College Ranch. This model was based on an 18-year record of flooding of College Playa and the rainfall occurring on its watershed. College Playa{\textquoteright}s watersheds soils and major landforms were also considered in the model development. Several essential features of the model are that (1) College Playa may flood due to as little as 25 mm of rainfall if there is a 0.5 hr period with an intensity of 25mm/hr at some time during the storm, but (2) the rainfall must occur at or near the playa basin, and (3) runoff from the upland areas of the watershed{\textquoteright}s fan piedmont is not necessary for the playa to flood. The arrangement of playa basin soils is consistent with the observed high frequency of only partial flooding of the playa basin. The proposed conceptual model was examined using MULTSED, a mathematical, watershed level, physically based, rainfall-runoff event model. The essential features of the conceptual model were preserved in the mathematical model. The conceptual model may be applicable, at least qualitatively, to many other playas. However, the rainfall and flooding records necessary to investigate the applicability of the model to other playas are not available. Following from the proposed conceptual model, sediment and detritus sources in and near the playa basin have greater influence on playa water chemistry, and consequently on playa aquatic community structure and dynamics, than more distant, upland sediment and detritus sources.}, keywords = {dissertation, dissertations, flooding,playa, hydrology, playa flooding, model, playa flooding, playa, flooding, theses, thesis, transect, playa flooding}, author = {Steven Scott Van Vactor} } @article {51756, title = {Heifer disposition and bonding of lambs to heifers}, journal = {Applied Animal Behavior Science}, volume = {19}, year = {1987}, note = {Reprinted with permission from Elsevier, {\textcopyright} 1987. http://www.sciencedirect.com/science/journal/01681591}, month = {1987}, pages = {27-30}, abstract = {

Abusive and non-abusive (tolerant) heifers were individually identified during pen confinement with young sheep. Physical aggression by abusive heifers toward lambs included butting and kicking. Two groups of three 75-day-old lambs confined with tolerant heifers developed a bond after 20 days and a strong bond after 55 days. However, three lambs confined with abusive heifers were not bonded at 20 days, but formed a satisfactory bond with the cattle after 55 days as the cattle became more tolerant of the lambs. During pen confinement, lambs with abusive heifers spent 41\% of the time in a creep area away from heifers. In contrast, lambs in two tolerant lamb-heifer groups spent only 15\% of their time in the creep area. Heifers which are abusive to lambs should be identified and removed from lamb heifer groups if bonding is to be accomplished consistently and efficiently.

}, doi = {10.1016/0168-1591(87)90199-7}, url = {/files/bibliography/307.pdf}, author = {D.M. Anderson and Clarence V. Hulet and J. N. Smith and Shupe, W. Larry and L. W. Murray} } @proceedings {51801, title = {How desertification affects nitrogen limitation of primary production of Chihuahuan Desert watersheds}, volume = {General Technical Report RM-150}, year = {1987}, note = {//NMSU//LTER I//Listed in LTER2 proposal as citing LTER1 support//ProCite field[6]: In}, month = {Octoer 12-16, 19}, pages = {143-153}, publisher = {USDA Forest Service}, address = {Tucson, Arizona}, abstract = {It is hypothesized that the shift from perennial clump grasses to shrub dominated ecosystems in the Chihuahuan Desert has resulted in a change from predominantly water limited ecosystems to nitrogen-water limited ecosystems. In shrublands nitrogen and water are concentrated in patches under individual shrubs. This patchiness affects the temporal linkage between water inputs and nitrogen availability. Nitrogen and water availability are also affected by redistribution of organic matter by wind, water and animals. Shifts from grassland to shrubland results in increased temporal and spatial variability of these essential resources for plant production. Models for predicting primary productivity on desert landscapes must include linkage between mechanistic nitrogen models and broad spatial scale organic matter transport and accumulation models.}, keywords = {abstract, abstracts, conference, conference proceedings, conferences, desertification,primary production, model, desertification, model,primary production, nitrogen,primary production, primary production,nitrogen, proceeding, proceedings}, author = {Walter G. Whitford and J. F. Reynolds and Gary L. Cunningham}, editor = {Earl F. Aldon and Carlos E. Gonzale Vicente and Moir, William H. (eds.)} } @article {51803, title = {A hierarchical classification of landforms: some implications for understanding local and regional vegetation dynamics}, year = {1987}, note = {//NMSU//LTER I//Listed in LTER2 proposal as citing LTER1 support//ProCite field[6]: In}, month = {1987}, pages = {15-23}, institution = {USDA Forest Service, Rocky Mountain Forest and Range Experiment Station}, address = {Fort Collins, Colorado}, abstract = {

Analyses of soils and vegetation on the Jornada/Long-Term Ecological Research site have shown strong relationships between vegetative communities and landforms. Observations indicate that similar vegetative patterns exist throughout the Mexican Highland division of the Basin and Range Province. A generalized landscape-level model is presented which attempts to explain the desertification trends producing the shrub-grassland vegetational mosaic found today in southern New Mexico.

}, keywords = {book, books, chapter, chapters, community, landforms, community, vegetative, desertification, geomorphology, transect, geomorphology, vegetation dynamics, landforms, classification, model, desertification, report, reports, transect, geomorphology, transect, landforms, transect, plant communities, transect, vegetation dynamics, vegetation dynamics, vegetation, classification, vegetative communities}, isbn = {General Technical Report RM-150}, url = {files/bibliography/JRN00048.pdf}, author = {Steven M. Wondzell and Gary L. Cunningham and Dominique Bachelet}, editor = {Earl F. Aldon and Carlos E. Gonzale Vicente and Moir, William H. (eds.)} } @article {51845, title = {High-resolution climatic analysis and southwest biogeography}, journal = {Science}, volume = {232}, year = {1986}, note = {//LOCAL, USDA//NONE, LTER//}, month = {1986}, pages = {27-34}, abstract = {

A method that allows year-to-year patterns of weather variability to be characterized in the contexts of global warming and cooling trends in applied in a combined analysis of long-term monthly weather records and data from an ecological monitoring project in southern New Mexico. The analysis suggests a cause-effect hypothesis of recent decertification in the North American Southwest. The links between the atmosphere and the biosphere are based on the fundamentally different responses to specific weather regimes of semidesert grasses with a C4 photosynthetic pathway and desert shrubs with a C3 photosynthetic pathway. The hypothesis appears to be of sufficient generality to explain the complex, but well-documented, floristic changes that have occurred in the same region since the last glacial maximum.

}, keywords = {article, articles, biogeography, global climate, climate, analysis, climate, global, climate, vegetation response, grassland,climate, journal, journals, seedling establishment, Bouteloua,seedling establishment, vegetation response,climate}, doi = {10.1126/science.232.4746.27 }, author = {R. M. Nielson} } @article {51867, title = {A hand-portable, single nozzle, rainfall simulator designed for use on steep slopes}, journal = {Journal of Range Management}, volume = {39}, number = {4}, year = {1986}, note = {Permission to post articles granted by the Society for Range Management; www.rangelands.org.}, month = {July 1, 1986}, pages = {375-377}, abstract = {

The objective of this study was to develop a small plot (1m2) rainfall simulator operational on steep terrain in the Guadalupe Mountains of New Mexico. The simulator developed is hand-portable and consists of a spray head assembly mounted on 3 adjustable legs. A 946-liter tank equipped with a gasoline powered pump was connected to the spray head assembly via rubber garden hoses. On steep slopes gravity provided sufficient pressure to operate the simulator. Site selection was limited to areas where the water tank could be located in a suitable upslope position. The simulator has been used for 2 years on 170 plots and has proved durable. Advantages of this device are the low cost of construction and operation, and the flexibility in plot-site selection it provides. The principal disadvantages are associated with the single stationary nozzle, such as uneven application of water at small drop sizes and low kinetic energies.

}, doi = {10.2307/3899784 }, url = {/files/bibliography/304.pdf}, author = {Wilcox, B.P. and Wood, M. K. and J.M. Tromble and Timothy J. Ward} } @article {51878, title = {Host plant ovipositional preferences and usage by Oecleus nolinus (Homoptera: Cixiidae)}, journal = {The Southwestern Naturalist}, volume = {30}, number = {4}, year = {1985}, note = {//NMSU//NONE//}, month = {1985}, pages = {610-611}, abstract = {

During May and June , 1979, we observed large numbers of O. nolinus at the Jornada Experimental Range, 60 km NNE of Las Cruces, Dona Ana Co., New Mexico. They used three plant species (Yucca baccata, Y. elata and Dasyliron wheeleri) as ovipostional sites. Dasyliron wheeleri is an apparent new host for O. nolinus. Townsend (Psyche 6:353-354, 1928) recorded an Oecleus, probably O. nolinus but recorded as O. decens, ovipositing on Yucca angustifolia (=Y. elata?) and Y. macrocarpa (=Y. baccata?) in southern New Mexico.

}, keywords = {article, articles, Dasylirion,ovipositional site, insect, Oecleus, invertebrate, Homoptera, journal, journals, Oecleus,ovipositional sites, Oecleus,reproduction strategy, plant, Dasylirion, plant, Yucca, Yucca,ovipositional site}, url = {files/bibliography/85-SWNat-Whitford.pdf}, author = {Harold G. Fowler and Walter G. Whitford} } @article {51952, title = {Herbicide treatment and vegetation response to treatment of mesquites in southern New Mexico}, journal = {Journal of Range Management}, volume = {36}, number = {2}, year = {1983}, note = {Permission to post articles granted by the Society for Range Management; www.rangelands.org.}, month = {March 1, 1983}, pages = {149-151}, abstract = {

Mesquite (Prosopis juliflora) is a major unwanted plant in the Southwest. This study evaluated the herbage responses obtained from various aerial applications of 2,4,5-T on mesquites in southern New Mexico. The dead plants on the various areas ranged from 7-64\% of the mesquite. Yields of perennial grasses ranged from 3-1931 kg/ha on the untreated controls and 11-2696 kg/ha on the areas sprayed with 2,4,5-T. In dense stands of mesquite, about 30\% of the mesquites must be killed before grass yields are significantly increased.

}, url = {/files/bibliography/238.pdf}, author = {C.H. Herbel and W. L. Gould and Leifeste, W L. and Gibbens, Robert P.} } @article {52006, title = {Habitat selection and community matrix of a desert small-mammal fauna}, journal = {Ecology}, volume = {63}, number = {5}, year = {1982}, note = {//NMSU//US-IBP//}, month = {1982}, pages = {1400-1410}, abstract = {This study considers several questions about interspecific competition and habitat use by desert small mammals. From 1971 through 1973, rodent population data were collected by live-trapping on a creosote bush bajada located near Las Cruces, New Mexico, USA. At each trap station, measurements of the vegetation were taken to provide a description of the microhabitat surrounding each station. Multiple regression analysis was used to estimate the effects of competition and habitat selection in determining the local distributions and abundances of the rodent species in each year. The 10 species form four guilds: (1) Onychomys arenicola, (2) Neotoma albigula and N. micropus, (3) Dipodomys merriami and D. ordii, and (4) Perognathus intermedius, Pg. penicillatus, Peromyscus eremicus, P. maniculatus, and P. leucopus. None of the competition estimates for between-guild interactions was significantly negative, indicating that a species in one guild was attributable in some cases to differences in food and habitat preferences, and in others to differences in foraging methods related to body size. Competition was not observed within the Dipodomys guild because of the different microhabitat specializations of the two species. The three Perognathus spp. appear to avoid competition with each other by complementary habitat use; competition was observed within the Peroganthus-Peromyscus guild, but only among Perognathus intermedius, Pg. penicillatus, and Peromyscus eremicus. The magnitudes of the observed competitive interactions varied significantly from year to year with changes in both rodent densities and resource availabilities. The competitive relationships within the guild were consistent, however, and the three species were ranked in increasing competitive ability: Perognathus penicillatus<Perognathus intermedius <Peromyscus eremicus. Some evidence suggests that competitive ability increases with increasing habitat specialization.}, keywords = {article, articles, journal, journals, rodent community, rodent, competition, rodent, habitat selection, small mammal, SEE }, author = {Hallett, James G.} } @article {52014, title = {Herbage dynamics and primary productivity of a desert grassland ecosystem}, year = {1982}, month = {December 1982}, pages = {1-43 }, address = {Las Cruces}, abstract = {

Lindeman{\textquoteright}s ( 1942) paper on trophic-dynamic aspects of ecology ignited interest in ecological relationships at the ecosystem level. The development of high-speed computers enabled ecologists to analyze complete ecosystems and to model them (Van Dyne 1966). These interests and activities have culminated in the International Biological Program (IBP) Analysis of Ecosystems. The primary objective of the Analysis of Ecosystems portion of the IBP is to understand the basis of productivity worldwide. This bulletin deals with herbage dynamics and primary production of a desert grassland ecosystem. Primary production is important in any ecosystem; it fuels consumer and decomposer groups. Products from primary production also influence abiotic parameters. Litter on the soil surface influences infiltration rates and, as it is incorporated into the soil, changes physical and chemical soil properties. Many studies have been concerned with desert grassland vegetation and have analyzed end-of-season standing crop of certain groups of plant species, but few have analyzed the details of herbage dynamics, primary production, and energy dynamics of primary producers under desert grassland conditions.

}, url = {/files/bibliography/222.pdf}, author = {Pieper, Rex D. and C.H. Herbel} } @mastersthesis {52074, title = {Habitat influence on population densities of range caterpillar, Hemileuca oliviae ckii.}, year = {1980}, note = {//??//NONE//}, month = {1980}, pages = {67}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, keywords = {arthropod, Hemileuca, arthropod, range caterpillar, population density, dissertation, dissertations, Hemileuca,population density, range caterpillar,population density, theses, thesis}, author = {Beavis, William Dale} } @mastersthesis {52124, title = {Host specificity in the Yucca moth, Tegeticula yuccasella complex (Lepidoptera: Incurvariidae): A morphometric approach}, year = {1979}, note = {//LOCAL//NONE//}, month = {1979}, pages = {48}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {Four hundred and fifty-eight individuals presently grouped with Tegeticula yuccasella were collected from flowers of Yucca baccata, Yucca elata, and Yucca torreyi from Dona Ana County, New Mexico. A morphometric analysis using characters of the wings and genitalia, and color of the antennae were carried out on 225 individuals. The data were separated into three groups based on plant host species and analyzed using a stepwise discriminate analysis. Significant separation between the tree groups resulted with only two misclassifications. Characters which best separated the groups included wing length, color of the antennae, length of the male genitalia, width of the saccus, length of the aedeagus, diameter of the signum, and height of the base of the ovipositor. Three species were described and compared based on the analysis, although it was not possible to determine if one of these is a subspecies of T. yuccasella. For this reason, no new specific names are given.}, keywords = {dissertation, dissertations, insect,Tegeticula, insect,Yucca moth, Tegeticula, host specificity, theses, thesis, Yucca moth, SEE 2 hybrid of Gossypium barbadense x gossypium hirsutum via the semigametic haploid method}, journal = {Crop Science}, volume = {16}, year = {1976}, month = {May-June 1976}, pages = {441-442}, keywords = {haploid, hybrid, semigametic}, url = {/files/bibliography/99-008.pdf}, author = {J.R. Barrow and H. K. Chaudhari} } @proceedings {52375, title = {Herbage dynamics and net primary production in certain ungrazed and grazed grasslands of North America}, year = {1971}, note = {//USDA//US-IBP//NMSU library QH541.5 .P7 .P74//ProCite field[6]: In}, month = {September 1, 197}, pages = {59-124}, publisher = {Colorado State University}, address = {Colorado State University, Fort Collins, Colorado}, abstract = { Nine U.S. IBP Grassland Biome sites are characterized according to the abiotic and vegetational characteristics and their relationship to grazed and ungrazed conditions by analysis and synthesis of 1970 field data. Abiotic characteristics including length of growing season, usable solar radiation, mean annual temperature, mean annual precipitation, potential and actual evapotranspiration, and aridity indices are used to interpret intraseasonal herbage dynamics and net primary productivity. Snythesis of vegetation data involved categorization of plant species into cool and warm season vegetation classes (grasses, forbs, shrubs, and succulents) and into compartments by live, current year{\textquoteright}s dead, old dead, litter, and belowground plant meterial. The belowground biomass is characterized according to the seasonal average and peak biomass, percentage of total plant biomass situated belowground, and the vertical distribution of this material. Annual increment and turnover rates are presented. The relationship of these charcteristics to abiotic factors is examined. Estimated net primary productivity and accumulation rates are calculated for ungrazed and grazed grasslands on each site. These data are further analyzed by evaluation of system transfer functions and efficiency of energy capture by various vegetation compartments.}, keywords = {abstract, abstracts, biomass,grassland, conference, conference proceedings, conferences, grassland,abiotic factors, grassland,biomass, grassland,herbage dynamics, grassland,primary production, grazing,herbage dynamics, grazing,primary production, primary production,grassland, proceeding, proceedings}, author = {P. L. Sims and Singh, J. S.}, editor = {Norman R. French} } @article {52382, title = {Heterozygosity in inheritance of verticillium wilt tolerance in cotton}, journal = {Phytopathology}, volume = {60}, number = {2}, year = {1970}, month = {February 1970}, pages = {301-303}, keywords = {cotton, heterozygosity, inheritance, verticillium}, url = {/files/bibliography/99-003.pdf}, author = {J.R. Barrow} } @mastersthesis {52395, title = {Habitat preference of the desert cottontail with additional notes on the black-tailed jack rabbit}, year = {1970}, note = {//LOCAL//NONE//}, month = {1970}, pages = {26}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {The habitat preference of the desert cottontail (Sylvilagus audubonii) was examined along with that of the black-tailed jack rabbit (Lepus californicus). The study was conducted within the northwestern portion of the Chihuahuan Desert, four road miles northeast of New Mexico State University, Las Cruces, from late September, 1969, to early March, 1970. Preferences for two shrub habitats were compared, one relatively open at the ground level, the other with denser ground vegetation. The cottontail was found to prefer the habitat with the denser cover of low-hanging, spreading shrubs. This was apparently due to a need for a close interspersion of low-hanging vegetation useable for escape cover and for concealment when resting. For the jack rabbit, a preference was also indicated for the denser shrub habitat, but it made nearly as much use of the other shrub habitat with the lesser amount of low-hanging vegetation. Both habitats had abundant open spaces used for flight by the jack rabbit.}, keywords = {black-tailed jack rabbit, SEE Lepus, desert cottontail, SEE Sylvilagus, dissertation, dissertations, habitat preference, Lepus, habitat preference, Sylvilagus, habitat preference, theses, thesis}, author = {Legler, Randall Phar , Jr.} } @mastersthesis {52407, title = {Habitat, annual cycle and food of burrowing owls in Southcentral New Mexico}, year = {1969}, note = {//LOCAL//NONE//}, month = {1969}, pages = {34}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {Burrowing Owls were studied in Dona Ana and Luna counties of southcentral New Mexico from March, 1964 until November, 1967. Six major study areas were established and observations were made throughout this area. Evidence indicated that the habitat of Burrowing Owls was dependent on the time of year, the breeding status of the birds, and whether the breeding birds were in isolated pairs or groups. Therefore, habitat factors varied between solitary owls, single breeding pairs, and colonies. The solitary owls were found to be practically unrestricted in habitat. Single breeding pairs were found in small isolated areas of colony habitat. Colonies were restricted to yucca grassland with burrows of Dipodomys spectabilis. The daily activity periods varied from nocturnal in winter to diurnal in summer. Seasonal activities such as courtship, nest preparation, nesting, rearing of young, colony break-up, molt, and migration were studied and a general timetable for these events is presented. Food was studied using the owl pellets as an indicator. It was found that the major food taken from summer through fall was insects and arachnids. Mammals and reptiles were also eaten, but in lesser amounts. Variations in diet were found generally to correlate with variations of abundance of prey species.}, keywords = {behavior,birds, bird, also SEE common name, bird, Burrowing owl, Burrowing owl, food, Burrowing owl, habitat, Burrowing owl,life cycle, dissertation, dissertations, theses, thesis}, author = {Best, Terrence Rafferty} } @article {52409, title = {Herbicide evaluation studies for the control of tarbush (Flourensia cernua)}, year = {1969}, month = {1969}, pages = {27}, institution = {Research Progress Report, Western Society of Weed Science}, abstract = {

Tarbush is a deciduous desert species which is found in dense stands on silty or clay loam sites on flood plains. The date of leaf emergence is dependent upon adequate soil mosture, so in some droughty years it may not leaf out until the summer rains occur. The studies reported were carried out on the Jornada Experimental Range near las Cruces, New Mexico, from 1961 through 1965 to determine the best time for treatment and the best herbicides for selective control. Treatments were applied semi-monthly on 1/100 A plots using a simulated aerial application from July through October in 1961 and 1965. Treatments were initiated in August 1962, on May 7, 1963, and on June 3, 1964. Defoliation estimates were made approximately 2 years after treatments were applied. The 1961 treatments included 2,4-D, 2,4-DP, 2,4,5-T, silvex, 2,3,6-TBA and amitrole-T at 1/2 lb/A. Dicamba was added to the list of test materials in 1962 and picloram was added in 1963. Herbicides were applied on all spray dates at 1/2 lb/A in 1962, 1 lb/A in 1963 and 1 1/2 lb/A in 1964 and 1965. Additional treatments with higher rates of herbicides were applied on one spray date ind 1962, 1963 and 1964. The defgree of defoliation was quite variable between dates of application with the September treatments being most toxic generally. At rates up to 2 lb/A, the phenoxy herbicides and amitrole-T usually gave less than 30\% defoliation. Dicamba was the most toxic material, causing 70\% defoliation on one or more spray dates each year. Increasing the rate of dicamba from 1/2 to 2 lb/A increased the degree of defoliation only when treatment was not on the optimum date. At comparable rates, picloram and 2,3,6-TBA were much less effective than dicamba.

}, keywords = {control, evaluation, Flourensia cernua, herbicide, tarbush}, url = {/files/bibliography/113.pdf}, author = {W. L. Gould and C.H. Herbel} } @book {52427, title = {Heart rate and changes in body fluids in aestivating toads from xeric habitats}, series = {Physiological Systems in Semiarid Environments}, year = {1969}, note = {//LOCAL//NONE//ProCite field[6]: In}, month = {1969}, pages = {125-133}, publisher = {University of New Mexico Press}, organization = {University of New Mexico Press}, address = {Albuquerque, New Mexico}, abstract = {Mayhew (1965) reported that in parts of California the spadefoot toad Scaphiopus couchi is forced to remain underground for more than 1 year. It is apparent that anurans inhabiting desert environments must have evolved some mechanisms to survive for extended periods of time in underground burrows. Some of the adaptations of the spadefoot toad S. couchi were studied by McClanahan (1967). He found that emerging S. couchi had high concentrations of urea in their body fluids and that water loss in dehydration was principally from interstitial fluids. My studies of burrowed desert anurans were designed to evaluate gross metabolic changes by monitoring heart rate and to observe changes in body fluids during aestivation. These studies should serve as the basis for further studies on the adaptive mechanisms of desert anurans.}, keywords = {amphibian, aestivating toad, anuran, aestivation, anuran, metabolism, book, books, Bufo,physiology, chapter, chapters, metabolism, aestivating toad, physiology,anuran, report, reports, Scaphiopus,physiology}, author = {Walter G. Whitford}, editor = {Hoff, C. C. and Riedesel, M. L. (eds.)} } @mastersthesis {52491, title = {Habitat analysis of the genus Neotoma in southern Rio Grande Valley, New Mexico}, year = {1965}, note = {//LOCAL//NONE//}, month = {1965}, pages = {31}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {The habitat relationships of the white-throated woodrat (Neotoma albigula albigula) and the plains woodrat (Neotoma micropus canescens) were studied in the Rio Grande Valley of southern New Mexico from May, 1964, to August, 1965. These two species of woodrats were found coexisting where they had been described in different habitats in 1907. Alterations in vegetation caused by farming and ranching practices appear to be the cause of the breakdown in habitat separation of the woodrats. The carrying capacity in woodrat habitat is probably determined by food in this area. Woodrats are absent where Yucca elata is absent, except in the foothill arroyos. Wherever Neotoma micropus was found, N. albigula was also found in this study. However, albigula was found in the apparent absence of micropus in some areas.}, keywords = {dissertation, dissertations, Neotoma,distribution, Neotoma,habitat, rodent, woodrat, rodent,Neotoma, theses, thesis}, author = {Wright, Michael E.} } @mastersthesis {52503, title = {Heritabilities and correlations between traits in Hereford steers}, year = {1963}, note = {//NMSU//NONE//}, month = {1963}, pages = {75}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {Seventy-eight weanling Hereford steers were randomized by sires and weight into 10 lots form 1960 to 1962. After a feeding period of about 224 days, the steers were weighed, various body measurements were taken, and the steers slaughtered by lots. Slaughter and carcass data were obtained. Simple correlations and two sets of partial correlations independent of slaughter age and slaughter weight were computed within yearlots. Slaughter weight, slaughter grade, and circumference of chest were highly related to most live and carcass traits, slaughter weight being the most important measure of pounds of retail trimmed high priced cuts. Among carcass characters, weight and grade measurements were found to be most indicative of carcass merit, with carcass weight exerting the greatest influence on most carcass traits.}, keywords = {cattle, genetics, cattle, management, cattle, productivity, dissertation, dissertations, genetics,cattle, productivity, also SEE , theses, thesis}, author = {Sciacca, Carl Eugene} } @article {52518, title = {A hydrocephalic lethal in Hereford cattle}, journal = {Journal of Heredity}, volume = {60}, year = {1959}, note = {//??//NONE//(New Mexico Agr. Exp. Station Journal Article 115)//}, month = {1959}, pages = {143-148}, keywords = {article, articles, cattle,disease, disease,cattle, journal, journals}, author = {Blackwell, R. L. and Knox, J. H. and Cobb, E. H.} } @article {52523, title = {Hand-grubbing mesquite in the semidesert grassland}, journal = {Journal of Range Management}, volume = {11}, number = {6}, year = {1958}, note = {Permission to post articles granted by the Society for Range Management; www.rangelands.org.}, month = {November 1, 1958}, pages = {267-270}, abstract = {Honey mesquite (Prosopisjuliflora var. glandulosa Torr.) has become an ever-increasing problem on the semidesert grassland. The semidesert grassland occupies an extensive area in southeastern Arizona, southern New Mexico, western Texas and northern Mexico. On the Jornada Experimental Range in southern New Mexico, mesquite-dominated land has increased from 13 percent of the total in 1915 to 36 percent of the total in 1946 and 49 percent in 1957. This has occurred on land that has a history of conservative grazing use and even on some large areas under complete protection. While heavy grazing use will accelerate the spread of mesquite, the complete absence of grazing use will not prevent that spread. Grubbing light stands of young mesquite plants is the most economical means of controlling mesquite. A large-scale mesquite control program was initiated on the Jornada Experimental Range early in 1958 to make information available to ranchers in the area on the costs and techniques of control measures. The area hand-grubbed was 4,265 acres located in three different pastures.}, keywords = {hand-grubbing, honey mesquite, problem, Prosopis juliflora var. glandulosa Torr., semidesert grassland}, url = {/files/bibliography/080.pdf}, author = {C.H. Herbel and F.N. Ares and Bridges, J. O.} } @article {52535, title = {Heritability of intensity of red color in Hereford cattle}, journal = {Journal of Heredity}, volume = {63}, year = {1952}, note = {//??//NONE//(New Mexico Agr. Exp. Station Journal Article 69)//}, month = {1952}, pages = {15-17}, keywords = {article, articles, cattle, genetics, journal, journals}, author = {Koger, M. and Mankin, J. D.} } @article {52586, title = {How to keep and increase black grama on Southwestern ranges}, year = {1939}, month = {1939 (Revised 19}, pages = {8 }, publisher = {U.S. Government Printing Office}, abstract = {Black grama (Bouteloua eriopoda), also known locally as woolly-foot or crowfoot grama, is by far the most important forage grass on the 89 million acres of semidesert grasslands in Arizona, New Mexico, southwestern Texas, and southern Utah. Although not as common now as in early clays, black grama can be maintained on the range and even brought back by management based on careful consideration of its forage and soil-protection values, its methods of spreading, and its ability to stand up under drought and grazing. As a prime indicator of range utilization, black grama ranks second only to blue grama (Bouteloua gracilis) over the entire Southwest. The two sometimes occur together in mixed stands, but blue grama typically grows in pinon-juniper woodlands and on the heavier soils of the shortgrass plains, whereas black grama is found on the better-drained soils in the shortgrass country and the warmer and lower semidesert grasslands. Black grama may be easily distinguished from other gramas by its widely creeping runners or stolons which root at the joints and send up new shoots that later become separate plants.}, keywords = {black grama, Bouteloua eriopoda, forage grass, government publication, semidesert grasslands}, url = {/files/bibliography/047.pdf}, author = {R.S. Campbell and Crafts, E.C.} } @article {52596, title = {Height-volume distribution in range grasses}, journal = {Journal of Forestry}, volume = {36}, number = {12}, year = {1938}, month = {December 1938}, pages = {1182-1185}, abstract = {There are 137 million acres of usable range in Arizona and New Mexico, and livestock production is an outstanding industry in the Southwest. Basic resources of this industry are the soils and the vegetation they support. Continued production of range grasses is, in large measure, dependent on forage utilization. The importance of knowing what constitutes proper use of a given kind of grass and of having an accurate method of measuring its utilization becomes evident when one realizes that a 10 percent variation in the use of the herbage volume may result in continued productivity or gradual death of the plant.}, keywords = {continued production, forage utilization, range grasses}, url = {/files/bibliography/052.pdf}, author = {Crafts, E.C.} } @article {52604, title = {How better utilization of range was obtained through the use of inexpensive water holes}, journal = {The Cattleman}, volume = {23}, number = {1}, year = {1936}, month = {1936}, pages = {21-22}, abstract = {Although improvement in quality of commodity produced is one of the principal objectives in all lines of business, control of cost of production usually goes hand in hand with such an aim in any successful business enterprise. Leading cattlemen of the Southwest have discovered, during the lean years since the World War, that a speaking acquaintance must at all times be maintained with Cost of Production if profit is to be realized. During this period, sharp competition for range entered the field and this, with low cattle prices prevailing most of the time, has forced the industry to adopt more intensive methods with closer study of investments and returns by operators.}, keywords = {inexpensive water holes, intensive methods, profits, range utilization}, url = {/files/bibliography/031.pdf}, author = {F.N. Ares} } @article {52603, title = {How the use of salt obtains better forage utilization on a cattle range}, journal = {The Cattleman}, volume = {23}, number = {12}, year = {1936}, month = {1936}, pages = {20-22}, abstract = {A lamentable condition commonly surrounds watering places on the low, year-long grass ranges of the Southwest. Areas extending for as much as one mile or more around these watering places are common on poorly watered ranges. These areas are stripped and grubbed of all worthwhile vegetation; and, they are washed and trampled and the loose sand and dust are played with by the winds. A few miles out from water on a given range, one may find areas with good forage practically untouched. Too many cattle and widely distributed stock waters have been blamed for the deteriorated conditions around watering places. Without doubt, they are contributing factors, but the fact remains that loss of valuable forage grasses has been sustained even on ranges where the watering places have been well located, as compared with the ordinary water situation on such ranges and on which stocking consistent with the conservative use of the range as a whole has been in effect.}, keywords = {better forage, cattle range, conservative use, salt}, url = {/files/bibliography/032.pdf}, author = {F.N. Ares} } @article {52605, title = {How closely may black grama and tobosa grass be grazed year after year}, journal = {The Cattleman}, volume = {23}, number = {7}, year = {1936}, month = {1936}, pages = {15-18}, abstract = {Livestock production in the semi-desert grasslands of western Texas, southern New Mexico, and southeastern Arizona was introduced by the early Spanish settlers. These pioneer people were quick to realize the adaptability of the country to grazing cattle and, thus, laid the cornerstone of one of the most colorful and successful enterprises on the Southwest, one which has survived to this day as a major industry. However, if the stockmen are to enjoy the benefits of these ranges in perpetuity, the intensity of grazing use applied on them must be one which will allow the principal forage plants to maintain themselves naturally upon the land. Not only must the good forage plants be preserved, but the yield of forage therefrom must be sustained. These conditions can only take place on properly stocked and otherwise properly managed ranges. The chief hazards of the cattle industy, namely, heavy death loss in time of drought and low percentage in calf crops, are obviously intensified by overstocking. Therefore, the solutions to the fundamental problems in range management of the semi-desert grasslands begin with the proper care of the range itself and the maintenance of a plentiful supply of forage at all times.}, keywords = {black grama grass, intensity of grazing, preservation, proper management, tobosa grass}, url = {/files/bibliography/033.pdf}, author = {Canfield, R.H.} }