@article {JRN55321, title = {Long-term research catchments to investigate shrub encroachment in the Sonoran and Chihuahuan deserts: Santa Rita and Jornada experimental ranges}, journal = {Hydrological Processes}, volume = {35}, year = {2021}, month = {January 2021}, pages = { e14031}, abstract = {Woody plant encroachment is a global phenomenon whereby shrubs or trees replace grasses. The hydrological consequences of this ecological shift are of broad interest in ecohydrology, yet little is known of how plant and intercanopy patch dynamics, distributions, and connectivity influence catchment-scale responses. To address this gap, we established research catchments in the Sonoran and Chihuahuan Deserts (near Green Valley, Arizona and near Las Cruces, New Mexico, respectively) that represent shrub encroachment in contrasting arid climates. Our main goals in the coordinated observations were to: (1) independently measure the components of the catchment water balance, (2) deploy sensors to quantify the spatial patterns of ecohydrological processes, (3) use novel methods for characterizing catchment properties, and (4) assess shrub encroachment impacts on ecohydrological processes through modeling studies. Datasets on meteorological variables; energy, radiation, and CO2 fluxes; evapotranspiration; soil moisture and temperature; and runoff at various scales now extend to nearly 10 years of observations at each site, including both wet and dry periods. Here, we provide a brief overview of data collection efforts and offer suggestions for how the coordinated datasets can be exploited for ecohydrological inferences and modeling studies. Given the representative nature of the catchments, the available databases can be used to generalize findings to other catchments in desert landscapes.}, keywords = {Chihuahuan deserts, Jornada experimental ranges, Long-term research catchments, Santa Rita, shrub encroachment, Sonoran}, doi = {10.1002/hyp.14031}, url = {files/bibliography/21-044.pdf}, author = {Enrique Vivoni and Eli R. Perez and Zachary T Keller and Eric Escoto and Ryan Templeton and Nolie P Templeton and C.A. Anderson and A. P. Schreiner-McGraw and Luis A. M{\'e}ndez-Barroso and Agustin Robles Morua and R.L. Scott and Steven R. Archer and Debra C. Peters} } @article {JRN54224, title = {Responses of a desert nematode community to changes in water availability}, journal = {Ecosystems}, volume = {6}, year = {2015}, chapter = {Article 44}, abstract = {

The most recent climate models unequivocally predict a strong drying trend for the southwestern USA within the next century. Soil nematodes are a highly important component of desert ecosystem functioning, but rely on water films formovement. However, it is currently poorly understood how different trophic groups of nematodes respond to chronic presses as well as short-lived pulses of altered water availability, especially in arid systems where such changes are expected to have the greatest impact. The aim of this study was to assess the effects of both instantaneous and long-term variation in water availability on desert soil nematode trophic groups.We hypothesized that nematode abundance would respond positively to both short- and long-term increases in moisture. Based on the ecology of the different trophic groups we further made predictions about their relative rates of response. We increased or decreased precipitation from ambient levels in the Chihuahuan Desert for four consecutive years and sampled soil nematodes after two, three and four years. We tested the effects of altered precipitation treatments through time as well as gravimetric soil moisture at the time of sampling on the abundance of the different nematode trophic groups. In contrast to our hypotheses, the abundances of most nematode trophic groups were unaffected by the amount of precipitation, even after four years of altered precipitation. Plant-parasitic nematodes from low moisture soils were the only group that reacted positively to increased precipitation from the third year onwards. Trophic groups responded differently to soil moisture, with bacterivores decreasing with increasing moisture and omnivores showing a positive relationship that diminished over time. We show that in general, these desert nematodes were not limited by precipitation, and were highly resilient to decreases therein. However, when also considering the effects of soil moisture, some more complex patterns and differences among trophic groups emerged.We discuss potential mechanisms explaining these observations and contrast our findings with those from other ecosystems around the world. We conclude that deserts harbor nematode communities that seem more resilient to altered water availability than other ecosystems.

}, keywords = {drought, nematodes, precipitation, resilience, soil ecology, soil moisture, trophic groups, water availability}, doi = {10.1890/ES14-00319.1}, url = {files/bibliography/JRN00643.pdf}, author = {Vandegehuchte, Martin L. and Sylvain, Zachary A. and Lara Reichmann and Cecilia M. de Tomasel and Nielsen, Uffe N. and D.H. Wall and O. E. Sala} } @article {JRN54297, title = {Ecohydrology with Unmanned Aerial Vehicles}, journal = {Ecosphere}, volume = {5}, year = {2014}, chapter = {art130}, abstract = {

High-resolution characterizations and predictions are a grand challenge for ecohydrology. Recent advances in flight control, robotics and miniaturized sensors using unmanned aerial vehicles (UAVs) provide an unprecedented opportunity for characterizing, monitoring and modeling ecohydrologic systems at high-resolution (\<1 m) over a range of scales. How can the ecologic and hydrologic communities most effectively use UAVs for advancing the state of the art? This Innovative Viewpoints paper introduces the utility of two classes of UAVs for ecohydrologic investigations in two semiarid rangelands of the southwestern U.S. through two useful examples. We discuss the UAV deployments, the derived image, terrain and vegetation products and their usefulness for ecohydrologic studies at two different scales. Within a land-atmosphere interaction study, we utilize high-resolution imagery products from a rotary-wing UAV to characterize an eddy covariance footprint and scale up environmental sensor network observations to match the time-varying sampling area. Subsequently, in a surface and subsurface interaction study within a small watershed, we demonstrate the use of a fixed-wing UAV to characterize the spatial distribution of terrain attributes and vegetation conditions which serve as input to a distributed ecohydrologic model whose predictions compared well with an environmental sensor network. We also point to several challenges in performing ecohydrology with UAVs with the intent of promoting this new self-service (do-it-yourself) model for high-resolution image acquisition over many scales. We believe unmanned aerial vehicles can fundamentally change how ecohydrologic science is conducted and offer ways to merge remote sensing, environmental sensor networks and numerical models.

}, keywords = {ecology, environmental sensor network, hydrology, remote sensing, robotics, scaling, unmanned aircraft systems}, doi = {10.1890/ES14-00217.1}, url = {files/bibliography/JRN00623.pdf}, author = {Enrique Vivoni and A. Rango and C.A. Anderson and Nicole Pierini and A. P. Schreiner-McGraw and Srikanth Saripalli and Andrea S. Laliberte} } @article {49910, title = {Spatial patterns, processes and predictions in ecohydrology: integrating technologies to meet the challenge}, journal = {Ecohydrology}, volume = {5}, year = {2012}, pages = {235-241}, abstract = {

Spatial organization is the pre-eminent challenge of ecohydrology as a geospatial science. Ecohydrological patterns emerge as a result of interactions of fine-scale processes and functions that are difficult to observe, quantify and predict. As a result, an integrated approach to the study of spatial patterns in ecohydrology requires a more focused engagement of sampling, sensing and computational tools that are presently available to the scientific community. Here, an incremental and iterative process is proposed consisting of field experiments sequenced with distributed ecohydrological modelling aimed at identifying emergent spatial patterns. In this commentary, three case studies are presented that illustrate how the integration of spatial technologies can provide new insights into the ecohydrological patterns of arid and semiarid ecosystems. The search for emergent ecohydrological behaviour arising from cross-scale interactions can also yield improved process understanding, predictive capabilities and relevance to societal needs. Copyright {\textcopyright} 2012 John Wiley \& Sons, Ltd.

}, keywords = {cross-scale interactions, North American monsoon, numerical modelling, remote sensig, sensor networks, spatial organization}, doi = {10.1002/eco.1248}, url = {files/bibliography/JRN00604.pdf}, author = {Enrique Vivoni} } @proceedings {50296, title = {Age at puberty in beef heifers: Criollo cattle versus British crossbred cattle}, volume = {59}, year = {2008}, month = {June 24-26, 2008}, pages = {237-240}, address = {Laramie, WY}, abstract = {

Age at puberty is an important factor in estimating the potential productivity of the bovine female. A study was conducted at the ARS-USDA Jornada Experimental Range in 2006 and 2007 to compare onset of puberty, BW, and serum insulin in Criollo and Angus-Hereford crossbred heifers. In 2006, 7 Criollo and 5 crossbred heifers were used to determine length of the estrous cycle and insulin concentrations. Heifers grazed the same pasture during the study with free access to water and mineral supplement. Blood samples were collected twice weekly for both years. In 2007, 15 Criollo and 15 crossbred heifers were used to determine age to puberty (2 or more consecutive progesterone concentrations \> 1 ng/mL), length of the estrous cycle, and insulin concentrations. Initial BW in both 2006 and 2007 crossbred heifers were heavier (P \< 0.01), when compared to Criollo heifers (251.7 and 166.4 \± 12.9 kg; 236.2 and 158.8 \± 4.7 kg, respectively). In 2006, BW gain did not differ (P \< 0.01) between breeds (80.5 and 71.1 \± 4.4 kg for crossbred and Criollo heifers, respectively). In 2007, crossbred heifers gained more BW than Criollo heifers during the study (P \< 0.01; 128.2 and 91.2 \± 4.1 kg, respectively). In 2007, BW at puberty (P \< 0.01) was greater for crossbred heifers than Criollo heifers (323.8 and 213.9 \± 6.6 kg, respectively). However, Criollo heifers tended (P = 0.15) to reach puberty earlier than crossbred heifers (363.5 and 376.7 \± 6.3 d, respectively). Estrous cycle length between crossbred and Criollo heifers in both 2006 and 2007 did not differ (P \> 0.53; 18 and 19 \± 1 d; 18 and 19 \± 1 d, respectively). Serum insulin concentrations were also greater (P \< 0.01), for Criollo compared to crossbred heifers in both 2006 and 2007 (0.67 and 0.54 \± 0.02 ng/mL; 0.68 and 0.58 \± 0.02 ng/mL, respectively). This study suggests that Criollo heifers may reach puberty earlier than British breeds.

}, keywords = {age, Angus-hereford, bovine, Criollo, female, proceedings, productivity}, url = {/files/bibliography/08-058.pdf}, author = {Valverde-Saenz, S.I. and Walsh, J.D. and Gardner, C.M. and Mulliniks, J.T. and Schilling, B.S. and Hallford, D.M. and A L Conzalez and E.L. Fredrickson and Kane, K.K. and Hawkins, D.E.} } @article {50517, title = {The future of vascular plant diversity under four global scenarios}, journal = {Ecology and Society}, volume = {11}, number = {2}, year = {2006}, note = {//Other//LTER-V//entered 08/15/2007}, month = {2006}, pages = {19 pages}, abstract = {

Biodiversity is of crucial importance for ecosystem functioning and human well-being. Using quantitative projections of changes in land use and climate from the four Millennium Ecosystem Assessment (MA) scenarios, we project that reduction of habitat by year 2050 will result in a loss of global vascular plant diversity ranging from 7{\textendash}24\% relative to 1995, after populations have reached equilibrium with the reduced habitat. This range includes both the impact of different scenarios and uncertainty in the SAR relationship. Biomes projected to lose the most species are warm mixed forest, savannahs, shrub, tropical forest, and tropical woodlands. In the 2000{\textendash}2050 period, land-use change contributes more on a global scale to species diversity loss than does climate change, 7{\textendash}13\% vs. 2{\textendash}4\% loss at equilibrium for different scenarios, respectively. However, after 2050, climate change will become increasingly important.

}, keywords = {article, biodiversity scenarios, journal, model,, model, biodiversity scenarios, model, MA, model, Millenium Ecosystem Assessment}, doi = {10.5751/ES-01818-110225 }, url = {files/bibliography/JRN00462.pdf}, author = {Detlef P. Van Vuuren and O. E. Sala and Pereira, Henrique M.} } @article {50515, title = {Rangeland research: strategies for providing sustainability and stewardship to the rangelands of the world}, journal = {Rangelands}, volume = {28}, number = {6}, year = {2006}, month = {December 2006}, pages = {7-14}, abstract = {Rangeland research is an important determinant of how rangelands are and will be used. Although larger external forces such as national and global economies and social and political attitudes have direct impact on uses of rangelands, the methods by which we implement and evaluate those economic and social priorities are based in research and development. Decisions made by rangeland scientists and their institutions today about priorities will have a definite and profound influence on the management of our rangelands in the future. The Society for Range Management, in a once-a-decade symposium, examines the current state of the science, existing technologies and changing social and political trends to identify research needs. In 2005, SRM brought together over 2 dozen speakers and 100 participants to examine new directions in rangeland use and management and propose changes to research that will provide decision-makers at all levels the necessary tools to set goals, implement management and monitor performance.}, keywords = {management, rangelands, sustainability, vegetation}, url = {http://www.srmjournals.org/archive/1551-501X/28/6/pdf/i1551-501X-28-6-7.pdf}, author = {Vavra, J. and Joel R. Brown} } @proceedings {50516, title = {Building a community modeling and information sharing culture}, year = {2006}, month = {July 9-13, 2006}, pages = {Workshop 13}, address = {Burlington, VT}, abstract = {

Free and open exchange of information in research endeavors is beneficial and can lead to much more rapid advances and important discoveries that might otherwise take much longer to achieve. Nevertheless, exchange of information is still restricted by patent law, as well as by institutional, cultural and traditional hurdles that create protective barriers hindering the free flow of this valuable commodity. We believe that one of the greatest challenges we face in creating a new open research paradigm will be building the community modeling and information sharing culture. How do we get engineers and scientists to put aside their traditional modes of doing business that discourage free and open exchange of data and ideas? How do we provide the incentives that will be required to make these changes happen? How do we get our colleagues to see that the benefits of sharing resources far outweigh the costs? We argue that timely sharing of data and information is not only in the best interest of the research community, but that it is also in the best interest of the scientist who is doing the sharing.

}, keywords = {blogs, data sharing, General Public License, idea sharing, information, knowledge sharing, open data, open education, Open source, research}, url = {/files/bibliography/06-075Proc.pdf}, author = {Voinov, A. and Hood, R. and J.D. Daues} } @conference {51056, title = {A portable rainfall simulator for small paired-plot comparisons}, booktitle = {Soil Science Society of America Annual Meeting}, year = {2001}, note = {CD-ROM not available to create pdf file; no pdf number. August 1, 2001}, month = {October 15, 2001}, pages = {CD-ROM}, abstract = {We describe the design and calibration of an inexpensive rainfall simulator in which a manually operated pulley system is used to move a nozzle along a 3m track, uniformly covering an area of up to 1 x 2.5m. Nozzle heights can be set up to 3m from the ground surface. High or low intensity rainfall events can be simulated using a VeeJet and cone nozzle. The simulator, pump and 500-gallon water tank are transported in a pickup truck. Garden hoses transport water from the tank to the simulator, allowing plots to be located in remote sites. Using a VeeJet nozzle, water distribution within 0.5m2 (70.7 x 70.7cm) plots remained uniform in winds up to 40kph, as long as all sides of the simulator were protected with tarps: the average difference between the highest and lowest rates recorded by 5 gauges in each plot was just 11\% of the mean (n = 23 runs). Cone nozzles produced only slightly less uniform distributions. Nearly 80\% and 55\% of drop sizes sfell between 1 and 3mm for the VeeJet and cone nozzle, respectively. We present equilibrium infiltration rates and sediment production data from experiments designed to quantify disturbance effects based on simultaneous measurements from paired plots.}, author = {Justin Van Zee and Jeffrey E. Herrick} } @article {51309, title = {Mutual exclusion by dolichoderine ants on a rich food source}, journal = {Southwestern Naturalist}, volume = {42}, number = {2}, year = {1997}, month = {1997}, pages = {229-231}, abstract = {

Some species of ants recruit rapidly to rich food sources and may exclude other species from that food source (Holldobler and Wilson, 1990). These ant species interfere with other ant species by using chemical repellents or by physical means. For example, the dolichoderine ant Fornelius pruinosus usually displaces the formicine honeypot ants, Myrmecocystus spp., at food baits (Holldobler, 1982). Interference competition should be most intense where densities of ant colonies are high and when food reserves are limited.

}, keywords = {ant colonies, ant species, chemical repellents, food baits, food reserves, food source, formicine, Fornelius pruinosus, honeypot ants, Interference competition, Myrmecocystus spp., physical dolichoderine ant}, url = {/files/bibliography/599.pdf}, author = {Justin Van Zee and Walter G. Whitford and W. E. Smith} } @conference {51308, title = {Responses of Chihuahuan Desert annual plant communities to desertification and exposure to varying grazing stress.}, booktitle = {International Symposium and Workshop Combating Desertification: Connecting Science with Community Action}, year = {1997}, month = {May 12-16, 1997}, pages = {23}, address = {Tucson, AZ}, abstract = {

Ephemeral or annual plant communities respond to a variety of environmental factors, including rainfall, nutrients, temperature, competition, and disturbance. Stressors such as cattle grazing can alter perennial plant communities and soil properties sufficiently to change annual plant communities. We examined density and biomass of annual plant species at sites representing historically documented desertification (a degradation gradient), grazing intensity gradients, grazing exclosures and enclosures, rangeland rehabilitation efforts, and recent fires, as well as sites representing habitats unique to the Chihuahuan Desert. Traditional community vegetation parameters such as species richness and indices of species diversity do not always effectively explain patterns in annual plant communities.\ \  We emphasize examination of key species and micro habitat patterns when analyzing the effects of disturbance of ephemeral plant communities and include examples of how ephemeral plants respond to patchy environments in a wide range of habitats and landscape positions in Chihuahuan Desert rangelands.

}, author = {Justin Van Zee and A.G. de Soyza and Walter G. Whitford} } @article {51310, title = {Soil and sediments: Linkages to new research}, journal = {Bulletin of the Ecological Society of America}, volume = {78}, year = {1997}, note = {//??//LTER-III/}, month = {1997}, pages = {284-285}, abstract = {

Linkages to New Research The Scientific Committee on Problems of the Environment, SCOPE, convened a workshop sponsored by The Ministry of Agriculture, Natural Resources Management and Fisheries of The Netherlands and anonymous donors. The SCOPE Committee on Soil and Sediment Biodiversity and Eco system Functioning, chaired by Diana Wall Freckman, Colorado State Uni versity, USA and aided by co-chairs Margaret Palmer, University of Maryland, USA (Freshwater Sedi ments), Lijbert Brussaard, Agricul tural University, The Netherlands (Soils), and T. Henry Blackburn, Aarhus University, Denmark (Marine Sediments), met for the first work shop in late April 1997 in Wageningen, Holland. The 40 experts from 15 countries, representing tax onomists, ecologists, and biogeo chemists working in the domains of soils, freshwater sediments, and ma rine sediments, spent almost a week summarizing the status of knowledge on biodiversity in relation to func tioning in "their" ecosystems, and identifying similarities in taxa and functions and gaps in knowledge pre venting a synthesis across these do mains. SCOPE was the first integra tive workshop bringing together sci entists from these three domains and the first to emphasize the functional significance of specific organisms and taxa to ecosystem processes and the ecosystem services they represent.

}, keywords = {article, articles, journal, journals, sediment, soil, soil, sediment}, url = {files/bibliography/JRN00251.pdf}, author = {R. A. Virginia and D. W. Freckman} } @article {51548, title = {Soil biota and soil properties associated with surface rooting zone of mesquite (Prosopis glandulosa) in historical and recently desertified Chihuahuan Desert habitats}, journal = {Biology and Fertility of Soils}, volume = {14}, year = {1992}, note = {//NMSU, USDA//LTER II//Listed in LTER3 proposal as citing LTER2 support//}, month = {1992}, pages = {90-98}, abstract = {

The woody legume, mesquite (Prosopis glandulosa) has expanded from its historical habitats (playas and arroyos) to recently occupied grassland and dune habitats during the desertification of perennial grasslands in the Chihuahuan Desert. We studied historical and recently occupied sites, having hypothesized that the trophic structure and population density of soil microarthropods and nematodes associated with the surface root system of mesquite would differ in sites representing historical and recent habitats, and that the N mineralization potential would be lower in the recent habitats. Our results showed that net N mineralization potential did not differ significantly among the sites, even though soil nutrient concentrations and texture varied widely. Concentrations of organic C, N, and P were lowest in the recent dune habitat and highest at the playa. Very low concentrations of P in the dune and grassland soils implicated P as a limiting factor in these systems. The bacterial-feeding and omnivore-predator functional groups made up the largest fraction of the nematode community at most of the sites. The high density of plant-feeding nematodes at the playa indicated that herbivory is potentially most important at this site. Total microarthropod densities did not vary significantly among habitats, with Collembola densities highest in the mesquite dunes. Grazers were the dominant microarthropod functional group. While both C and N pool sizes were higher in the historical habitats, a higher substrate lability in the recent habitats appeared to support biota populations and N mineralization rates equivalent to those in the playa and arroyo. Differences in soil properties and biota among historical and recent mesquite habitats may be important for understanding the changes that have occurred in Chihuahuan Desert ecosystems during desertification.

}, keywords = {article, articles, collembola, community,Prosopis, desertification, journal, journals, microarthropod,Prosopis soils, nematode, nitrogen mineralization, nutrients, nitrogen mineralization, Prosopis, Prosopis, soil biota, Prosopis,rooting zone, Prosopis,soil properties, soil properties}, doi = {10.1007/BF00336256}, url = {files/bibliography/92-Biol\&FertofSoils-Whitford.pdf}, author = {R. A. Virginia and W. M. Jarrell and Walter G. Whitford and D. W. Freckman} } @mastersthesis {51640, title = {Brush control and grazing behavior of goats on semidesert mesquite brush dominated rangeland}, year = {1990}, note = {//??//NONE//}, month = {1990}, pages = {106}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, keywords = {brush control,goats, brush control,Prosopis, dissertation, dissertations, goat,behavior, goat,brush control, Prosopis,brush control, theses, thesis}, author = {Tejada Velez, Einstein Henry} } @mastersthesis {51642, title = {Interception of water by range plants and evaporation from soils in southwest New Mexico}, year = {1990}, note = {//??//NONE//}, month = {1990}, pages = {112}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, keywords = {dissertation, dissertations, evaporation,soils, plants,water interception, theses, thesis, water interception,range plants}, author = {Vera-Cruz, Maria Teresa R. P.} } @proceedings {51643, title = {Desert restoration: the role of woody legumes}, volume = {23-30}, year = {1990}, note = {//OTHER//LTER II//Listed in LTER3 proposal as citing LTER2 support//ProCite field[6]: In}, month = {1990}, publisher = {Island Press}, abstract = {

Recent ecological studies of plant production, nutrient cycling, and water use by legume woodlands in the California Sonoran Desert and the Chihuahuan Desert of New Mexico have provided useful information for restoration efforts in these and in other arid and semiarid regions of the world. Where possible, nitrogen-fixing woody legumes should be included in desert revegetation programs since they enhance soil fertility. Understand and working to duplicate or mimic the natural patterns of moisture and nutrient availability found in these desert woodlands may improve the success rate for their revegetation.

}, keywords = {abstract, abstracts, conference, conference proceedings, conferences, legume, desert restoration, proceeding, proceedings, restoration, legumes}, author = {R. A. Virginia}, editor = {Berger, J. J. (ed.)} } @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} } @book {51692, title = {The use of variation in the natural abundance of 15N to assess symbiotic nitrogen fixation by woody plants}, series = {Stable Isotopes in Ecological Research}, volume = {Ecological Studies}, year = {1989}, note = {//OTHER//LTER II//Listed in LTER3 proposal as citing LTER2 support//ProCite field[6]: InProCite field[24]: Volume 68}, month = {1989}, pages = {375-395}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {New York}, abstract = {

This paper will present selected examples of applications of the natural abundance method to ecological studies. The emphasis will be on results from ongoing ecosystem level studies examining the role of woody legumes in N cycling in warm deserts... Data from other systems (tropical forest, chaparral) where significant sustained inputs of N fixed by woody plants may affect ecosystem processes are also discussed to demonstrate the utility of the natural abundance method in a diversity of systems. The natural 15N abundance approach in an important advancement for the study of deeply rooted plants. Our studies have show that contrary to previous speculation, deeply rooted plants in arid ecosystems can support root symbioses at depths not easily studied using other techniques.

}, keywords = {book, books, chapter, chapters, ecosystem, woody plants, nitrogen fixation, nitrogen fixation, symbiotic, nitrogen isotope, nitrogen, 15N, plant, woody, nitrogen fixation, report, reports, tracer, 15N, woody plants}, url = {files/bibliography/JRN00113.pdf}, author = {R. A. Virginia and W. M. Jarrell and P. Rundel and Shearer, G. and Kohl, D. H.}, editor = {P. Rundel and J. R. Ehleringer and K. A. Nagy} } @book {51800, title = {Approaches for studying the function of deep root systems}, series = {Plant Response to Stress}, number = {Vol. G15}, year = {1987}, note = {//OTHER//NONE//ProCite field[6]: InProCite field[32]: NATO ASI Series}, month = {1987}, pages = {107-127}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Berlin Heidelberg}, abstract = {

The potential importance of deep root systems to plant function has long been recognized. Until recently there have been few attempts to actually quantify the importance of deep roots in securing water and nutrients. The development of new methods and approaches which allow direct and indirect study of deep root function offers new and exciting possibilities. Modern drilling equipment can extract deep soil samples with minimal disturbance to roots and the soil biota. The application of stable isotope techniques using variations in natural abundance is especially exciting since analysis of easily collected aboveground tissues provides information on the function of deep root systems. Information on symbiotic nitrogen fixation and the identification of water sources used by the plant can be obtained with this approach. Although poorly described in natural systems, the structure, species composition and population densities of soil rhizosphere biota may proved information on the relative extent of root activity at a particular soil depth. The application of more than one of these approaches to a single system provides the best opportunity to better understand the functional importance of deep roots to plants.

}, keywords = {biochemistry, deep root systems, book, books, chapter, chapters, fungi, also SEE , mycorrhizal fungi, deep root systems, nematode, deep root systems, nutrients, deep root systems, report, reports, root association, root biomass, root length, root systems, deep, technique, deep root systems, water uptake, deep root systems}, author = {R. A. Virginia and W. M. Jarrell}, editor = {Tenhunen, J. D.} } @proceedings {51857, title = {Pleistocene climates and endemism in the Chihuahuan Desert flora}, year = {1986}, note = { //LOCAL//NONE//ProCite field[6]: In}, month = {October 20-21, 1}, pages = {1-19}, publisher = {Allen Press}, address = {Chihuahuan Desert Research Institute, Sul Ross State University}, abstract = {

Chronological series of radiocarbon dated plant macrofossil assemblages from small geographic areas are providing excellent developmental sequences of vegetation for the last 35,000 years in the northern Chihuahuan Desert. Midden vegetation chronologies have been completed along a latitudinal gradient from the San Andres (33 degrees 11{\textquoteright} N) and Sacramento mountains, New Mexico, and the Jueco Mountains (32 degrees N), and the Rio Grande Village area (29 degrees 30{\textquoteright}N) and Maravillas Canyon ( 29 degrees 33{\textquoteright}N) in the Big Bend of Texas. Although the chronologies demonstrate some differences in composition and the timing of vegetation changes, they agree in a stepwise progression with the most mesic pinyon-juniper-oak vegetation in the Late Wisconsin and the most xeric in the last 4000 years. The Middle Holocene (about 8000-4500 years ago) was apparently very warm with strongly developed summer monsoons and a maximum expansion of grasslands. About 4500 year ago, a creosote-desertscrub corridor between the Chihuahuan and Sonoran deserts was established for the first time since the last interglacial. Deserts are probably at their maximum expansion today with the harshest climates of the present interglacial.

}, keywords = {abstract, abstracts, Chihuahuan Desert, endemic flora, Chihuahuan Desert, paleoclimate, climate,pleistocene, conference, conference proceedings, conferences, ecosystem, pleistocene climates, endemism, flora,succession, packrat middens, pleistocene climates, proceeding, proceedings, succession, Chihuahuan Desert flora, succession,flora}, url = {/files/bibliography/VanDevender_1986_Pleistocene-climates-and-endemism-in-desert-flora.pdf}, author = {T.R. Van Devender}, editor = {Barlow, Jon C. and Michael A. Powell and Timmermann, Barbara N. (eds.)} } @mastersthesis {51858, title = {Variation in diurnal ant species composition and relative abundance on a desert watershed}, year = {1986}, note = {//NMSU//LTER I//}, month = {1986}, pages = {59}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {Variation in ant species composition and relative abundance was studied on a desert watershed 45 km NNE of Las Cruces, New Mexico.... The results of this study suggest that the community structure investigated is the result of individual species{\textquoteright} responses to their physical environment. They also suggest that species response to their physical environment may play a more direct role in structuring communities than modification of competitive relations between species as suggested by the view of desert ant communities structured by interspecific exploitive competition.}, keywords = {ant community, species composition, ant, species composition, community, ant species composition, dissertation, dissertations, insect, ant, theses, thesis}, author = {Steven Scott Van Vactor} } @article {51859, title = {Soil development under legume tree canopies}, journal = {Forest Ecology and Management}, volume = {16}, year = {1986}, note = {//OTHER//NONE//}, month = {1986}, pages = {69-79}, abstract = {Tree legumes influence soil development by altering the physical and chemical properties of the soil beneath the plant canopy. The accumulation of extractable NO3 and PO4 in soil beneath the Sonoran Desert woody legumes Prosopis glandulosa and Dalea spinosa was compared to soil from the tree interspaces. Measurements of natural 15N abundance indicate both these plants symbiotically fix N2 at the sites studied. Nutrient accumulation was related to the water regime of the site. High concentrations of symbiotically fixed N and P as NO3 and PO4 were found in the surface 60 cm of soil beneath a Prosopis stand utilizing groundwater. Relatively little NO3 or PO4 accumulated in the moist soil above the water table at 5 m. In contrast, NO3 and PO4 did not accumulate in the surface soil beneath Dalea growing in a sandy wash. Soil NO3 concentrations were lower beneath Dalea canopies than in the nonvegetated wash. The mechanisms by which tree legumes alter soil properties are reviewed. The direction and potential magnitude of soil changes in managed tree legume systems may be inferred from an understanding of the function of native plant-soil systems.}, keywords = {article, articles, Dalea,soil development, journal, journals, legume tree,soil development, nitrogen,soil, phosphorous,soil, Prosopis,soil development, soil development,legume trees, soil nutrients,nitrogen, soil nutrients,phosphorous}, author = {R. A. Virginia} } @mastersthesis {52251, title = {A comparison between photointerpretation and field vegetation mapping methods on the Jornada Experimental Range}, year = {1975}, note = {//USDA//NONE//}, month = {1975}, pages = {47}, school = {New Mexico State University}, type = {M.S. Thesispp}, address = {Las Cruces, New Mexico}, abstract = {A study was performed with the objective of observing differences between the photointerpretation and the field vegetation mapping procedure.... Differences in detail of delineating vegetation units were also found between the two mapping procedures. The field method showed more generalized mapping while the photointerpretation method showed more detailed mapping of boundaries between vegetation units.}, keywords = {community, vegetation mapping, dissertation, dissertations, mapping, field vegetation mapping, mapping, photointerpretation, photointerpretation, vegetation mapping, technique, photointerpretation, technique,vegetation mapping, theses, thesis, vegetation mapping, methods, vegetation mapping, photointerpretation}, author = {Vasquez-Aldape, Ricardo} } @article {52400, title = {Creosotebush control with phenoxy herbicides, picloram, and fuel oil in southern New Mexico}, year = {1970}, note = {//USDA//NONE//}, month = {1970}, institution = {New Mexico Agricultural Experiment Station}, address = {Las Cruces, New Mexico}, abstract = {Creosotebush was sprayed with various formulations of 2, 4-D and 2,4,5-T, and with picloram and fuel oil, using ground spray equipment, on the University{\textquoteright}s Agricultural Experiment Station ranch, from 1962 to 1966. Results of spraying regrowth of mowed creosotebush at different seasons varied with herbicide used. With 2,4,5-T ester, highest kills were obtained in late summer, and lowest kills were obtained in spring and fall. Early summer results were not significantly different from those of the other seasons. Picloram gave lowest kills in spring, highest kills in fall. The intermediate-level early and late summer kills did not differ significantly from either spring or fall kills. Fuel oil gave lowest kills in spring, highest kills in fall, and intermediate-level kills in early and late summer.}, keywords = {book, books, brush control, herbicide, brush control, Larrea, chapter, chapters, herbicide, "2,4,5-T", herbicide, "2,4-D", herbicide, fuel oil, herbicide, phenoxy, herbicide, picloram, Larrea, herbicide, management, also SEE , report, reports}, isbn = {Bulletin 554}, author = {Valentine, K. A.} } @article {52401, title = {Influence of grazing intensity on improvement of deteriorated black grama range}, year = {1970}, note = {//USDA//NONE//}, month = {1970}, institution = {New Mexico Agricultural Experiment Station}, address = {Las Cruces, New Mexico}, abstract = {The objective of the work reported in this bulletin was to determine the level of use of black grama that will permit satisfactory recovery of deteriorated range.}, keywords = {book, books, Bouteloua, grazing, cattle grazing, Bouteloua, chapter, chapters, grassland, grazing intensity, grassland,productivity, management,Bouteloua, productivity,Bouteloua, report, reports}, isbn = {Bulletin 553}, author = {Valentine, K. A.} } @article {52442, title = {Life-history characteristics of the creosotebush, Larrea tridentata}, year = {1968}, note = {//??//NONE//}, month = {1968}, institution = {New Mexico Agricultural Experiment Station}, address = {Las Cruces, New Mexico}, abstract = {

Creosotebush (Larrea tridentata (DC.) Coville) aggressively invades desert plains grassland in Arizona, New Mexico, and western Texas. Gardner (10) recorded invasion of grassland along the Rio Grande Valley in southern New Mexico and pointed out that it takes the form of frontal advances along the margins of the larger creosotebush communities and of a single plants and then small outlier stands at varying distances from the main bodies of the larger communities. Yang (21) recorded invasions of grassland on upland plains adjacent to the Rio Grande Valley. Buffington and Herbel (2), using 1858 General Land Office survey records and recent observations, reported increase of creosotebush on the Jornada Experimental Range in southern New Mexico from 644 acres of moderately invaded range (creosotebush comprising 15 to 55 percent of the perennial vegetation) in 1858 to 12,388 acres of heavily invaded range (55 to 100 percent of vegetation) in 1963.

}, keywords = {book, books, chapter, chapters, Larrea,life history, report, reports}, isbn = {Bulletin 526}, url = {/files/bibliography/526.pdf}, author = {Valentine, K. A. and J. B. Gerard} } @article {52456, title = {Seasonal suitability, a grazing system for ranges of diverse vegetation types and condition classes}, journal = {Journal of Range Management}, volume = {20}, year = {1967}, note = {//USDA//NONE//}, month = {1967}, pages = {395-397}, abstract = {Seasonal suitability grazing, a grazing system long in use on southwestern range, consists of grazing diverse vegetation types in accord with seasonal use requirements of and benefits to vegetation and livestock. On ranges of diverse vegetation types, it is a superior system with respect to maintenance and improvement of the range, harvest of forage and livestock production.}, keywords = {article, articles, grazing system, seasonal suitability, journal, journals, management, rangeland, seasonal suitability, rangeland, seasonal suitability}, author = {Valentine, K. A.} } @article {52496, title = {A comparative study of soils of selected creosotebush sites in southern New Mexico}, journal = {Journal of Range Management}, volume = {17}, year = {1964}, note = {//USDA//NONE//}, month = {1964}, pages = {23-32}, abstract = {This paper presents the results of a study of physical and chemical properties of soils of four selected creosotebush sites in southern New Mexico. The soils remain capable of supporting establishment and growth of the climax dominant grasses, although deterioration through erosion, and in one case loss of structure, has occurred. One site appeared to have lost soil to the extent that production capacity for the test species had been significantly reduced. At the same site, continuing erosion threatened to further reduce soil productivity by exposure of an underlying high gypsum substratum. Range management practices consisting of proper grazing management and control of creosotebush to preserve and improve these range areas were strongly indicated.}, keywords = {article, articles, biochemistry, Larrea soils, grassland,Larrea, journal, journals, Larrea, biochemistry, Larrea, soils, soil,Larrea}, author = {Valentine, K. A. and Norris, J. J.} } @article {52553, title = {Distance from water as a factor in grazing capacity of rangeland}, journal = {Journal of Forestry}, volume = {45}, year = {1947}, note = {//??//NONE//Journal - short//(New Mexico Agr. Experiment Station Journal Article 44)//}, month = {1947}, pages = {749-754}, abstract = {

An important factor influencing use of range forage is nearness to water supply. The author points out how intensity of grazing use declines with increased distance from water. \ Applying these\  results to a specific pasture made possible a correction ordinary range-carrying capacity estimates to values in accordance with good range use.

}, keywords = {article, articles, grazing management,water, journal, journals, water,grazing management}, url = {/files/bibliography/030.pdf}, author = {Valentine, K. A.} } @article {52552, title = {Effect of Water-Retaining and Water-Spreading Structures in Revegetating Semidesert Range Land}, volume = {341}, number = {341}, year = {1947}, institution = {New Mexico College of A. \& M.A.}, address = {State College, NM}, isbn = {Bulletin 341}, url = {/files/bibliography/044.pdf}, author = {Valentine, K. A.} } @article {52557, title = {Determining the grazing use of grasses by scaling}, journal = {Journal of Forestry}, volume = {44}, year = {1946}, note = {//??//NONE//(New Mexico Agr. Experiment Station Journal Article 39)//}, month = {1946}, pages = {528-529}, keywords = {article, articles, grazing management,scaling method, journal, journals}, author = {Valentine, K. A.} }