Material moved from the overland flow of water resulting from precipitation is collected in
belowground containers to get an estimate of that material entering and exiting the plots.
Water and material collected in a container solely from a rain or wind event is not collected.
Bedload oven-dry weight is obtained and the percent Loss on Ignition is calculated.
This data set is comprised of daily precipitation totals, in inches, measured by Belfort
Instruments weighing rain gauges at 58 locations on the Jornada Experimental Range.
Locations and the dates during which data were collected at them were generally project-oriented.
See comment section (#20) for start and end dates for each location.
Days on which data could not be obtained (due to equipment failure, user error, and/or
other reasons) are flagged as missing within this dataset. As of 31 December 2008 they
comprised 1,270 of the total 291,465 records, which is less than 0.44% of the data set.
This data set consists of soil analyses for nitrate,
ammonium, total nitrogen, moisture content, organic matter, mite
weight, nematode weight and root weight of Erioneuron pulchellum
soil rhizosphere samples taken at monthly intervals from Silva\'s
dissertation research plots. Twenty 6 x 6 m plots were established
with a 3 m buffer between plots. Five plots were randomly
assigned to one of four treatments: (1) chlordane amendment
100ml AI (active ingredients) per 10,000 ml) to exclude
microarthropods, (2) sprinkler irrigation (6 mm per week),
(3) sprinkler irrigation (6 mm/week) plus chlordate amendment (as
above), (4) control (no treatment). Three randomly located
subsamples were taken from each plot.
Mesquite litter mass loss from decomposition associated with soil-litter mixing.
Decomposition models typically under-predict decomposition relative to observed rates in drylands. This discrepancy indicates a significant gap in our mechanistic understanding of carbon and nutrient cycling in these systems. Recent research suggests that certain drivers of decomposition that are often not explicitly incorporated into models (e.g., photodegradation and soil-litter mixing; SLM) may be important in drylands, and their exclusion may, in part, be responsible for model under-predictions. To assess the role of SLM, litterbags were deployed in the Chihuahuan Desert and interrelationships between vegetation structure, SLM, and rates of decomposition were quantified. Vegetation structure was manipulated to simulate losses of grass cover from livestock grazing and shrub encroachment. I hypothesized that reductions in grass cover would promote SLM and accelerate mass loss by improving conditions for microbial decomposition. This study is complete.
For more see: Hewins, D. B., S. R. Archer, G. S. Okin, R. L. McCulley, and H. L. Throop. 2013. Soil-litter mixing accelerates decomposition in a Chihuahuan Desert grassland. Ecosystems 16:183-195
Decomposition models typically under-predict decomposition relative to observed rates in drylands. This discrepancy indicates a significant gap in our mechanistic understanding of carbon and nutrient cycling in these systems. Recent research suggests that certain drivers of decomposition that are often not explicitly incorporated into models (e.g., photodegradation and soil-litter mixing; SLM) may be important in drylands, and their exclusion may, in part, be responsible for model under-predictions. To assess the role of SLM, litterbags were deployed in the Chihuahuan Desert and interrelationships between vegetation structure, SLM, and rates of decomposition were quantified. Vegetation structure was manipulated to simulate losses of grass cover from livestock grazing and shrub encroachment.
We hypothesized that (i) reductions in grass cover would destabilize soils and promote SLM, and (ii) that SLM would enhance microbial abundance and alter microbial community composition in ways that accelerate decomposition. To test our hypotheses, we quantified mass loss, and chemistry of litter incubated on sites with experimental reductions in grass cover (0 to 100% removals) over a 12-month period. This dataset includes data pertaining to the percent carbon, percent nitrogen, and the carbon to nitrogen ratio. This study is complete.
The goal of this sampling effort is to describe the vegetation response to treatments. Data were collected following the line-point intercept method (Herrick et al. 2009). Although the original LPI data set was in multivariate form with separate columns for canopy layers and soil surface, this data set has been transposed into vertical form, implementing a “layer” variable, so that all species and soil surface codes appear in one column. Within each exclosure, 4837 points were sampled with the following exceptions:
Dataset consists of horizontal dust flux at multiple heights from BSNE dust collectors located in treatment plots (different percent vegetation removed) and adjacent downwind effect plots. Year 2008 was an annual collection. Collection in subsequent years occurred before and after the wind season. The experiment was designed to test the effects of increasing wind erosion on soil and vegetation properties at the Jornada. In order to increase wind erosion rates, vegetation was removed to increase bare surface area and stimulate erosion (the less vegetation present the greater the wind erosion). The basic experimental design includes three treatment blocks. Each block has four treatment plots with different level of vegetation removed (25-100%) and a control treatment. Treatment plots are 25x50m with 25m buffers between. The vegetation removal includes grasses and small shrubs (like XASA and ZIGR), but not mesquite or yucca or any of the larger shrubs). Also, adjacent downwind plots are included in the design. These plots are strictly for monitoring of soil and vegetation properties, so no maintenance is required on these areas.
