completed

Data set status is completed, indicating that data is no longer being collected

Dataset: 

Study number: 

86

Data set ID: 

210086009

Abstract: 

The purpose of this study is to determine whether or not the activities of small mammals regulate plant community structure, plant species diversity, and spatial vegetation patterns in Chihuahuan Desert shrublands and grasslands. What role if any do indigenous small mammal consumers have in maintaining desertified landscapes in the Chihuahuan Desert? Additionally, how do the effects of small mammals interact with changing climate to affect vegetation patterns over time? This study will provide long-term experimental tests of the roles of consumers on ecosystem pattern and process across a latitudinal climate gradient. The following questions or hypotheses will be addressed. 1) Do small mammals influence patterns of plant species composition and diversity, vegetation structure, and spatial patterns of vegetation canopy cover and biomass in Chihuahuan Desert shrublands and grasslands? Are small mammals keystone species that determine plant species composition and physiognomy of Chihuahuan Desert communities as Brown and Heske (1990a) and Gibbens et al. (1993) suggest? Do small mammals have a significant role in maintaining the existence of shrub islands and spatial heterogeneity of creosotebush shrub communities? 2) Do small mammals affect the taxonomic composition and spatial pattern of vegetation similarly or differently in grassland communities as compared to shrub communities? How do patterns compare between grassland and shrubland sites, and how do these relatively small scale patterns relate to overall landscape vegetation patterns? 3) Do small mammals interact with short-term (annual) and long-term (decades) climate change to affect temporal changes in vegetation spatial patterns and species composition? Data collected for each captured rodent: habitat, trap night, trap web, recapture, species, sex, age, weight, reproductive status, reproductive condition.

Data sources: 

data_JornadaStudy_086_smes_rodent_trapping

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394009

Abstract: 

Soils were sampled under Prosopis at four sites and under Larrea at one site on the Jornada Desert Site on October 1, 1986. Samples were taken from two depths (0-15cm, 15-30cm) for three canopy positions and one interzone position for each tree or shrub. Four trees or shrubs were sampled at each site. The soils were analyzed for Total Kjeldahl Nitrogen (TKN), and inorganic N-- nitrate-N and ammonium-N.

Data sources: 

data_JornadaStudy_394_mesquite_surface_soil_canopy_position_nutrient

LTER Core Area(s): 

Dataset: 

Study number: 

29

Data set ID: 

210029001

Abstract: 

Plant nutrient distribution beneath and between plant canopies in the Mesquite, Grassland, Playa, Creosotebush, and Tarbush plant communities. The LTER plant biomass plots were harvested during spring, fall, 1989 and winter 1990, in 5 vegetation zones (Mesquite, Grassland, Playa, Creosotebush, Tarbush), 3 sites per zone (site with low, medium, and high biomass, ranked based on fall-89 biomass). Samples were analyzed for total Kjeldahl N, and total phosphorus. Site ranking based on Fall 1989 biomass estimates: ZONE SITES BIOMASS (using FALL-89 rank of plant) M RABB low M NORT medium M WELL high G IBPE low G SUMM medium G BASN high P TABO low P COLL medium P SMAL high C CALI low C GRAV medium C SAND high T WEST low T TAYL medium T EAST high

Data sources: 

data_Jornada_029001_npp_plant_nutrient_distribution

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394001

Abstract: 

**We addressed the question, are microarthropod assemblages present in soils throughout the rhizosphere of a deep-rooted desert plant? If microarthropods are present, what is the taxonomic and functional structure of that assemblage? The presence of a generalist microarthropod assemblage would suggest functional relationships among deep soil biota similar to the relationships documented in shallow soils. Data set consists of microarthropods and microarthropod numbers found at different soil depths associated with four mesquite ecosystems (playa, coppice dune, arroyo, and grassland).

Data sources: 

data_JornadaStudy_394_mesquite_deep_soil_microarthropod

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394002

Abstract: 

Soil cores were collected under mesquite (Prosopis glandulosa) trees at playa, wash, sand dune, and grassland sites on the Jornada LTER site to depths of 15, 9, 7, and 4 m. Soil cores (to 4 m) were also taken under creosote bush (Larrea tridentata) near the wash site. Soils were extracted and analyzed for micronutrients, Zn, Cu, Fe, and Mn.

Data sources: 

data_JornadaStudy_394_mesquite_deep_soil_micronutrient

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394003

Abstract: 

Soil cores collected under mesquite (Prosopis glandulosa) trees at several sites and under Larrea at one site at the Jornada LTER were incubated to determine the N-mineralization potential.

Data sources: 

data_JornadaStudy_394_mesquite_deep_soil_n_mineralization

LTER Core Area(s): 

Dataset: 

Study number: 

4

Data set ID: 

210394004

Abstract: 

*We have hypothesized that large rhizobial population densities can occur at considerable depths in woody legume systems where deep moisture also occurs. However, associated with deep soil environments are low concentrations of soil nutrients that might affect nodulation and also limit survival of free-living rhizobia. The objectives of this study were to (1) determine if results from a previous study of a mesquite woodland utilizing groundwater in the Californian Sonoran desert were generizable to mesquite systems in other deserts where root depth varied with ecosystem type and (2) examine possible relationships of soil properties and host-plant phenology to rhizobial concentrations. Data set contains total nitrogen, total phosphorous,NH4-N, NO3-N, PO4-P, percent moisture, total roots, tap roots, fine roots, vesicular arbuscular mycorrhiza, rhizobia Most Probable Number, and Rhizobia log (1+MPN).

Data sources: 

data_JornadaStudy_394_mesquite_deep_soil_nutrients

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394005

Abstract: 

*We have hypothesized that large rhizobial population densities can occur at considerable depths in woody legume systems where deep moisture also occurs. However, associated with deep soil environments are low concentrations of soil nutrients that might affect nodulation and also limit survival of free-living rhizobia. The objectives of this study were to (1) determine if results from a previous study of a mesquite woodland utilizing groundwater in the Californian Sonoran desert were generizable to mesquite systems in other deserts where root depth varied with ecosystem type and (2) examine possible relationships of soil properties and host-plant phenology to rhizobial concentrations. Data set contains analyses for SO4, sodium, calcium, manganese, sodium-absorption-ration, total cations, electrical conductivity, pH, saturation percentage, total carbon, inorganic carbon, organic carbon, and gravimetric soil moisture.

Data sources: 

data_JornadaStudy_394_mesquite_deep_soil _saturation_extract

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394006

Abstract: 

**The objective of the present research was to determine whether there have been changes in the structure and function of the surface (0-20cm) soil system, the zone most affected by litter decomposition, which is associated with the rapid movement of mesquite from historical habitats (arroyo and playa fringe) into recent habitats (grassland and dunes). We hypothesized that the soil biotic communities would be poorly developed in the recent mesquite habitats because of lower soil C and nutrient concentrations. Data set contains microarthropod code, order, family, total number of mites, and trophic group for microarthropods sampled at two depth ranges in the top 20 cm of soil.

Data sources: 

data_JornadaStudy_394_mesquite_surface_soil_microarthropod

LTER Core Area(s): 

Dataset: 

Study number: 

394

Data set ID: 

210394007

Abstract: 

**The objective of the present research was to determine whether there have been changes in the structure and function of the surface (0-20cm) soil system, the zone most affected by litter decomposition, which is associated with the rapid movement of mesquite from historical habitats (arroyo and playa fringe) into recent habitats (grassland and dunes). We hypothesized that the soil biotic communities would be poorly developed in the recent mesquite habitats because of lower soil C and nutrient concentrations. Data set contains Baerman Funnel extracted nematodes (fungal feeders, bacterial feeders, omnivore-predator, total plant parasites, total nematodes) and Elutriator extracted nematodes (fungal feeders, bacterial feeders, omnivore-predator, total plant parasites, total nematodes).

Data sources: 

data_JornadaStudy_394_mesquite_surface_soil _nematode

LTER Core Area(s): 

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