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The dataset supports a larger study that examined the impacts of three tackifiers (guar, psyllium, and polyacrylamide) on growth of two dryland mosses (Bryum argenteum and Syntrichia ruralis). Moss fragments were grown in petri dishes and subjected to individual tackifiers in one of three possible concentrations (0.5x, 1x, or 2x) of the respective manufacturer's recommended application rate. Distilled water was used as a control treatment, giving a total of ten treatments (nine tackifier-concentration combinations and a water control). Bryum fragments were watered four times daily for six weeks and Syntrichia fragments were watered twice daily for five weeks, after which the experiments were concluded. Shoot length,...
Salt and sediment contributions to the Colorado River and its tributaries pose economic and environmental concerns for the United States and Mexico. Land use decisions promoting the aggregation of Mancos Shale derived soils are one way to reduce the transportation of salts and sediments to water resources. We used a simple field test of soil aggregate stability to determine the site characteristics influencing the soil stability of sedimentary marine shale in the Gunnison Gorge National Conservation Area in Southwestern Colorado. Ninety-six 1 m2 plots were intensively sampled to explore relationships between soil stability and the biological, chemical and physical site characteristics. Analysis of variance showed...
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The dataset supports a larger study that examined the impacts of three tackifiers (guar, psyllium, and polyacrylamide) on growth of two dryland mosses (Bryum argenteum and Syntrichia ruralis). Moss fragments were grown in petri dishes and subjected to individual tackifiers in one of three possible concentrations (0.5x, 1x, or 2x) of the respective manufacturer's recommended application rate. Distilled water was used as a control treatment, giving a total of ten treatments (nine tackifier-concentration combinations and a water control). Bryum fragments were watered four times daily for six weeks and Syntrichia fragments were watered twice daily for five weeks, after which the experiments were concluded. Shoot length,...
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These data were compiled for a restoration experiment testing the regenerative and functional response of biocrust inoculum reintroduced to a field setting. Regenerative traits measured included measurements of biocrust cover, chlorophyll content, and the roughness of the soil surface. Functional traits measured included nutrient cycling and soil stability. Additionally, these data were compiled for an experiment testing how much soil is lost from different types of ground cover. The data collected was related to ground cover and the amount of soil lost from plots through time. These data were used to inform the conclusions drawn in the accompanying manuscript.
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From 2011-2018 USGS biologists recorded vegetation and biological soil crust (BSC) cover by species and tracked survival of tagged individual plants (388 in total) across 40 locations where paired experimental plots had been installed in 2010. Plant cover was visually estimated using four 75 x 100 cm survey frames. Each site contained a two plots measuring 1.5 by 2.0 meteres: a control plot and a plot covered by a shelter that excluded 35% of incoming precipitation. Plots were selected to represent shallow vs. deep soils, sandstone vs. shale parent material, and dominant plant species on the Colorado Plateau around Moab, Utah. We used an information theoretic approach using generalized linear models to determine...
Molecular methodologies were used to characterize fungal communities associated with lichen-dominated biological soil crusts (BSCs) at two sites on the Colorado Plateau (USA) in order to investigate their diversity and abundance, in relation to that of bacteria, as well as how these parameters corresponded to overall soil crust cover and the presence of anthropogenic disturbance. Fungal community diversity and composition were assessed with denaturing gradient gel electrophoresis (DGGE) fingerprinting of PCR amplified ribosomal genes and by sequencing. Quantitative PCR, specific for fungi as well as bacteria, was used to evaluate relative microbial densities. Two sites with similar soil characteristics, both of...
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* 1 Arid ecosystems are a patch mosaic of plants and biological soil crusts that have been described as islands and mantles of fertility, respectively. To determine whether these patches are metabolically linked by a fungal network of dark septate and arbuscular mycorrhizal fungi (AMF), we measured translocation of nitrogen (N) and carbon (C) in a desert grassland using 15N-NO3 and 13C5, 15N-glutamic acid as substrates. * 2 Substrates were applied as point sources to either small patches of biotic crust or to a subset of leaves within a bunch grass tussock. * 3 Both substrates were translocated over approximately 1 m2 areas (approximately 20 patches) at rates up to 100 cm day?1 during a 4-day period following a...
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The dataset supports a larger study that examined the impacts of three tackifiers (guar, psyllium, and polyacrylamide) on growth of two dryland mosses (Bryum argenteum and Syntrichia ruralis). Moss fragments were grown in petri dishes and subjected to individual tackifiers in one of three possible concentrations (0.5x, 1x, or 2x) of the respective manufacturer's recommended application rate. Distilled water was used as a control treatment, giving a total of ten treatments (nine tackifier-concentration combinations and a water control). Bryum fragments were watered four times daily for six weeks and Syntrichia fragments were watered twice daily for five weeks, after which the experiments were concluded. Shoot length,...
The influence of woody vegetation and biological soil crusts on infiltration capacity is one of the several uncertainties associated with the ecohydrologic effects of woody plant encroachment into arid and semi-arid land systems. The objective of this study was to quantify the effects of Utah juniper (Juniperus osteosperma) and pinyon pine (Pinus edulis) on subcanopy and intercanopy ecohydrologic properties. We measured soil sorptivity, unsaturated hydraulic conductivity [K(h)], soil water content (SWC), and water repellency along radial line transects from under Juniperus and Pinus trees into the centre of the intercanopy space between trees. In the subcanopy, litter mounds, hydrophobic soils, and roots all appear...
Abstract Terminal restriction fragment length polymorphism (TRF or T-RFLP) analysis and 16S rDNA sequence analysis from clone libraries were used to examine cyanobacterial diversity in three types of predominant soil crusts in an arid grassland. Total DNA was extracted from cyanobacteria-, lichen-, or moss-dominated crusts that represent different successional stages in crust development, and which contribute different amounts of carbon and nitrogen into the ecosystem. Cyanobacterial 16S rRNA genes were amplified by PCR using cyanobacteria-specific 16S rDNA primers. Both TRF and clone sequence analyses indicated that the cyanobacterial crust type is dominated by strains of Microcoleus vaginatus, but also contains...
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This raster data depicts the modeled distribution of three grassland states: Biocrust, Grass-bare, and Annualized-bare. We developed models of bare ground, total vegetation, exotic grasses and biological soil crust using spectral data from three year composites of growing season (March-October) Landsat data in Google Earth Engine and field data that were collected over the same period at monitoring sites. The resulting regression models were used to characterize the spatial distribution of putative grassland ecological states across our 251,430 ha study area in and around Canyonlands National Park, UT. This model illustrates how a remote sensing approach to land-cover change can be implemented to guide dryland ecosystem...
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We used the acetylene reduction assay to analyse soil nitrogenase activity at the Jornada Long-Term Ecological Research site (northern Chihuahuan Desert, New Mexico, U.S.A.). A three-day irrigation and fertilization experiment showed that water and carbon (glucose) enhanced nitrogenase activity, while NH4NO3 reduced activity. Micronutrient (Mo, Fe, Co) and phosphorus fertilization had no significant effect. A survey of Jornada Basin soils did not reveal an inverse relationship between nitrogenase activity and the ratio of available nitrogen (N) to phosphorus (P), as hypothesized; however, the highest rates of nitrogenase activity were detected in tarbush floodplain soils with a low ratio of available N to P. These...
This research experimentally examined seasonal effects of fire on biological soil crusts and perennial grasses in shortgrass steppe. We predicted dormant-season fire would have greater negative effects on biological soil crusts than fire during the growing season, but less of an impact on perennial grasses than fire during the growing season. Treatments were dormant- and growing-season fires and unburned reference condition plots. Response variables included biological soil crust and grass percent ground cover, and crust nitrogen fixation and chlorophyll a content. Results indicated shortgrass steppe can recover from fire in three to 30 months, dependent on fire season. Burning during the dormant-season had little...
A portable wind tunnel was used to test the contribution of biological and physical elements to overall soil aggregation on a soil dominated by biological soil crusts in south-eastern Australia. After moderate disturbance and simulated wind erosion, 90% of surface aggregates on the loamy soil and 76% on the sandy soil were dominated by biological elements (cryptogams). Lower levels of biological bonding were observed on the severely disturbed treatment. Linear regression indicated a significant positive relationship (r2=0·72) between biological soil crust cover and dry aggregation levels greater than 0·85mm. To maintain sediment transport below an erosion control target of 5gm−1s−1 for a 65kmh−1 wind at...
The identity of the numerically dominant N(2)-fixing bacteria in biological soil crusts of the Colorado Plateau region and two outlying areas was determined using multiple approaches, to link the environmental diversity of nifH gene sequences to cultured bacterial isolates from the regions. Of the nifH sequence-types detected in soil crusts of the Colorado Plateau, 89% (421/473) were most closely related to nifH signature sequences from cyanobacteria of the order Nostocales. N(2)-fixing cyanobacterial strains were cultured from crusts and their morphotypes, 16S rRNA gene and nifH gene sequences were characterized. The numerically dominant diazotrophs in the Colorado Plateau crusts fell within three clades of heterocystous...
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The dataset supports a larger study that examined the impacts of three tackifiers (guar, psyllium, and polyacrylamide) on growth of two dryland mosses (Bryum argenteum and Syntrichia ruralis). Moss fragments were grown in petri dishes and subjected to individual tackifiers in one of three possible concentrations (0.5x, 1x, or 2x) of the respective manufacturer's recommended application rate. Distilled water was used as a control treatment, giving a total of ten treatments (nine tackifier-concentration combinations and a water control). Bryum fragments were watered four times daily for six weeks and Syntrichia fragments were watered twice daily for five weeks, after which the experiments were concluded. Shoot length,...


    map background search result map search result map Potential environmental controls on nitrogenase activity in biological crusts of the northern Chihuahuan Desert Translocation of nitrogen and carbon integrates biotic crust and grass production in desert grassland Grassland State and Transition Map of Canyonlands National Park Needles District and Indian Creek Grazing Allotment Erosion and Rehabilitation Data, Bandelier National Monument, New Mexico, USA Long-term precipitation reduction experiment in the Colorado Plateau - Survival and mortality data from 2010 to 2018 Tackifier impacts on growth of Great Basin mosses Bryum argenteum and Syntrichia ruralis, a growth chamber study, 2017-2018 Tackifier impacts on growth of Great Basin moss Bryum argenteum, 2017-2018 Tackifier impacts on growth of Great Basin moss Syntrichia ruralis, 2017-2018 Mass adjustment ratios used for Great Basin mosses Bryum argenteum and Syntrichia ruralis, 2017-2018 Tackifier impacts on growth of Great Basin mosses Bryum argenteum and Syntrichia ruralis, a growth chamber study, 2017-2018 Tackifier impacts on growth of Great Basin moss Bryum argenteum, 2017-2018 Tackifier impacts on growth of Great Basin moss Syntrichia ruralis, 2017-2018 Mass adjustment ratios used for Great Basin mosses Bryum argenteum and Syntrichia ruralis, 2017-2018 Erosion and Rehabilitation Data, Bandelier National Monument, New Mexico, USA Translocation of nitrogen and carbon integrates biotic crust and grass production in desert grassland Grassland State and Transition Map of Canyonlands National Park Needles District and Indian Creek Grazing Allotment Potential environmental controls on nitrogenase activity in biological crusts of the northern Chihuahuan Desert Long-term precipitation reduction experiment in the Colorado Plateau - Survival and mortality data from 2010 to 2018