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This dataset provides location information and some limited attributes of known and potential ciénegas in the Madrean Archipelago ecoregion and closely surrounding area. This was created using point data and information provided by Dean Hendrickson and Thomas Minckley, combined with potential locations derived from analysis of classified raster land cover images and other specialized datasets. Ciénegas, as defined here, are wetlands in arid and semi-arid regions associated with groundwater or lotic components that ideally result in perennial waters on temporal scales of decades to centuries. Ciénegas are typically located at elevations ranging from 0 to 2000m. Ciénegas are typified by significant differences in...
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This project identifies priority areas in the Columbia Plateau Ecoregion to implement conservation strategies for riverine and riparian habitat. This is tailored towards the Arid Lands Initiative (ALI) conservation goals and objectives, and provides the foundation for adaptation to a changing climate. This project adopts a “zoned” approach to identifying focal areas, connectivity management zones and zones for riparian habitat and ecological representation. Through a series of workshops and webinars, the ALI articulated its freshwater conservation goals and targets. Key aspects of these goals included: a focus on non-anadromous salmonid (salmon and steelhead) species, include riparian birds and waterfowl as key...
Recent research suggests that micronutrients such as Mn may limit growth of slow-growing biological soil crusts (BSCs) in some of the drylands of the world. These soil surface communities contribute strongly to arid ecosystem function and are easily degraded, creating a need for new restoration tools. The possibility that Mn fertilization could be used as a restoration tool for BSCs has not been tested previously. We used microcosms in a controlled greenhouse setting to investigate the hypothesis that Mn may limit photosynthesis and consequently growth in Collema tenax, a dominant N-fixing lichen found in BSCs worldwide. We found no evidence to support our hypothesis; furthermore, addition of other nutrients (primarily...
The definition of desertification accepted in the ad hoc conference held by UNEP in Nairobi in 1977 and confirmed at the Earth Summit on Environment and Development held in Rio de Janeiro in 1992 is: ?arid, semi-arid and dry-subhumid land degradation?. There is no global long-term trend in any rainfall change over the period of instrumental record (c. 150 years), but there has been an increase of 0�5�C in global temperature over the past 100 years. This increase seems partly due to urbanization, as there is no evidence of it resulting from atmospheric pollution by CO2and other warming gases (SO2, NO2, CH4, CFH etc.). On the other hand, the thermal increase is uneven, increasing with latitudes above 40� N and S....
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Biological soil crusts, a community of cyanobacteria, lichens, and mosses that live on the soil surface, occur in deserts throughout the world. They are a critical component of desert ecosystems, as they are important contributors to soil fertility and stability. Future climate scenarios predict alteration of the timing and amount of precipitation in desert environments. Because biological soil crust organisms are only metabolically active when wet, and as soil surfaces dry quickly in deserts during late spring, summer, and early fall, the amount and timing of precipitation is likely to have significant impacts on the physiological functioning of these communities. Using the three dominant soil crust types found...
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Soil gas methane and combustible gas concentrations collected from oil and gas well pad locations in Utah. Soil gas samples were measured on site and/or collected for later analysis as described in supporting documentation. Multiple sample locations around well head and depths within the soil profile are available for select sites. Supporting documents provide information of sample collection protocol and data quality assurance.
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Big Flat, Big Indian North, Big Indian South, Big Valley, Bluebell, All tags...
Microbiotic crusts are biological soil crusts composed of lichens, cyanobacteria, algae, mosses, and fungi. The biodiversity of these crusts is poorly understood; several cosmopolitan species dominate in most areas, but many species are confined to one or a few sites. Nitrogen fixation by organisms within the crust can be the dominant source of nitrogen input into many ecosystems, although rates of nitrogen input are limited by water availability, temperature, and nitrogen loss from the crust. Photosynthetic rates of the microbiotic crust can be 50% of those observed for higher plants, but the contribution of crusts to carbon cycling is not known. The microbiotic crust binds soil particles together, and this significantly...
Microbiotic crusts are biological soil crusts composed of lichens, cyanobacteria, algae, mosses, and fungi. The biodiversity of these crusts is poorly understood; several cosmopolitan species dominate in most areas, but many species are confined to one or a few sites. Nitrogen fixation by organisms within the crust can be the dominant source of nitrogen input into many ecosystems, although rates of nitrogen input are limited by water availability, temperature, and nitrogen loss from the crust. Photosynthetic rates of the microbiotic crust can be 50% of those observed for higher plants, but the contribution of crusts to carbon cycling is not known. The microbiotic crust binds soil particles together, and this significantly...
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Biological soil crusts (BSCs) are an integral part of dryland ecosystems and often included in long-term ecological monitoring programs. Estimating moss and lichen cover is fairly easy and non-destructive, but documenting cyanobacterial level of development (LOD) is more difficult. It requires sample collection for laboratory analysis, which causes soil surface disturbance. Assessing soil surface stability also requires surface disturbance. Here we present a visual technique to assess cyanobacterial LOD and soil surface stability. We define six development levels of cyanobacterially dominated soils based on soil surface darkness. We sampled chlorophyll a concentrations (the most common way of assessing cyanobacterial...
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Biological soil crusts are an essential part of desert ecosystems throughout the world, as they are important in soil stabilization and soil fertility. Despite their importance, there have been few efforts to examine the population dynamics of the dominant species comprising these crusts or the effect of exotic plant invasions on these dynamics. In this study, we followed changes in lichen and moss cover for 8 years in plots dominated by native grasses or invaded by the exotic annual grass Bromus tectorum and across sites representing a range of land use histories. Our data showed that cover of both lichens and mosses can increase dramatically over short time periods, often going from just above 0% cover to as high...
Biological soil crusts (BSCs) are ubiquitous lichen?bryophyte microbial communities, which are critical structural and functional components of many ecosystems. However, BSCs are rarely addressed in the restoration literature. The purposes of this review were to examine the ecological roles BSCs play in succession models, the backbone of restoration theory, and to discuss the practical aspects of rehabilitating BSCs to disturbed ecosystems. Most evidence indicates that BSCs facilitate succession to later seres, suggesting that assisted recovery of BSCs could speed up succession. Because BSCs are ecosystem engineers in high abiotic stress systems, loss of BSCs may be synonymous with crossing degradation thresholds....
Soil surface growths dominated by cyanobacteria and the lichen Collema in southeastern Utah are shown to be associated with greater tissue content of several bio-essential elements in two co-occurring seed plants (Festuca octoflora, Poaceae, and Mentzelia multiflora, Loasaceae). The elements N, P, K, Ca, Mg, and Fe were present in significantly greater concentrations in Festuca growing on soils heavily encrusted with cyanobacteria and cyanolichens than in plants on the same soil where foot traffic had destroyed the cryptobiotic crusts. With Mentzelia, N, Mg, and Fe were present in significantly greater concentrations in plants from sites with encrusted soil surfaces than on blow-sand sites. The cryptobiota appeared...
This dataset contains vegetation data collected at a variety of watershed restoration sites across southeastern Arizona over 5 years. The semiarid habitats in the Madrean Archipelago Ecoregion, which extends from southern Arizona into northern Mexico, are facing many challenges from climate change to land use change which threaten the ecological and cultural values of the region. Watershed restoration practitioners use a variety of techniques such as gabions, check dams, and cross vanes to reduce the effects of these threats and improve or maintain watershed function. Since vegetation dynamics in the area are driven by water availability, these restoration techniques appear to have secondary effects on the vegetation...
Biological soil crusts are an important component of desert ecosystems, as they influence soil stability and fertility. This study examined and compared the short-term vehicular impacts on lichen cover and nitrogenase activity (NA) of biological soil crusts. Experimental disturbance was applied to different types of soil in regions throughout the western U.S. (Great Basin, Colorado Plateau, Sonoran, Chihuahuan, and Mojave deserts). Results show that pre-disturbance cover of soil lichens is significantly correlated with the silt content of soils, and negatively correlated with sand and clay. While disturbance appeared to reduce NA at all sites, differences were statistically significant at only 12 of the 26 sites....
Biological soil crusts (BSC) are a dominant feature in arid and semi-arid ecosystems. BSC stabilize soils, contribute nitrogen and carbon, enhance vascular plant nutrition, and influence local hydrologic cycles. However, these ecological roles are determined by the species composition, morphology, and physiological functioning of the BSC. These factors, in turn, can be strongly affected by land use, invasive plants, and climate change. Soil surface disturbance and/or dominance by invasive plants both result in loss of lichens and mosses, leaving cyanobacteria dominating the soil surface. This loss reduces soil stability, carbon and nitrogen contributions, surface temperatures, and soil water retention times. Climate...
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The Central Mojave Special Features shapefile provides point locations for known or potential places where vegetation alliances or unique stands occurred (from 1997-1999) with less than 5 hectares of spatial extent. These designations were provided separately from the Mojave Vegetation Polygons because the target standard for the polygons was a minimum mapping unit (MMU) of 5 hectares, thus methods used at the time to assign labels precluded mapping these special features as polygons. The special features points are still included because it is important to note the known or potential location of vegetation alliances for future mapping at finer spatial resolution. The metadata record (Mojave-Vegetation-Mapping_Special-Features-Points-Metadata.xml)...
Understanding the timing of mountain building and desert formation events in western North America is crucial to understanding the evolutionary history of the diverse arid-adapted biota that is found there. While many different, often conflicting descriptions exist regarding geobiotic change in western North America, little work has been done to synthesize these various viewpoints. In this paper we present several case studies that illustrate the differences in the various explanations, based on geological and paleobiological data, detailing mountain uplift and desertification in western North America. The majority of the descriptions detailing mountain building in this area fall into two major periods of uplift,...
Biological soil crusts of arid and semiarid lands contribute significantly to ecosystem stability by means of soil stabilization, nitrogen fixation, and improved growth and establishment of vascular plant species. In this study, we examined growth and nutrient content of Bromus tectorum, Elymus elymoides, Gaillardia pulchella, and Sphaeralcea munroana grown in soil amended with one of three levels of biological soil crust material: (1) a low-fertility sand collected near Moab, Utah; (2) sand amended with a 1-cm top layer of excised soil crust; and (3) crushed crust material. In addition, all plants were inoculated with spores of the arbuscular mycorrhizal fungus, Glomus intraradices. Plants were harvested after...
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Ciénegas, as defined here, are wetlands in arid and semi-arid regions associated with groundwater or lotic components that ideally result in perennial waters on temporal scales of decades to centuries. Ciénegas are typically no lower than 0 m, and higher than 2000 m, rarely lower but sometimes higher elevation localities occur. Ciénegas are typified by significant differences in flora and fauna relative to the greater terrestrial conditions in the region in which it is located. Ciénegas are freshwater to brackish North American wetlands associated with fluvial systems of arid/semi-arid areas of the southwestern U.S. and northwestern Mexico. Once extensively utilized by the region's indigenous human cultures, early...
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The Central Mojave Vegetation Polygons shapefile represents areas of the Mojave Desert classified into vegetation classes or alliances representative of the area from 1997-1999. The classification of these areas were derived from context gathered in the field data, photographs and additional satellite imagery that is not included in this data release. The original map coverage was preserved and released as a shapefile (mojave_veg_polygons.shp). In contrast to the Special Features Points vegetation classifications (described in the Special Features Points shapefile metadata record and ScienceBase item), the Central Mojave Vegetation Polygons were designated by vegetation alliances that extended 5 hectares or more....
map background search result map search result map Visually assessing the level of development and soil surface stability of cyanobacterially dominated biological soil crusts Soil lichen and moss cover and species richness can be highly dynamic: The effects of invasion by the annual exotic grass Bromus tectorum, precipitation, and temperature on biological soil crusts in SE Utah Response of desert biological soil crusts to alterations in precipitation frequency. Selection frequency score Figure(6) Soil Methane and Combustible Gas Concentrations from Oil-Gas Well Pads in Utah, U.S.A. Central Mojave Desert Vegetation Mapping Project, California, 1997-1999: Mojave Vegetation Polygons Central Mojave Desert Vegetation Mapping Project, California, 1997-1999: Special Features Points Short Term Vegetation Response Study at Watershed Restoration Structures in Southeastern Arizona, 2015 - 2019 Database of Ciénega Locations in Southwestern United States and Northern Mexico Spatial Database of Known and Potential Ciénegas in the Greater Madrean Archipelago Ecoregion Soil lichen and moss cover and species richness can be highly dynamic: The effects of invasion by the annual exotic grass Bromus tectorum, precipitation, and temperature on biological soil crusts in SE Utah Response of desert biological soil crusts to alterations in precipitation frequency. Visually assessing the level of development and soil surface stability of cyanobacterially dominated biological soil crusts Short Term Vegetation Response Study at Watershed Restoration Structures in Southeastern Arizona, 2015 - 2019 Spatial Database of Known and Potential Ciénegas in the Greater Madrean Archipelago Ecoregion Central Mojave Desert Vegetation Mapping Project, California, 1997-1999: Mojave Vegetation Polygons Central Mojave Desert Vegetation Mapping Project, California, 1997-1999: Special Features Points Soil Methane and Combustible Gas Concentrations from Oil-Gas Well Pads in Utah, U.S.A. Selection frequency score Figure(6) Database of Ciénega Locations in Southwestern United States and Northern Mexico