In the United States, three “hot deserts” receive precipitation in the summer months (Mojave, Sonoran, Chihuahuan) and one “cold desert” receives precipitation in the winter (Great Basin).
These ecosystems receive less than 10 in (250 mm) of annual precipitation. Far from desolate, the deserts support high levels of biodiversity including iconic species such as Joshua trees, Mexican free-tailed bats, desert pupfishes, cutthroat trout, pronghorn antelope, desert tortoises, Gila monsters, sage grouse, bighorn sheep, desert iguanas, bristlecone pines, cuckoos, ocotillo, desert poppies, saguaro cactus, kangaroo rats and pigmy rabbits.
Desert biodiversity is the result of evolutionary divergence driven by landscape heterogeneity such as the remote valleys, mountain tops, dry lake beds, sand dunes, and caves across the West. By 12,000 BCE, when the Pleistocene ended, lakes that filled many valleys receded, leaving fishes and other aquatic animals isolated among highly divergent aquatic habitats including lakes with salinities that vary from fresh water to three times the salinity of ocean water. The isolation of populations in terrestrial refugia and desert oases provided the conditions for evolutionary divergence that led to a rich biodiversity.
However, deserts are also impacted by anthropomorphic stressors such as water withdrawal, mining, roads, pollution, over-grazing, energy development, invasive and feral species, and urban sprawl.
Desert Research
Drought & Grazing Experiment: Understanding Impacts and Identifying Mitigation Strategies
River Sediment Dynamics
Well Pad Reclamation and Research
Digital Soil Mapping: New Tools for Modern Land Management Decisions
Long-Term Vegetation Change on the Colorado Plateau
Indicators of Rangeland Health
Conservation of Rare, Sensitive, and At-risk Desert Plant Species
RestoreNet: Distributed Field Trial Network for Dryland Restoration
Colorado Plateau Futures: Understanding Agents of Change on the Colorado Plateau to Facilitate Collaborative Adaptation
Southwest Energy Development and Drought (SWEDD)
A Field Guide to Biological Soil Crusts of Western U.S. Drylands
Ecohydrology and Climate Change in Drylands
- Overview
In the United States, three “hot deserts” receive precipitation in the summer months (Mojave, Sonoran, Chihuahuan) and one “cold desert” receives precipitation in the winter (Great Basin).
These ecosystems receive less than 10 in (250 mm) of annual precipitation. Far from desolate, the deserts support high levels of biodiversity including iconic species such as Joshua trees, Mexican free-tailed bats, desert pupfishes, cutthroat trout, pronghorn antelope, desert tortoises, Gila monsters, sage grouse, bighorn sheep, desert iguanas, bristlecone pines, cuckoos, ocotillo, desert poppies, saguaro cactus, kangaroo rats and pigmy rabbits.
Desert biodiversity is the result of evolutionary divergence driven by landscape heterogeneity such as the remote valleys, mountain tops, dry lake beds, sand dunes, and caves across the West. By 12,000 BCE, when the Pleistocene ended, lakes that filled many valleys receded, leaving fishes and other aquatic animals isolated among highly divergent aquatic habitats including lakes with salinities that vary from fresh water to three times the salinity of ocean water. The isolation of populations in terrestrial refugia and desert oases provided the conditions for evolutionary divergence that led to a rich biodiversity.
However, deserts are also impacted by anthropomorphic stressors such as water withdrawal, mining, roads, pollution, over-grazing, energy development, invasive and feral species, and urban sprawl.
Desert ResearchFilter Total Items: 23Drought & Grazing Experiment: Understanding Impacts and Identifying Mitigation Strategies
Drylands (sometimes called ‘deserts’ or ‘arid and semi-arid' ecosystems) are defined by water scarcity. Understanding how land-use activities may effect dryland ecosystems and dryland ecological processes is a high priority for land conservation and management. Grazing by domestic livestock (typically cattle but also sheep and goats) is the most widespread land-use in drylands globally and a large...River Sediment Dynamics
Sediment controls the physical habitat of river ecosystems. Changes in the amount and areal distribution of different sediment types cause changes in river-channel form and river habitat. The amount and type of sediment suspended in the water column determines water clarity. Understanding sediment transport and the conditions under which sediment is deposited or eroded from the various...Well Pad Reclamation and Research
Reclamation on lands impacted by energy development is complicated and extremely challenging in arid environments due to unstable soils, exotic species, and low and variable precipitation. The reclamation tactics employed by energy operators vary widely and outcomes can differ across plant communities and soil types. In order to address the knowledge gaps regarding how to successfully and...Digital Soil Mapping: New Tools for Modern Land Management Decisions
The field of digital soil mapping has bridged the classic theories of soil science into the modern computing age to produce high resolution predictive soil maps. This body of work utilizes classic soil factorial theory (soil = f[climate, organisms, relief (topography), parent material, time] + ɛ, or ‘clorpt’). The clorpt framework has been approximated using various environmental spatial data...Long-Term Vegetation Change on the Colorado Plateau
The Colorado Plateau, centered around the four corners area of the Southwest, and includes much of Arizona, Utah, Colorado, and New Mexico, is a large and important component of U.S. drylands. This important home to mountains, desert basins, dramatic canyons, and arid woodlands and grasslands is also one of North America’s most rapidly warming hot spots, with rates of warming of up to 2-3° C...Indicators of Rangeland Health
Rangelands are natural ecosystems where the native vegetation consists predominantly of grasses, grass-like plants, forbs, or shrubs. Rangelands include natural grasslands, savannas, shrublands, oak and pinyon-juniper woodlands, many deserts, tundra, alpine communities, marshes, and wet meadows.Conservation of Rare, Sensitive, and At-risk Desert Plant Species
The Mojave Desert is among the hottest and driest of the North American drylands, but in spite of these extreme conditions, and in part because of them, a diverse flora exists. This diversity of rare, endemic, and endangered species is threatened by the complex interaction between fluctuating climate and human-mediated disturbances. USGS studies have identified rare species “hotspots” for planning...RestoreNet: Distributed Field Trial Network for Dryland Restoration
Starting in 2017, U.S. Geological Survey (USGS) researchers and land managers are co-producing a network of restoration field trial sites on Department of Interior (DOI) and surrounding lands in the southwestern U.S. The network systematically tests restoration treatments across a broad range of landscape, soil, and climate conditions. Each site in the network is used to test suitable seed mixes...Colorado Plateau Futures: Understanding Agents of Change on the Colorado Plateau to Facilitate Collaborative Adaptation
The objective of this interdisciplinary research effort is to 1) characterize agents of change important to land management decision makers on the Colorado Plateau; 2) identify and analyze relationships between agents of change and key landscape attributes and processes; 3) collectively assess the influence of agents of change and attributes and processes on the services provided by the ecosystem...Southwest Energy Development and Drought (SWEDD)
Deserts of the southwestern US are replete with oil and gas deposits as well as sites for solar, wind, and geothermal energy production. In the past, many of these resources have been too expensive to develop, but increased demand and new technologies have led to an increase in exploration and development. However, desert ecosystems generally have low resilience to disturbance. More frequent...A Field Guide to Biological Soil Crusts of Western U.S. Drylands
Biological soil crusts (biocrusts) are commonly found on the soil surface in arid and semi-arid ecosystems (collectively called drylands). Biocrusts can consist of mosses, cyanobacteria, lichens, algae, and microfungi, and they strongly interact with the soil. These organisms or consortium of disparate organisms, depending on the specific biocrust, are important to the functioning of ecosystems...Ecohydrology and Climate Change in Drylands
Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. However, climate forecasts in most dryland regions, especially the southwest U.S., call for increasing aridity. Specifically, changing climate will alter soil water availability, which exerts dominant control over ecosystem structure and function in water-limited, dryland ecosystems. This research seeks... - Data
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