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 proportion of dryland residents can be characterized as subsistence agropastoralists. Improper grazing in drylands, particularly during drought, can negatively impact plant productivity, soil erosion, water capture, and downstream water quantity and quality. Of particular concern is potentially irreversible ecosystem changes brought about by these scenarios.
Long-term Vegetation Change on the Colorado Plateau
The USGS & National Park Service scientists have been monitoring grasslands across a historic grazing gradient in Canyonlands National Park sites since 1996, including a grassland that has never been grazed by domestic livestock.
Chronic Drought Impacts on Colorado Plateau Ecosystems
Warming and associated drying will have large effects on dryland plants & soils. In this long-term study (2010-present), we are examining the effects of moderate, but long-term chronic drought using a network of 40 experimental drought shelters.
Colorado Plateau Extreme Drought in Grassland Experiment
In drylands, short-term extreme droughts can have profound ecosystem effects. In this study, we are examining the impacts of extreme seasonal drought on grassland communities of the Colorado Plateau & recovery from drought.
Grazing by large domestic herbivores effects dryland ecosystems directly through selective removal of plant biomass and physical disturbance (hoof impact) and indirectly via feedbacks through altering plant composition, plant-soil feedbacks, and other processes. Importantly, the direct effects of grazing—especially during drought—on plants and soils can disrupt or alter dryland ecosystem processes and result in profound, often irreversible, changes. These concerns are especially great given the increased risk of multi-year droughts brought on by climate change, the high vulnerability of important forage species to warming environments, and the demonstrated low resilience of many sensitive dryland ecosystems to the combined impacts of grazing and drought.
In this study, we are conducting experiments to shed light on how drought, disturbance, and grazing by domestic livestock interact. In addition, we are testing if changes in grazing timing may reduce risk to rangelands during and following drought. In this new experiment, we are looking at how drought and grazing act separately and in combination to influence the structure and function of dryland ecosystems.
Below are other science projects associated with this project.
Drylands are highly vulnerable to climate and land use changes: what ecosystem changes are in store?
Wind Erosion and Dust Emissions on the Colorado Plateau
Long-Term Vegetation Change on the Colorado Plateau
Chronic Drought Impacts on Colorado Plateau ecosystems (Rain-Out Experiment)
Colorado Plateau Extreme Drought in Grassland Experiment (EDGE)
- Overview
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 proportion of dryland residents can be characterized as subsistence agropastoralists. Improper grazing in drylands, particularly during drought, can negatively impact plant productivity, soil erosion, water capture, and downstream water quantity and quality. Of particular concern is potentially irreversible ecosystem changes brought about by these scenarios.
Long-term Vegetation Change on the Colorado Plateau
The USGS & National Park Service scientists have been monitoring grasslands across a historic grazing gradient in Canyonlands National Park sites since 1996, including a grassland that has never been grazed by domestic livestock.
Chronic Drought Impacts on Colorado Plateau Ecosystems
Warming and associated drying will have large effects on dryland plants & soils. In this long-term study (2010-present), we are examining the effects of moderate, but long-term chronic drought using a network of 40 experimental drought shelters.
Colorado Plateau Extreme Drought in Grassland Experiment
In drylands, short-term extreme droughts can have profound ecosystem effects. In this study, we are examining the impacts of extreme seasonal drought on grassland communities of the Colorado Plateau & recovery from drought.
Grazing by large domestic herbivores effects dryland ecosystems directly through selective removal of plant biomass and physical disturbance (hoof impact) and indirectly via feedbacks through altering plant composition, plant-soil feedbacks, and other processes. Importantly, the direct effects of grazing—especially during drought—on plants and soils can disrupt or alter dryland ecosystem processes and result in profound, often irreversible, changes. These concerns are especially great given the increased risk of multi-year droughts brought on by climate change, the high vulnerability of important forage species to warming environments, and the demonstrated low resilience of many sensitive dryland ecosystems to the combined impacts of grazing and drought.
In this study, we are conducting experiments to shed light on how drought, disturbance, and grazing by domestic livestock interact. In addition, we are testing if changes in grazing timing may reduce risk to rangelands during and following drought. In this new experiment, we are looking at how drought and grazing act separately and in combination to influence the structure and function of dryland ecosystems.
Sources/Usage: Public Domain.Example of the passive rainfall reduction shelters used to create experimental drought near Canyonlands National Park, Utah (April 2015) - Science
Below are other science projects associated with this project.
Drylands are highly vulnerable to climate and land use changes: what ecosystem changes are in store?
Improper land use during drought has been a major driver of land degradation in drylands globally, especially in the western U.S. Increasing aridity in western U.S. drylands under future climates will exacerbate risks associated with drought and land use decisions. This project provides critical observational, experimental, and modelling evidence to support our DOI partners with decision processes...Wind Erosion and Dust Emissions on the Colorado Plateau
Wind erosion of soils and dust emissions are a significant resource management challenge on the Colorado Plateau. Loss of topsoil and associated aeolian sediment (wind-driven sediment) movement can lead to reduced soil fertility as well as abrasion and burial of vegetation. Dust in the atmosphere poses a threat to human health, visual resources, and regional water supplies (due to interactions...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, 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 within...Chronic Drought Impacts on Colorado Plateau ecosystems (Rain-Out Experiment)
In drylands, chronic reductions in water availability (press-drought) through reduced precipitation and increased temperatures may have profound ecosystem effects, depending on the sensitivities of the dominant plants and plant functional types. In this study, we are examining the impacts of moderate, but long-term chronic drought using a network of 40 drought shelters on the Colorado Plateau...Colorado Plateau Extreme Drought in Grassland Experiment (EDGE)
In drylands, short-term extreme droughts can have profound ecosystem effects, depending on the timing (seasonality) of drought and the sensitivities of the dominant plants and plant functional types. Past work suggests that cool season drought may disproportionately impact regionally important grass and shrub species. In this study, we are examining the impacts of extreme seasonal drought on... - Partners