Wind Erosion and Dust Emissions on the Colorado Plateau Active
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 with mountain snowpack). Erosion of surface soils and subsequent emissions of dust are greatly influenced by land-use practices and climate, especially drought. In this project, the U.S. Geological Survey and collaborators are monitoring aeolian sediment movement, atmospheric dust concentrations, and related erosion and dust properties to better understand the relationship between land use (grazing by domestic livestock, unpaved roads, off highway vehicles, and oil and gas development), climate variability, and aeolian processes. Results show that dust emissions increase during drought, but these increases in erosion processes are exacerbated with common land use types, especially off-road vehicle activity.
Background & Importance
The American Dust Bowl of the 1930s produced hard-learned lessons about how misguided land use and climate variation can trigger extreme wind erosion and land degradation. During the Dust Bowl, plowing in semi-arid regions coincident with drought caused extreme wind erosion and general economic devastation. Although many lessons were learned from the Dust Bowl, we now face similar challenges but with much more varied land use demands, a larger population base, and risks of intensifying drought. Although considerable uncertainty exists, current land use and drought trends have the potential to cause destabilization of sediments that increases wind erosion, sand dune mobilization, sand storms, dust emissions, productivity loss, and desertification.
The processes controlling wind erosion and dust emissions operate at scales ranging from microns to global. Vegetation height, orientation and size of vegetation gaps, soil type, soil cover, surface roughness, wind speed, and antecedent moisture all can influence dust dynamics. The Colorado Plateau in the southwestern United States is an active aeolian system that has co-occurring land-use types which vary at fine scales over a large area, each with the potential to generate large quantities of dust due to soil surface disturbance. Land uses of concern include energy and mineral extraction, unpaved road and trail development, and livestock grazing. Many of the regional shale formations (e.g. Mancos, Chinle, and Morrison Formations) have a variety of metals and other potentially hazardous constituents that could be mobilized as dust. Although this region is only a minor contributor to global dust loads currently, it represents one area of many semi-arid regions in the world that, if destabilized by drought and land use, could become a much larger dust source. The general objective of this work is to understand how land use and climate separately and synergistically affect wind erosion and dust emissions on the Colorado Plateau.
General Methods
We are employing a variety of measurement approaches to understand the controls on dust emissions and how those processes vary across time, land-use, and among vegetation and soil types. This includes a distributed network of passive dust traps in grazing lands, in off-highway vehicle use areas, in national parks with limited land disturbance, on oil and gas pads, and along unpaved roadways. We have active samplers that are measuring atmospheric concentrations of dust located in Canyonlands National Park. Additionally, we have a network of automated cameras that document visibility that are being used to quantify how dust impacts visual resources. We also maintain a highly instrumented monitoring site that is part of the National Wind Erosion Network. Data from this site are being used to develop wind erosion models applicable to all land types.
Important Results
Results from this work suggest dust emissions regionally are strongly impacted by the interaction of land use and drought. Some of the largest dust sources are associated with off-highway vehicle use and overgrazing by domestic livestock. In our distributed network, we have observed dust production increasing with temperatures and decreasing precipitation. However, the strength of these climate-dust relationships vary with land use. In general, our results suggest that roads and other highly disturbed areas are producing several time more dust per unit area than general grazing lands; however, due to the relatively small area occupied by roads, grazing lands still produce the vast majority of dust regionally.
Future Directions
Next steps from this work will include 1) understanding how dust is impacting visual resources regionally, 2) incorporating process-based wind erosion modelling to understand how management scenarios might impact dust processes, and 3) provide decision support tools to assess dust risk based on land use and restoration practices.
Below are other science projects associated with this project.
Below are publications associated with this project.
Response of Colorado river runoff to dust radiative forcing in snow
Sediment losses and gains across a gradient of livestock grazing and plant invasion in a cool, semi-arid grassland, Colorado Plateau, USA
Wind erodibility of soils at Fort Irwin, California (Mojave Desert), USA, before and after trampling disturbance: Implications for land management
Impacts of biological soil crust disturbance and composition on C and N loss from water erosion
Spatial modeling of biological soil crusts to support rangeland assessment and monitoring
Multi-decadal impacts of grazing on soil physical and biogeochemical properties in southeast Utah
Factors controlling threshold friction velocity in semiarid and arid areas of the United States
Below are partners associated with this project.
- Overview
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 with mountain snowpack). Erosion of surface soils and subsequent emissions of dust are greatly influenced by land-use practices and climate, especially drought. In this project, the U.S. Geological Survey and collaborators are monitoring aeolian sediment movement, atmospheric dust concentrations, and related erosion and dust properties to better understand the relationship between land use (grazing by domestic livestock, unpaved roads, off highway vehicles, and oil and gas development), climate variability, and aeolian processes. Results show that dust emissions increase during drought, but these increases in erosion processes are exacerbated with common land use types, especially off-road vehicle activity.
Background & Importance
The American Dust Bowl of the 1930s produced hard-learned lessons about how misguided land use and climate variation can trigger extreme wind erosion and land degradation. During the Dust Bowl, plowing in semi-arid regions coincident with drought caused extreme wind erosion and general economic devastation. Although many lessons were learned from the Dust Bowl, we now face similar challenges but with much more varied land use demands, a larger population base, and risks of intensifying drought. Although considerable uncertainty exists, current land use and drought trends have the potential to cause destabilization of sediments that increases wind erosion, sand dune mobilization, sand storms, dust emissions, productivity loss, and desertification.
The processes controlling wind erosion and dust emissions operate at scales ranging from microns to global. Vegetation height, orientation and size of vegetation gaps, soil type, soil cover, surface roughness, wind speed, and antecedent moisture all can influence dust dynamics. The Colorado Plateau in the southwestern United States is an active aeolian system that has co-occurring land-use types which vary at fine scales over a large area, each with the potential to generate large quantities of dust due to soil surface disturbance. Land uses of concern include energy and mineral extraction, unpaved road and trail development, and livestock grazing. Many of the regional shale formations (e.g. Mancos, Chinle, and Morrison Formations) have a variety of metals and other potentially hazardous constituents that could be mobilized as dust. Although this region is only a minor contributor to global dust loads currently, it represents one area of many semi-arid regions in the world that, if destabilized by drought and land use, could become a much larger dust source. The general objective of this work is to understand how land use and climate separately and synergistically affect wind erosion and dust emissions on the Colorado Plateau.
General Methods
We are employing a variety of measurement approaches to understand the controls on dust emissions and how those processes vary across time, land-use, and among vegetation and soil types. This includes a distributed network of passive dust traps in grazing lands, in off-highway vehicle use areas, in national parks with limited land disturbance, on oil and gas pads, and along unpaved roadways. We have active samplers that are measuring atmospheric concentrations of dust located in Canyonlands National Park. Additionally, we have a network of automated cameras that document visibility that are being used to quantify how dust impacts visual resources. We also maintain a highly instrumented monitoring site that is part of the National Wind Erosion Network. Data from this site are being used to develop wind erosion models applicable to all land types.
Important Results
Results from this work suggest dust emissions regionally are strongly impacted by the interaction of land use and drought. Some of the largest dust sources are associated with off-highway vehicle use and overgrazing by domestic livestock. In our distributed network, we have observed dust production increasing with temperatures and decreasing precipitation. However, the strength of these climate-dust relationships vary with land use. In general, our results suggest that roads and other highly disturbed areas are producing several time more dust per unit area than general grazing lands; however, due to the relatively small area occupied by roads, grazing lands still produce the vast majority of dust regionally.
Future Directions
Next steps from this work will include 1) understanding how dust is impacting visual resources regionally, 2) incorporating process-based wind erosion modelling to understand how management scenarios might impact dust processes, and 3) provide decision support tools to assess dust risk based on land use and restoration practices.
- Science
Below are other science projects associated with this project.
- Data
- Publications
Below are publications associated with this project.
Filter Total Items: 19Response of Colorado river runoff to dust radiative forcing in snow
The waters of the Colorado River serve 27 million people in seven states and two countries but are overallocated by more than 10% of the river's historical mean. Climate models project runoff losses of 7-20% from the basin in this century due to human-induced climate change. Recent work has shown however that by the late 1800s, decades prior to allocation of the river's runoff in the 1920s, a fiveAuthorsT. H. Painter, J.S. Deems, J. Belnap, A.F. Hamlet, C. C. Landry, B. UdallSediment losses and gains across a gradient of livestock grazing and plant invasion in a cool, semi-arid grassland, Colorado Plateau, USA
Large sediment fluxes can have significant impacts on ecosystems. We measured incoming and outgoing sediment across a gradient of soil disturbance (livestock grazing, plowing) and annual plant invasion for 9 years. Our sites included two currently ungrazed sites: one never grazed by livestock and dominated by perennial grasses/well-developed biocrusts and one not grazed since 1974 and dominated byAuthorsJayne Belnap, Richard L. Reynolds, Marith C. Reheis, Susan L. Phillips, Frank Urban, Harland L. GoldsteinWind erodibility of soils at Fort Irwin, California (Mojave Desert), USA, before and after trampling disturbance: Implications for land management
Recently disturbed and 'control' (i.e. less recently disturbed) soils in the Mojave Desert were compared for their vulnerability to wind erosion, using a wind tunnel, before and after being experimentally trampled. Before trampling, control sites had greater cyanobacterial biomass, soil surface stability, threshold friction velocities (TFV, i.e. the wind speed required to move soil particles), andAuthorsJ. Belnap, S. L. Phillips, J. E. Herrick, J.R. JohansenImpacts of biological soil crust disturbance and composition on C and N loss from water erosion
In this study, we conducted rainfall simulation experiments in a cool desert ecosystem to examine the role of biological soil crust disturbance and composition on dissolved and sediment C and N losses. We compared runoff and sediment C and N losses from intact late-successional dark cyanolichen crusts (intact) to both trampled dark crusts (trampled) and dark crusts where the top 1 cm of the soil sAuthorsN.N. Barger, J. E. Herrick, J. Van Zee, J. BelnapSpatial modeling of biological soil crusts to support rangeland assessment and monitoring
Biological soil crusts are a diverse soil surface community, prevalent in semiarid regions, which function as ecosystem engineers and perform numerous important ecosystem services. Loss of crusts has been implicated as a factor leading to accelerated soil erosion and other forms of land degradation. To support assessment and monitoring efforts aimed at ensuring the sustainability of rangeland ecosAuthorsM. A. Bowker, J. Belnap, M. E. MillerMulti-decadal impacts of grazing on soil physical and biogeochemical properties in southeast Utah
Many soils in southeastern Utah are protected from surface disturbance by biological soil crusts that stabilize soils and reduce erosion by wind and water. When these crusts are disturbed by land use, soils become susceptible to erosion. In this study, we compare a never-grazed grassland in Canyonlands National Park with two historically grazed sites with similar geologic, geomorphic, and geochemiAuthorsJason C. Neff, Richard L. Reynolds, Jayne Belnap, Paul J. LamotheFactors controlling threshold friction velocity in semiarid and arid areas of the United States
A physical model was developed to explain threshold friction velocities u*t for particles of the size 60a??120 I?m lying on a rough surface in loose soils for semiarid and arid parts of the United States. The model corrected for the effect of momentum absorption by the nonerodible roughness. For loose or disturbed soils the most important parameter that controls u*t is the aerodynamic roughness heAuthorsBeatrice Marticorena, G. Bergametti, Jayne Belnap - Partners
Below are partners associated with this project.