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 aimed and avoiding, minimizing, and mitigating undesired changes due to drought and land change.
Statement of Problem:
Drylands comprise approximately 35% of Earth’s terrestrial biomes, with over 1 billion people depending on these landscapes for their livelihoods. In the U.S., drylands comprise about 40% of the landmass and 83% of Department of Interior managed lands (excluding Alaska). A substantial rise in temperature (~ 6°C) and changes in precipitation are predicted for these regions. These water-limited ecosystems are often characterized by low resilience to warming and drying, and therefore small environmental changes can have vast and unexpected ecological consequences. With large predicted shrifts in climate for dryland regions, impacts to wildlife, livestock, and human populations dependent on these resources are likely to be profound and widespread. As a result, drylands have been identified as one of three regions that will be most vulnerable to climate change by both IPCC and the USGS Climate Change team.
Why this Research is Important:
New understanding of climate change impacts on ecosystem processes produced by this effort are informing DOI and other federal, state, tribal, and private land management decisions aimed at mitigating effects of land change and increased aridity. More specifically, new understanding regarding which plant species are likely to survive under future conditions can guide the selection of appropriate plant stock for restoration as well as enable us to predict the quality of available forage and habitat. By providing information to help distinguish ecosystem change due to climate alone from those changes attributable to land use, the results of this work are helping managers of complex, multi-use landscapes identify new management solutions. Our studies focus on the Colorado Plateau region, which covers 195,000 km2 of northern AZ, northwest NM, western CO, and southern UT. However, our findings will apply to a much larger area of the western U.S., in that many areas support the same plant species and have similar soils and climate.
Objective(s):
This project is addressing the following questions:
- What are the primary drivers of historic vegetation change in drylands of the western US? How is resilience these ecosystems mediated by biological versus physical processes?
- How will plants and soils in dryland communities respond to long-term, moderate reductions in precipitation?
- How sensitive are dryland grassland communities to extreme drought? How does sensitivity change with the seasonality of drought (cold versus warm season)? How do various drought scenarios alter grass-shrub dynamics in grasslands?
- How do dryland grassland communities to respond to combinations of drought, disturbance, and grazing? If grazing is deleterious, can altered timing of grazing help mitigate these impacts?
Methods:
This project is addressing gaps in our understanding of how vegetation and soils will respond to future climates, land use, and the interactions between these factors. We will build this understanding using a several approaches, including:
- Surveys of vegetation and soils fertility across lands with differing in land use history (grazing by domestic livestock);
- Experiments in which we manipulate precipitation to simulate future droughts;
- Using ecosystem simulation modelling; and
- Experiments where we simulate the interaction of grazing and drought.
Soil, geologic, geomorphic, climate, and vegetation data from long-term monitoring plots (2009 - 2018) in Arches, Canyonlands, and Capitol Reef National Parks, Utah, USA
These data (all data tables for the data release) represent a suite of biotic and abiotic variables that characterized plant communities and the geologic, geomorphic, edaphic, climatic, and land use history context in which distinct plant communities occur. In 2009, the National Park Service's Inventory and Monitoring program for the Northern Colorado Plateau Network (NCPN) began measuring vegetat
Biocrust cover, vegetation, and climate data across 23 years (1996-2019) from a protected grassland within Canyonlands National Park, Utah
These tabular data were compiled for/to monitor vegetation and biocrust cover in a never grazed grassland located in Canyonlands National Park. An objective, or objectives, of our study was to document potential changes in biocrust and vegetation cover and species composition as related to changes in land use and climate change. These data represent a timeseries of long-term vegetation and biocrus
Soil family particle size class map for Colorado River Basin above Lake Mead
These data were compiled to support analysis of remote sensing data using the Disturbance Automated Reference Toolset (Nauman et al., 2017). The objective of our study was to assess results of pinyon and juniper land treatments. These data represent major soil types as defined primarily by soil texture and depth, but also geology, parent material, and geomorphology for relevant features that disti
Soil geomorphic unit and ecological site group maps for the rangelands of the Upper Colorado River Basin region
This data release includes maps characterizing soil geomorphic units (SGUs), climate zones, and ecological site groups that classify landscapes by ecological potential and behavior for use in land management in the Upper Colorado River Basin (UCRB) region. Soil geomorphic units were created by analysis and grouping of ecological sites (ESs), a more detailed local system of ecological units managed
Precipitation, soil moisture, and vegetation data from 36 experimental plots in southeastern Utah, near Canyonlands National Park (2015 - 2018)
These data were compiled for a study that investigated the effects of drought seasonality and plant community composition on two dominant perennial grasses, Achnatherum hymenoides (C3 photosynthesis), and Pleuraphis jamesii (C4 photosynthesis), in a dryland ecosystem. In 2015 USGS Ecologists recorded vegetation and soil moisture data in 36 experimental plots which manipulated precipitation in two
Long-term annual aeolian dust deposition data from seven locations in southeastern Utah
These data are annual aeolian dust deposition calculations from vertical deposition at seven locations near the vicinity of Moab, Utah covering the period from 1999 to 2020. Data were collected by the U.S. Geological Survey Geosciences and Environmental Change Science Center (Denver, Colorado) and Southwest Biological Science Center (Moab, Utah) to "monitor sediment characteristics at sites select
Predictive soil property maps with prediction uncertainty at 30-meter resolution for the Colorado River Basin above Lake Mead
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30 meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, t
Long-term precipitation reduction experiment in the Colorado Plateau - Survival and mortality data from 2010 to 2018
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
Vegetation and Soils Data from Grazed and Ungrazed Watersheds in the Badger Wash Study Area, Colorado, USA
In 2004 U.S. Geological Survey biologists recorded vegetation and biological soil crust (BSC) cover by species as well as measured soil stability and compaction data along 85 transects at the Badger Wash study area in western Colorado. Soil samples were collected and processed for chemistry and texture. Using analysis of variance and nonmetric multidimensional scaling (NMDS) we assessed the cover
Aeolian mass flux, rangeland monitoring site, and unpaved road reach data
These data were compiled for monitoring and analyzing the amount of windblown (aeolian) sediment at 100 cm height near Moab, UT. Big Springs Number Eight (BSNE) field aeolian passive sediment traps are summarized by location and time period in shapefiles. Shapefiles also include attributes used to analyze patterns in the aeolian transport. Three different BSNE shapefiles represent 1) a network of
Automated Reference Toolset (ART)Data
These environmental raster covariate, geospatial vector data, and tabular data were compiled as input data for the Automated Reference Toolset (ART) algorithm. These data are a subset of all the environmetal raster covariate data used in the ART algorithm. Users are advised to read the mansuscript, associated with these data and identified as the larger work citation. It is recommended that data u
Below are publications associated with this project.
Filter Total Items: 59
Soil depth and precipitation moderate soil textural effects on seedling survival of a foundation shrub species
In drylands, there is a need for controlled experiments over multiple planting years to examine how woody seedlings respond to soil texture and the potentially interactive effects of soil depth and precipitation. Understanding how multiple environmental factors interactively influence plant establishment is critical to restoration ecology and in this case to broad-scale restoration efforts in west
Decline in biological soil crust N-fixing lichens linked to increasing summertime temperatures
Across many global drylands, biocrusts form a protective barrier on the soil surface and fill many critical roles in these harsh yet fragile environments. Previous short-term research suggests that climate change and invasive plant introduction can damage and alter biocrust communities, yet few long-term observations exist. Using a globally unique long-term record of continuous biocrust surveys fr
A quantitative soil-geomorphic framework for developing and mapping ecological site groups
Land management decisions need context about how landscapes will respond to different circumstances or actions. As ecologists’ understanding of nonlinear ecological dynamics has evolved into state-and-transition models (STMs), they have put more emphasis on defining and mapping the soil, geomorphological, and climate parameters that mediate these dynamics. The US Department of Agriculture Natural
Parameterizing an aeolian erosion model for rangelands
Aeolian processes are fundamental to arid and semi-arid ecosystems, but modeling approaches are poorly developed for assessing impacts of management and environmental change on sediment transport rates over meaningful spatial and temporal scales. For model estimates to provide value, estimates of sediment flux that encapsulate intra- and inter-annual and spatial variability are needed. Further, it
What determines the effectiveness of Pinyon-Juniper clearing treatments? Evidence from the remote sensing archive and counter-factual scenarios
In the intermountain western US, expansion of Pinyon (Pinus edulis) and Juniper (Juniperus spp.) woodlands (PJ) into grasslands and shrublands is a pervasive phenomenon, and an example of the global trend towards enhanced woody growth in drylands. Due to the perceived impacts of these expansions on ecosystem services related to biodiversity, hydrology, soil stability, fire prevention, and livestoc
Drought resistance and resilience: The role of soil moisture–plant interactions and legacies in a dryland ecosystem
In many regions of the world, climate change is projected to reduce water availability through changes in the hydrological cycle, including more frequent and intense droughts, as well as seasonal shifts in precipitation. In water-limited ecosystems, such as drylands, lower soil water availability may exceed the adaptive capacity of many organisms, leading to cascading ecological effects during (co
Regional ensemble modeling reduces uncertainty for digital soil mapping
Recent country and continental-scale digital soil mapping efforts have used a single model to predict soil properties across large regions. However, different ecophysiographic regions within large-extent areas are likely to have different soil-landscape relationships so models built specifically for these regions may more accurately capture these relationships relative to a ‘global’ model. We ask
Evaluating natural experiments in ecology: Using synthetic controls in assessments of remotely sensed land treatments
Many important ecological phenomena occur on large spatial scales and/or are unplanned and thus do not easily fit within analytical frameworks that rely on randomization, replication, and interspersed a priori controls for statistical comparison. Analyses of such large‐scale, natural experiments are common in the health and econometrics literature, where techniques have been developed to derive in
Ultra‐high‐resolution mapping of biocrusts with Unmanned Aerial Systems
Biological soil crusts (biocrusts) occur in drylands globally where they support ecosystem functioning by increasing soil stability, reducing dust emissions and modifying soil resource availability (e.g. water, nutrients). Determining biocrust condition and extent across landscapes continues to present considerable challenges to scientists and land managers. Biocrusts grow in patches, cover vast e
A hybrid approach for predictive soil property mapping using conventional soil survey data
Soil property maps are important for land management and earth systems modeling. A new hybrid point-disaggregation predictive soil property mapping strategy improved mapping in the Colorado River Basin, and can be applied to other areas with similar data (e.g. conterminous United States). This new approach increased sample size ~6-fold over past efforts. Random forests related environmental raste
Seasonal and individual event-responsiveness are key determinants of carbon exchange across plant functional types
Differentiation in physiological activity is a critical component of resource partitioning in resource-limited environments. For example, it is crucial to understand how plant physiological performance varies through time for different functional groups to forecast how terrestrial ecosystems will respond to change. Here, we tracked the seasonal progress of 13 plant species representing C3 shrub, p
Assessment of rangeland ecosystem conditions in Grand Canyon-Parashant National Monument, Arizona
Sustainability of dryland ecosystems depends on the functionality of soil-vegetation feedbacks that affect ecosystem processes, such as nutrient cycling, water capture and retention, soil erosion and deposition, and plant establishment and reproduction. Useful, common indicators can provide information on soil and site stability, hydrologic function, and biotic integrity. Evaluation of rangeland h
- Overview
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 aimed and avoiding, minimizing, and mitigating undesired changes due to drought and land change.
Statement of Problem:
Drylands comprise approximately 35% of Earth’s terrestrial biomes, with over 1 billion people depending on these landscapes for their livelihoods. In the U.S., drylands comprise about 40% of the landmass and 83% of Department of Interior managed lands (excluding Alaska). A substantial rise in temperature (~ 6°C) and changes in precipitation are predicted for these regions. These water-limited ecosystems are often characterized by low resilience to warming and drying, and therefore small environmental changes can have vast and unexpected ecological consequences. With large predicted shrifts in climate for dryland regions, impacts to wildlife, livestock, and human populations dependent on these resources are likely to be profound and widespread. As a result, drylands have been identified as one of three regions that will be most vulnerable to climate change by both IPCC and the USGS Climate Change team.
Why this Research is Important:
New understanding of climate change impacts on ecosystem processes produced by this effort are informing DOI and other federal, state, tribal, and private land management decisions aimed at mitigating effects of land change and increased aridity. More specifically, new understanding regarding which plant species are likely to survive under future conditions can guide the selection of appropriate plant stock for restoration as well as enable us to predict the quality of available forage and habitat. By providing information to help distinguish ecosystem change due to climate alone from those changes attributable to land use, the results of this work are helping managers of complex, multi-use landscapes identify new management solutions. Our studies focus on the Colorado Plateau region, which covers 195,000 km2 of northern AZ, northwest NM, western CO, and southern UT. However, our findings will apply to a much larger area of the western U.S., in that many areas support the same plant species and have similar soils and climate.
Objective(s):
This project is addressing the following questions:
- What are the primary drivers of historic vegetation change in drylands of the western US? How is resilience these ecosystems mediated by biological versus physical processes?
- How will plants and soils in dryland communities respond to long-term, moderate reductions in precipitation?
- How sensitive are dryland grassland communities to extreme drought? How does sensitivity change with the seasonality of drought (cold versus warm season)? How do various drought scenarios alter grass-shrub dynamics in grasslands?
- How do dryland grassland communities to respond to combinations of drought, disturbance, and grazing? If grazing is deleterious, can altered timing of grazing help mitigate these impacts?
Methods:
This project is addressing gaps in our understanding of how vegetation and soils will respond to future climates, land use, and the interactions between these factors. We will build this understanding using a several approaches, including:
- Surveys of vegetation and soils fertility across lands with differing in land use history (grazing by domestic livestock);
- Experiments in which we manipulate precipitation to simulate future droughts;
- Using ecosystem simulation modelling; and
- Experiments where we simulate the interaction of grazing and drought.
- Data
Soil, geologic, geomorphic, climate, and vegetation data from long-term monitoring plots (2009 - 2018) in Arches, Canyonlands, and Capitol Reef National Parks, Utah, USA
These data (all data tables for the data release) represent a suite of biotic and abiotic variables that characterized plant communities and the geologic, geomorphic, edaphic, climatic, and land use history context in which distinct plant communities occur. In 2009, the National Park Service's Inventory and Monitoring program for the Northern Colorado Plateau Network (NCPN) began measuring vegetatBiocrust cover, vegetation, and climate data across 23 years (1996-2019) from a protected grassland within Canyonlands National Park, Utah
These tabular data were compiled for/to monitor vegetation and biocrust cover in a never grazed grassland located in Canyonlands National Park. An objective, or objectives, of our study was to document potential changes in biocrust and vegetation cover and species composition as related to changes in land use and climate change. These data represent a timeseries of long-term vegetation and biocrusSoil family particle size class map for Colorado River Basin above Lake Mead
These data were compiled to support analysis of remote sensing data using the Disturbance Automated Reference Toolset (Nauman et al., 2017). The objective of our study was to assess results of pinyon and juniper land treatments. These data represent major soil types as defined primarily by soil texture and depth, but also geology, parent material, and geomorphology for relevant features that distiSoil geomorphic unit and ecological site group maps for the rangelands of the Upper Colorado River Basin region
This data release includes maps characterizing soil geomorphic units (SGUs), climate zones, and ecological site groups that classify landscapes by ecological potential and behavior for use in land management in the Upper Colorado River Basin (UCRB) region. Soil geomorphic units were created by analysis and grouping of ecological sites (ESs), a more detailed local system of ecological units managedPrecipitation, soil moisture, and vegetation data from 36 experimental plots in southeastern Utah, near Canyonlands National Park (2015 - 2018)
These data were compiled for a study that investigated the effects of drought seasonality and plant community composition on two dominant perennial grasses, Achnatherum hymenoides (C3 photosynthesis), and Pleuraphis jamesii (C4 photosynthesis), in a dryland ecosystem. In 2015 USGS Ecologists recorded vegetation and soil moisture data in 36 experimental plots which manipulated precipitation in twoLong-term annual aeolian dust deposition data from seven locations in southeastern Utah
These data are annual aeolian dust deposition calculations from vertical deposition at seven locations near the vicinity of Moab, Utah covering the period from 1999 to 2020. Data were collected by the U.S. Geological Survey Geosciences and Environmental Change Science Center (Denver, Colorado) and Southwest Biological Science Center (Moab, Utah) to "monitor sediment characteristics at sites selectPredictive soil property maps with prediction uncertainty at 30-meter resolution for the Colorado River Basin above Lake Mead
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30 meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, tLong-term precipitation reduction experiment in the Colorado Plateau - Survival and mortality data from 2010 to 2018
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 aVegetation and Soils Data from Grazed and Ungrazed Watersheds in the Badger Wash Study Area, Colorado, USA
In 2004 U.S. Geological Survey biologists recorded vegetation and biological soil crust (BSC) cover by species as well as measured soil stability and compaction data along 85 transects at the Badger Wash study area in western Colorado. Soil samples were collected and processed for chemistry and texture. Using analysis of variance and nonmetric multidimensional scaling (NMDS) we assessed the coverAeolian mass flux, rangeland monitoring site, and unpaved road reach data
These data were compiled for monitoring and analyzing the amount of windblown (aeolian) sediment at 100 cm height near Moab, UT. Big Springs Number Eight (BSNE) field aeolian passive sediment traps are summarized by location and time period in shapefiles. Shapefiles also include attributes used to analyze patterns in the aeolian transport. Three different BSNE shapefiles represent 1) a network ofAutomated Reference Toolset (ART)Data
These environmental raster covariate, geospatial vector data, and tabular data were compiled as input data for the Automated Reference Toolset (ART) algorithm. These data are a subset of all the environmetal raster covariate data used in the ART algorithm. Users are advised to read the mansuscript, associated with these data and identified as the larger work citation. It is recommended that data u - Publications
Below are publications associated with this project.
Filter Total Items: 59Soil depth and precipitation moderate soil textural effects on seedling survival of a foundation shrub species
In drylands, there is a need for controlled experiments over multiple planting years to examine how woody seedlings respond to soil texture and the potentially interactive effects of soil depth and precipitation. Understanding how multiple environmental factors interactively influence plant establishment is critical to restoration ecology and in this case to broad-scale restoration efforts in westDecline in biological soil crust N-fixing lichens linked to increasing summertime temperatures
Across many global drylands, biocrusts form a protective barrier on the soil surface and fill many critical roles in these harsh yet fragile environments. Previous short-term research suggests that climate change and invasive plant introduction can damage and alter biocrust communities, yet few long-term observations exist. Using a globally unique long-term record of continuous biocrust surveys frA quantitative soil-geomorphic framework for developing and mapping ecological site groups
Land management decisions need context about how landscapes will respond to different circumstances or actions. As ecologists’ understanding of nonlinear ecological dynamics has evolved into state-and-transition models (STMs), they have put more emphasis on defining and mapping the soil, geomorphological, and climate parameters that mediate these dynamics. The US Department of Agriculture NaturalParameterizing an aeolian erosion model for rangelands
Aeolian processes are fundamental to arid and semi-arid ecosystems, but modeling approaches are poorly developed for assessing impacts of management and environmental change on sediment transport rates over meaningful spatial and temporal scales. For model estimates to provide value, estimates of sediment flux that encapsulate intra- and inter-annual and spatial variability are needed. Further, itWhat determines the effectiveness of Pinyon-Juniper clearing treatments? Evidence from the remote sensing archive and counter-factual scenarios
In the intermountain western US, expansion of Pinyon (Pinus edulis) and Juniper (Juniperus spp.) woodlands (PJ) into grasslands and shrublands is a pervasive phenomenon, and an example of the global trend towards enhanced woody growth in drylands. Due to the perceived impacts of these expansions on ecosystem services related to biodiversity, hydrology, soil stability, fire prevention, and livestocDrought resistance and resilience: The role of soil moisture–plant interactions and legacies in a dryland ecosystem
In many regions of the world, climate change is projected to reduce water availability through changes in the hydrological cycle, including more frequent and intense droughts, as well as seasonal shifts in precipitation. In water-limited ecosystems, such as drylands, lower soil water availability may exceed the adaptive capacity of many organisms, leading to cascading ecological effects during (coRegional ensemble modeling reduces uncertainty for digital soil mapping
Recent country and continental-scale digital soil mapping efforts have used a single model to predict soil properties across large regions. However, different ecophysiographic regions within large-extent areas are likely to have different soil-landscape relationships so models built specifically for these regions may more accurately capture these relationships relative to a ‘global’ model. We askEvaluating natural experiments in ecology: Using synthetic controls in assessments of remotely sensed land treatments
Many important ecological phenomena occur on large spatial scales and/or are unplanned and thus do not easily fit within analytical frameworks that rely on randomization, replication, and interspersed a priori controls for statistical comparison. Analyses of such large‐scale, natural experiments are common in the health and econometrics literature, where techniques have been developed to derive inUltra‐high‐resolution mapping of biocrusts with Unmanned Aerial Systems
Biological soil crusts (biocrusts) occur in drylands globally where they support ecosystem functioning by increasing soil stability, reducing dust emissions and modifying soil resource availability (e.g. water, nutrients). Determining biocrust condition and extent across landscapes continues to present considerable challenges to scientists and land managers. Biocrusts grow in patches, cover vast eA hybrid approach for predictive soil property mapping using conventional soil survey data
Soil property maps are important for land management and earth systems modeling. A new hybrid point-disaggregation predictive soil property mapping strategy improved mapping in the Colorado River Basin, and can be applied to other areas with similar data (e.g. conterminous United States). This new approach increased sample size ~6-fold over past efforts. Random forests related environmental rasteSeasonal and individual event-responsiveness are key determinants of carbon exchange across plant functional types
Differentiation in physiological activity is a critical component of resource partitioning in resource-limited environments. For example, it is crucial to understand how plant physiological performance varies through time for different functional groups to forecast how terrestrial ecosystems will respond to change. Here, we tracked the seasonal progress of 13 plant species representing C3 shrub, pAssessment of rangeland ecosystem conditions in Grand Canyon-Parashant National Monument, Arizona
Sustainability of dryland ecosystems depends on the functionality of soil-vegetation feedbacks that affect ecosystem processes, such as nutrient cycling, water capture and retention, soil erosion and deposition, and plant establishment and reproduction. Useful, common indicators can provide information on soil and site stability, hydrologic function, and biotic integrity. Evaluation of rangeland h