Plant responses to drought in the southwestern United States
Land managers face challenges in the future as heat-related aridification alters the abundance, distribution, and interactions of plant species. These challenges will be daunting in the southwestern US, which is experiencing increased temperatures and prolonged droughts, resulting in reduced soil moisture in an already water-limited environment.
Background & Importance
These changes will negatively affect plant growth and may result in shifts of plant community composition and ecosystem function. The broad-scale effects of aridification and complex spatial heterogeneity of abiotic and biotic conditions across the southwestern U.S. makes it difficult to use site-specific data to assess environment-plant relationships.
We are conducting regional cross-site analysis to identify at risk plant species, functional types, and plant communities that can help managers mitigate and adapt to shifts in plant community composition, distinguish changes due to climate versus land use, and construct future conservation policies.
Recent elevated temperatures and prolonged droughts in many already water-limited regions throughout the world, including the southwestern United States, are likely to intensify according to future model projections. This warming and drying can negatively affect perennial vegetation and lead to the degradation of ecosystem properties. To make accurate predictions of plant responses, it is valuable to determine the long-term dynamics of plant species associated with historical conditions.
General Methods
For this research, we are determining how plant species and functional types across a wide range of ecosystems in the southwestern U.S. have changed with drought and elevated temperatures to inform predictions of future plant species assemblages.
We are using a fusion of ground-based monitoring and remote sensing to assess plant responses. Because soils, landform, and geology have a strong influence on water-availability in this region, we are integrating these environmental characteristics to examine how they moderate environment-vegetation relationships at local to regional scales.
Results
We have completed analyses for the Colorado Plateau, Sonoran, Chihuahuan, and Mojave Deserts. Results indicate the plant species and communities that are most vulnerable to aridification and where on the landscape they are most susceptible.
These results are being used to help land managers anticipate and prepare for reductions in water availability.
Related Research Directions
- Comparing the long-term effects of drought with land-use,
- Coupling historical results with simulation modeling to predict future changes, and
- Understanding how aridification-induced plant responses affect ecosystem function (e.g., soil erosion, carbon storage, and wildlife habitat).
Below are other science projects associated with this project.
RAMPS: Restoration Assessment & Monitoring Program for the Southwest
Colorado Plateau Extreme Drought in Grassland Experiment (EDGE)
Chronic Drought Impacts on Colorado Plateau Ecosystems (Rain-Out Experiment)
Southwest Energy Exploration, Development, and Reclamation (SWEDR)
Drought Adaptation Strategies for Arid Grasslands
Drylands are highly vulnerable to climate and land use changes: what ecosystem changes are in store?
Colorado Plateau Futures: Understanding Agents of Change on the Colorado Plateau to Facilitate Collaborative Adaptation
Dryland Forest Sustainability
Big Sagebrush Ecosystem Response to Climate & Disturbance
Land managers face challenges in the future as heat-related aridification alters the abundance, distribution, and interactions of plant species. These challenges will be daunting in the southwestern US, which is experiencing increased temperatures and prolonged droughts, resulting in reduced soil moisture in an already water-limited environment.
Background & Importance
These changes will negatively affect plant growth and may result in shifts of plant community composition and ecosystem function. The broad-scale effects of aridification and complex spatial heterogeneity of abiotic and biotic conditions across the southwestern U.S. makes it difficult to use site-specific data to assess environment-plant relationships.
We are conducting regional cross-site analysis to identify at risk plant species, functional types, and plant communities that can help managers mitigate and adapt to shifts in plant community composition, distinguish changes due to climate versus land use, and construct future conservation policies.
Recent elevated temperatures and prolonged droughts in many already water-limited regions throughout the world, including the southwestern United States, are likely to intensify according to future model projections. This warming and drying can negatively affect perennial vegetation and lead to the degradation of ecosystem properties. To make accurate predictions of plant responses, it is valuable to determine the long-term dynamics of plant species associated with historical conditions.
General Methods
For this research, we are determining how plant species and functional types across a wide range of ecosystems in the southwestern U.S. have changed with drought and elevated temperatures to inform predictions of future plant species assemblages.
We are using a fusion of ground-based monitoring and remote sensing to assess plant responses. Because soils, landform, and geology have a strong influence on water-availability in this region, we are integrating these environmental characteristics to examine how they moderate environment-vegetation relationships at local to regional scales.
Results
We have completed analyses for the Colorado Plateau, Sonoran, Chihuahuan, and Mojave Deserts. Results indicate the plant species and communities that are most vulnerable to aridification and where on the landscape they are most susceptible.
These results are being used to help land managers anticipate and prepare for reductions in water availability.
Related Research Directions
- Comparing the long-term effects of drought with land-use,
- Coupling historical results with simulation modeling to predict future changes, and
- Understanding how aridification-induced plant responses affect ecosystem function (e.g., soil erosion, carbon storage, and wildlife habitat).
Below are other science projects associated with this project.