Climate and Human-induced Changes to Arid Lands in the Western U.S.

Water is a major driving force of change in arid land ecosystems.  Excessive precipitation or changes to the soil's infiltration capacity may result in increased surface runoff, soil erosion, arroyo development and floods.  Severe droughts can cause direct mortality in plant populations or may lead to fragmentation of landscapes by increasing the severity of wildfires.  Land uses such as livestock grazing may also contribute to ecosystem changes by modifying surface hydrology and nutrient cycling.

Past climate shifts offer insights into how plant communities and ranges change with changes in precipitation or temperatures.  Locations of current vegetation provide insights into the soil/topographic/climate conditions that constrain plant distributions. 

Water is the common thread that links the 5 projects under the Arid Lands research theme.  Each project uses water to understand project-specific aspects of arid land processes and, in particular, vegetation change. Integrating these efforts will provide broader insights into how changes in climate and land use might affect arid lands throughout the region.  This information will be used to predict future changes under different climate and land use scenarios.

1998-2003

• Climate Change, Sediment Transport Capacity, Arroyo Development, and Vegetation Change in Streams of the Southwestern United States Dr. Jonathan M. Friedman
  
  
• Interactions of Cattle Grazing and Climate on Semi-arid Ecosystem Function Dr. David A. Pyke
  
  
• Past, Recent, and Twenty-first Century Vegetation Change in the Arid Southwest Dr. Kenneth L. Cole
  
  
• Response of Semi-desert Vegetation to Predicted Climate Change: Regional Gradients in the Arid Southwest Dr. Kathryn Thomas
  
  
• Sensitivity of Semi-arid Forests and Woodlands to Climate-induced Disturbances in the Southwestern U.S. Dr. Craig D. Allen