• Red Rocks with water in front of them in the desert.
  • Clouds behind Joshua Tree and bushes.
  • Desert flowers blooming in bushes in front of mountains in the desert.
  • Setting sun reflecting of clouds of orange and blue behind a joshua tree.
  • Hoover Dam intake towers with water behind the dam showing that it is not full.


The impact of ecosystem water balance on desert vegetation: quantification of historical patterns and projection under climate change

Science Need(s)

Assessing ecosystem vulnerability to changes in climate and water resource availability within Federally managed deserts, forests, or grasslands

Grantee: U.S. Geological Survey, Southwest Biological Science Center
Principle Investigators: John Bradford, Seth Munson
Cooperative Agreement: $98,244 in non-Federal funds and $161,788 in Federal funds provided by BOR 
Project Duration: 2012-2014

Project Goal(s)

Overall goal is to understand how climate change will impact desert vegetation from a hydrological perspective. To accomplish this goal, we have the following specific objectives:
1) Simulate water balance and availability at long-term vegetation monitoring plots.
2) Compare the model output with observed vegetation patterns to identify the features of water availability that are crucial for plant species responses.
3) Assess the vulnerability/sustainability of individual plant species and functional types by simulating site-specific water balance and availability under future climate scenarios.
4) Create ecosystem-specific applied science tools to allow managers to identify species and communities at risk under future climate scenarios based on predicted changes in plant water availability. 

Brief Project Description

Explore climate change impacts on vegetation across the Desert and Southern Rockies LCCs using historical monitoring data collected from 23 sites across the Sonoran, Chihuahuan, Mojave and Colorado Plateau deserts for 30-50 years. This data will then be combined with ecosystem water balance model simulations to establish features of water availability critical for plant species response. Results will allow managers to identify species and communities at risk under future climate scenarios based on predicted changes in plant water availability. Due to the high variability in soils, incorporating a detailed understanding of soil water availability beyond bioclimatic envelope approaches in the desert Southwest is essential to accurately conduct climate change vulnerability assessments and identify relative risk of vegetation change within and across management units.

Project Location

Desert Southwest

Project Tasks

  • Synthesis of vegetation data.
  • Calibration of SoilWat model for DLCC sites.
  • Conduct simulations & data analysis.
  • Preparation of technical reports and papers.
  • Final technical reports and papers.

Project Deliverables

  • Series of fact-sheets that land managers can use to assess the vulnerability of plant species to climate change that specifically accounts for soil impacts on ecohydrologic resilience.
  • Fact-sheets for dominant vegetation types represented in the long-term data (initial evaluations indicate we have data on at least 15 of the most widespread dryland vegetation types in the Southwest).

Documents Available for Download