Forecasting changes in sagebrush distribution and abundance under climate change: integration of spatial, temporal, and mechanistic models

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Project Overview

The goal of this project is to forecast the effect of climate change on the distribution and abundance of big sagebrush in order to inform conservation planning, and sage grouse management in particular, across the Intermountain West. The novelty of the work will be the synthesis of models based on spatial, temporal, and mechanistic relationships between climate and sagebrush cover.

The project will:

  • Culminate in a working group meeting, bringing together land managers and researchers to draft management recommendations.
  • Take advantage of mechanisms already in place to efficiently disseminate this report to management agencies.

One Year Update

The team is modeling the current distribution and abundance of sagebrush using a dynamic global vegetation model (DGVM) known as LPJ-GUESS. LPJ-GUESS is well-suited for modeling vegetation dynamics at large spatial scales, and can incorporate disturbances such as fire to improve forecasts of how distributions may shift in the future. This is the first group to model sagebrush using this approach. Most of the work to date has focused on determining the best set of parameters to use for this species.

The researchers have improved how the model handles seedling establishment by adapting a sagebrush regeneration model to run in LPJ-GUESS. They are also conducting a sensitivity analysis to determine which plant traits have the biggest impact on model projections. This analysis will help to prioritize additional model development by identifying the traits for which accurate estimates are most important. The model fine-tuning has utilized historic climate observations, but the team is also working on downscaling the CMIP5 climate projections. These data will be used as inputs in the model once the team has completed the process of determining optimal sagebrush parameters.

Meanwhile, other team members are working on a region-wide analysis of longitudinal data that will link interannual variability in climate with sagebrush performance. Finally, they are developing an abundance-based species distribution model for big sagebrush. The team finalized these analyses in late 2015 and held a working group meeting in December to compare the results from the three different modeling approaches.

Project Documents

Theme: Climate Change, Plants

Project start date: 1/1/2015

Fiscal year funded: 2014

Project status: Active

Project managers: Dr. Peter Adler, Utah State University