Threat Assessments on California Rangelands

Average percent change in multiple ecosystem services from 2010 to 2040

Example ecosystem services  Map

These maps display the average percent change in three rangeland ecosystem services – soil carbon, critical habitat and water availability – from 2010 to 2040 for three IPCC-SRES scenarios (A1B, A2 and B1) and two climate projections (warm, wet future and hot, dry future). Soil carbon is soil organic carbon carbon (up to 20 cm in depth), and was estimated annually from 2006 to 2050 by the U.S. Geological Survey's General Ensemble Biogeochemical Modeling System (GEMS) ( See Carbon description page for model details. Critical habitat is defined as critical priority conservation areas mapped in the California Rangeland Conservation Coalition's focus area map ( (TNC, 2007). Change in critical habitat is described on the critical habitat description page. Water availability is defined as recharge plus runoff. Future change in water availability was modeled using the U.S. Geological Survey's Basin Characterization Model (BCM), a regional water balance model (Flint et al. 2013, Flint and Flint, 2012). See Recharge/Runoff description page for model details. Scenarios of critical habitat and carbon for 2040 were coupled with percent change in water availability under two climate projections for climate period 2010-2039. All model outputs were averaged by watershed area. Watershed boundaries are from the 8-digit Watershed Boundary Dataset (

Average percent change in multiple ecosystem services was calculated as:

AVEES = (ΔH + ΔC + ΔW)/3


  • AVEES = average percent change in ecosystem services
  • ΔC = percent change in grassland soil carbon sequestration potentialtotal from 2010 to 2040, averaged by watershed area
  • ΔW = percent change in water availability from climate period 1981-2010 to 2010-2039, averaged by watershed


Flint, L.E., A.L. Flint, J.H. Thorne, and R. Boynton. 2013. Fine-scale hydrologic modeling for regional landscape applications: the California Basin Characterization Model development and performance. Ecological Processes 2:25. Available online at:

Flint, L.E. and Flint A.L. 2012. Downscaling future climate scenarios to fine scales for hydrologic and ecologic modeling and analysis. Ecological Processes 1:2. Available online at:

Leh, M. D. K., M. D. Matlock, E. C. Cummings, and L. L. Nalley. 2013. Quantifying and mapping multiple ecosystem services change in West Africa. Agriculture, Ecosystems & Environment 165:6-18.

The Nature Conservancy (TNC). 2007. California Rangeland Conservation Coalition Biological Prioritization of Rangelands: Approach and Methods. Available online at: