Use of the forest vegetation simulator to quantify disturbance activities in state and transition models

Abstract

The Forest Vegetation Simulator (FVS) has been used to provide rates of natural growth transitions under endemic conditions for use in State and Transition Models (STMs). This process has previously been presented. This paper expands on that work by citing the methods used to capture resultant vegetation states following disturbance activities; be it of natural causes or human induced. Forest Inventory and Analysis (FIA) plots were stratified by representative Potential Natural Vegetation Types (PNVTs) of the southwestern United States. Structural states within the Vegetation Dynamics Development Tool (VDDT) (i.e. STM used for forest planning) were defined based on dominant tree size, canopy cover density, and vertical story layering. A standard set of silvicultural and fire prescriptions were evaluated using FVS projections. Outputs such as post treatment vegetation states, harvest volumes, and snag generation were captured and linked to transitions in VDDT. A case study involving the ponderosa pine/bunchgrass forest ecosystem will be presented to demonstrate features of the modeling approach.

Parent Publication

• Proceedings of the First Landscape State-and-Transition Simulation Modeling Conference, June 14–16, 2011, Portland, Oregon

Citation

Weisz, Reuben; Vandendriesche, Don. 2012. Use of the forest vegetation simulator to quantify disturbance activities in state and transition models. In: Kerns, Becky K.; Shlisky, Ayn J.; Daniel, Colin J., tech. eds. Proceedings of the First Landscape State-and-Transition Simulation Modeling Conference, June 14–16, 2011, Portland, Oregon. Gen. Tech. Rep. PNW-GTR-869. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: 143-160.