ASSESSING IMPACTS OF CLIMATE-CHANGE ON FORESTS - THE STATE OF BIOLOGICAL MODELING

Models that address the impacts of climate change on forests are revie wed at four levels of biological organization: global, regional or lan dscape, community, and tree. The models are compared for their ability to assess changes in fluxes of biogenic greenhouse gases, land use, p atterns of forest type or species composition, forest resource product ivity, forest health, biodiversity, and wildlife habitat. No one model can address all of these impacts, but landscape transition models and regional vegetation and land-use models have been used to consider mo re impacts than the other models. The development of landscape vegetat ion dynamics models of functional groups is suggested as a means to in tegrate the theory of both landscape ecology and individual tree respo nses to climate change. Risk assessment methodologies can be adapted t o deal with the impacts of climate change at various spatial and tempo ral scales. Four areas of research needing additional effort are ident ified: (1) linking socioeconomic and ecologic models; (2) interfacing forest models at different scales; (3) obtaining data on susceptibilit y of trees and forest to changes in climate and disturbance regimes; a nd (4) relating information from different scales.