Effects of climate change, land-use change, and invasive species on the ecology of the Cumberland forests

Abstract

Model projections suggest that both climate and land-use changes have large effects on forest biomass and composition in the Cumberland forests of Tennessee and Kentucky. These forests have high levels of diversity, ecological importance, land-use changes, and pressures due to invasive herbivorous insects and climate change. Three general circulation models project warming for all months in 2030 and 2080 and complex patterns of precipitation change. Climate changes from 1980 to 2100 were developed from these projections and used in the forest ecosystem model LINKAGES to estimate transient changes in forest biomass and species composition over time. These projections show that climate changes can instigate a decline in forest stand biomass and then recovery as forest species composition shifts. In addition, a landscape model (LSCAP) estimates changes in land-cover types of the Cumberlands based on projected land-use changes and the demise of eastern hemlock ( Tsuga canadensis (L.) Carrière) due to the spread of the hemlock adelgid ( Adelges tsugae Annand). LSCAP suggests that land-cover changes can be quite large and can cause a decline not only in the area of forested lands but also in the size and number of large contiguous forest patches that are necessary habitat for many forest species characteristic of the Cumberlands.