Forest Sciences Commons^™

Long-Term Droughtiness And Drought Tolerance Of Eastern Us Forests Over Five Decades, Matthew P. Peters, Louis R. Iverson, Stephen N. Matthews

USDA Forest Service / UNL Faculty Publications

Droughts can influence forest composition directly by limiting water or indirectly by intensifying other stressors that affect establishment, growth, and mortality. Using community assemblages of eastern US tree species and drought tolerance characteristics assessed from literature, we examine recent drought conditions in relation to the spatial distribution of species and their tolerance to drought. First we calculate and compare a cumulative drought severity index (CDSI) for the conterminous US for the periods 1960–1986 and 1987–2013 using climate division Palmer Drought Severity Index (PDSI) values and a gridded self-calibrated PDSI dataset. This comparison indicates that drought conditions in the East tend …