Chen, Hua (School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849, Phone: 334-844-1057; Fax: 334-844-1084; Email: chenhua@auburn.edu)

Effects of cropland abandonment and forest regrowth on terrestrial carbon storage in Southeastern US

Hua Chen *, Hanqin Tian, Chi Zhang, Mingliang Liu, Shufen Pan

Southeast is thought to be the largest carbon sink across the six major bioclimatic regions of the conterminous United States. Cropland abandonment and forest regrowth are two potentially important factors to be responsible for this carbon sink. The objective of this study is to examine how land uses change, especially cropland abandonment and forest regrowth, on terrestrial carbon storage in southeastern US. We have compiled and developed the historical annual cropland gridded data set of southeastern US between 1850 and 2000 with a spatial resolution of 4 km. This data set has been used as input of the Terrestrial Ecosystem Model (TEM) to simulate land use effects on carbon fluxes and storage in the region. According to the preliminary analysis, our results indicate that, from 1850 to 2000, cropland area decreased more than 50%, most of which was converted to forests. Our preliminary analysis indicates that forest regrowth after cropland abandonment has resulted in a carbon uptake in the southeast, and the magnitude of the carbon sink varies over space and time.