title: Estimating carbon sequestration in the piedmont ecoregion of the United States from 1971 to 2010.
abstract: BACKGROUND
  Human activities have diverse and profound impacts on ecosystem carbon cycles. The Piedmont ecoregion in the eastern United States has undergone significant land use and land cover change in the past few decades. The purpose of this study was to use newly available land use and land cover change data to quantify carbon changes within the ecoregion. Land use and land cover change data (60-m spatial resolution) derived from sequential remotely sensed Landsat imagery were used to generate 960-m resolution land cover change maps for the Piedmont ecoregion. These maps were used in the Integrated Biosphere Simulator (IBIS) to simulate ecosystem carbon stock and flux changes from 1971 to 2010.
  
  
  RESULTS
  Results show that land use change, especially urbanization and forest harvest had significant impacts on carbon sources and sinks. From 1971 to 2010, forest ecosystems sequestered 0.25 Mg C ha-1yr-1, while agricultural ecosystems sequestered 0.03 Mg C ha-1yr-1. The total ecosystem C stock increased from 2271 Tg C in 1971 to 2402 Tg C in 2010, with an annual average increase of 3.3 Tg C yr-1.
  
  
  CONCLUSIONS
  Terrestrial lands in the Piedmont ecoregion were estimated to be weak net carbon sink during the study period. The major factors contributing to the carbon sink were forest growth and afforestation; the major factors contributing to terrestrial emissions were human induced land cover change, especially urbanization and forest harvest. An additional amount of carbon continues to be stored in harvested wood products. If this pool were included the carbon sink would be stronger.
authors.affiliation: Western Geographic Science Center, USGS, Menlo Park, CA 94025 USA ; San José State University Research Foundation, San José, CA 95112 USA.
authors.forename: Jinxun
authors.identifier: 0000-0003-0561-8988
authors.initials: J
authors.lastname: Liu
authors.affiliation: Western Geographic Science Center, USGS, Menlo Park, CA 94025 USA.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Sleeter
authors.affiliation: USGS, 12201 Sunrise Valley Drive, Reston, VA 20192 USA.
authors.forename: Zhiliang
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: USDA Forest Service, Northern Research Station, Durham, NH 03824 USA ; USDA Forest Service, Washington Office R&D, Washington DC, 20250 USA.
authors.forename: Linda S
authors.initials: LS
authors.lastname: Heath
authors.affiliation: Arctic Slope Regional Corporation, Contractor to USGS EROS, Sioux Falls, SD 57198 USA.
authors.forename: Zhengxi
authors.initials: Z
authors.lastname: Tan
authors.affiliation: Western Geographic Science Center, USGS, Menlo Park, CA 94025 USA.
authors.forename: Tamara S
authors.initials: TS
authors.lastname: Wilson
authors.affiliation: Western Geographic Science Center, USGS, Menlo Park, CA 94025 USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Sherba
authors.affiliation: Jiangsu Key Laboratory of Agricultural Meteorology, Nanjing University Of Information Science And Technology, Nanjing, 210044 China.
authors.forename: Decheng
authors.initials: D
authors.lastname: Zhou
keywords: Carbon change; IBIS model; Land-use change; Piedmont ecoregion