Changes in vegetation carbon stocks between 1978 and 2007 in central Loess Plateau, China

摘要

To control soil and water loss and environmental degradation, shelter/protective forests were established in the Loess Plateau as a component of the ThreeNorth Shelter Forest Program (TNSFP). With the development of the TNSFP in this region, the effects of shelter forests in the Loess Plateau on carbon (C) stock have been investigated. To assess the effects of shelter forests in the Loess Plateau on the C stock, we utilized the data obtained from field investigations and Landsat ETM? images to assess the C stocks (aboveground and belowground carbon) of shelter forests in the central Loess Plateau in China (11.94 (10 6 ha) during the TNSFP construction period (from 1978 to 2007). We also performed an uncertainty analysis up-scaling from field plots to the study area. The total vegetation C stocks increased significantly from 144 Tg in 1978, to 26(Tg in 2007, and shelter forests accounted for 80 % of total C stocks. The annual mean C sink was 4.28 Tg year(-1) for the vegetation. Shelter forests were estimated to have sequestered 2.55 Tg year(-1) biomass C and conserved 3.35 Tg year(-1) soil C. These results suggest that the shelter forests in the central Loess Plateau have acted as a C sink since the initiation of the TNSFP in 1978. Furthermore, afforestation and reforestation have a significant effect on C sequestration.