Dynamic changes of land use type and carbon sinks based RS and GIS in Pingshuo opencast coal mine

In order to investigate the effect of land reclamation and ecological rehabilitation in mining area on the biogeochemical cycle of carbon, the changes of land use type and “carbon sinks” storage in mining area of 33 years from 1976 to 2009 in Pingshuo opencast mining area were analyzed by remote sensing interpretation. The results showed that the type of land use had a great change, all of the arable land (3 346.35 hm2) and forest (906.45 hm2) were changed into industrial square, stripping district, open pit, unreclaimed dump and reclaimed dump. The carbon sinks and carbon sequestration value in mine ecosystem, decreased from 602 040.22 t and 63 214.22 million RMB of 1976 to 351 173.50 t and 36 873.22 million RMB of 2009 respectively. In the period of 1990-1996 and 2001-2005, the carbon sequestration in mine ecosystem showed an ascending trend. By setting the scenarios in the study area of three land use types planed in 2009, no any reclamation measures, conventional reclamation measures and ecological reclamation were simulated. The simulation results showed that carbon sequestration of three land use types were 62 279.57, 961 622.2 and 1 250 108.86 t respectively, which indicated that the carbon sinks in land reclamation has been in principal position of the whole carbon sinks in mining area ecosystem