Studies on soil organic carbon storage in Mazongling natural conservation zone

56 samplical points were selected in Mazongling Natural Conservation Zone in order to analyse the foresty soil organic carbon content and its spatial-temporal distribution of there.The results showed that the distribution of soil organic carbon content in forest varies with soil depth,different vegetation types,and altitude.The highest soil organic carbon content was 90.88 g·kg-1 in 0-20 cm soil layers,the average was 32.47 g·kg-1,Organic carbon content was decreased with increasing depth,changes in organic carbon was higher in topsoil than deep,it was different for different points.Organic carbon content increased with altitude.The change of higher altitude organic carbon content was slow,the lower was big for human impact.The seasonal variation was obviously.Forest soil organic content of topsoil was highest in autumn,the spring and winter were next best,in summer was lowest.The organic carbon density of 0-20 cm of forest soil was 6.52 kg·m-2,and the organic carbon density of 100 cm of forest soil was from 25.26 kg·m-2.The organic carbon density in the natural conservation zone was higher than the surrounding zone.The carbon storage was from 2.26×105-2.65×105 t in 0-20 cm soil layers,it was 6.94×105-8.65×105 t in 0-100 cm.Carbon storage potential of the natural conservation zone is full,so closed forest is significance.