Effect of Land Use Change on Topsoil Organic Carbon Storage of Paddy Soil in a Hilly Landscape of Red Earth Region
In order to understand the influence of land use change on the topsoil organic carbon storage of paddy soil in the landscape scale in the red earth region of subtropical China, land use changes from 1933 to 2005 and topsoil organic carbon content under different land uses were analyzed using technologies of remote sensing (RS), geographic information system (GIS) and field survey of 1264 sites. Paddy soil transformed mutually to woodland and tea plantation with a main transition form of woodland to paddy soil. Land use changes mainly occurred at the elevation of 50 m -150 m. Among the various land uses, paddy soil exerted the organic carbon content of 14.3 g/kg, which is significantly higher than those in woodland (13.0 g/kg) and tea plantation (9.5 g/kg) (p<0.01). In addition, the variation coefficient of organic carbon in paddy soil was 26.01%, obviously lower than woodland (55.5%) and tea plantation (50.9%). From 1933 to 2005, a reduced topsoil organic carbon stock (10015 t C) occurred due to paddy soil transformed to woodland and tea plantation (1233.53 hm2), while an increased topsoil organic carbon stock (15372 t) occurred due to woodland and tea plantation transformed to paddy soil (1598.90 hm2). On the whole, top soil organic carbon stock in the paddy soil were increased from 1933 to 2005 and acted as a carbon sink. The effect of land use changes on soil organic carbon stock mainly occurred in the elevation of 50 m -150 m. Thus, the protection and increase of the rice fields in the elevation of 50m-150 m is importance to advance the soil carbon sequestration potential in the red earth region of subtropical China.
red soil hillylandscape scaleorganic carbonland use change
国家科技期刊平台
NSTL
万方数据
维普
