青海高寒农区不同土地利用方式下土壤有机碳含量变化研究

利用有机碳密度分组法,研究了青海省高寒农区退耕还林（草）前后4种土地利用方式（农田、人工林、林草间作、原生样地）下的土壤总有机碳、轻组含量和轻组有机碳的变化趋势。结果表明土壤总有机碳含量由高到低依次为林草间作〉原生样地〉人工林〉农田,林草间作与人工林、农田2组样地间差异显著（P〈0.05）;土壤轻组有机碳由高到低依次为原生样地〉林草间作〉人工林〉农田,原生样地与人工林和农田间差异显著（P〈0.05）;比较轻组含量,其序列依次为原生样地〉林草间作〉人工林〉农田。原生样地的开垦会导致土壤总有机碳和轻组有机碳的下降,而农田退耕为林草间作和人工林后有利于土壤固碳能力的增加。

Changes of Organic Carbon in Soil under Different Land Use Patterns in Alpine Agricultural Region of Qinghai

Using organic carbon density grouping method,the change trends of soil total organic carbon (SOC),light fraction content and light fraction organic carbon under 4 land use patterns of returning cultivated land to forest (cropland,artificial forest,inter-cropping of forest and grassland and original sample plot ) in alpine agricultural region of Qinghai were studied.The content of SOC was in order:intercropping of forest and grassland > original sample plot > artificial forest > cropland.There was significan...