珠江流域土壤中碳库的存量与通量

The inventory and fluxes of carbon in soil of Pearl River basin

通过对珠江流域各主要环境介质中不同形态碳含量的分析和计算,得出该流域0～1.0 m范围内土壤碳库的存量为1.36×1013 kg,占中国陆地碳库总量的9.51%,全球碳库总量的0.907%;流域净碳输入量为4.141×1010 kg/a,碳通量912.74 kg/(hm2·a),初步计算表明珠江流域可能是陆地生态系统的一个碳汇区.另一方面,人类活动造成流域内有机碳的大量流失,其中,水土流失损失的碳8.01×109 kg/a,植物收割及森林砍伐从土壤-植物系统中携带出的有机碳高达6.26×1011 kg/a, 这将造成土壤有机质含量的降低,因此促进陆地生态系统有机碳存储是提高本流域土地质量的关键.

The paper calculates different kinds of carbon in Zhujiang (Pearl River) basin. The inventory of carbon in soil of the basin from earth surface to 1.0 m is about 1.36×1013 kg,which accounts for t 9.51% of Chinese terrestrial carbon inventory and 0.907% of the global carbon inventory. Total carbon input to soil is about 9.0009×1011 kg/a,and total carbon output is about 8.5868×1011 kg/a. The basin carbon fluxes is 912.74 kg/(hm2·a). This proved that Pearl River basin is a carbon “sink”area. Human activities lead to a large amount of carbon lose from Zhujiang basin, among which the lost carbon due to water and soil erosion is about 8.01×109 kg/a, harvestry and forest felling take out about 6.26×1011 kg/a carbon from the soil-plant systems, thus it could result in the decrease in soil organic matter and soil degradation. Promoting the contents of organic carbon of terrestrial ecosystem is the key to improving the quality of the soil in this basin.