不同生态脆弱区土壤侵蚀对土地生产力影响对比研究

Soil Erosion and Its Relations to Slope Field Productivity in Hilly Gully Area of Loess Plateau and Dry-hot Valley of Jinshajiang River

通过外业调查、实验测试、大田模拟试验等方法,在土壤侵蚀特征分析基础上,对黄土丘陵和金沙江干热河谷2个生态脆弱区由于土壤侵蚀导致的坡耕地土地生产力衰退进行了对比研究。结果显示,不同生态脆弱区无任何水土保持措施的坡耕地土壤侵蚀,在导致可耕作土层变薄的同时,都造成了不同程度的土壤物理性能和入渗能力下降,土壤养分流失以及土地生物生产能力的衰退。相同强度土壤侵蚀对坡耕地土地生产力的影响,干热河谷区大于黄土丘陵区,是黄土丘陵区的2.1～2.9倍。

<Abstrcat> Soil erosion properties are analyzed to determine the impacts of soil erosion on land productivity in the Loess Plateau and the Dry-hot Valley of Jinsha River. Analysis methods used include field survey, laboratory experiments and simulation tests. Results show that soil erosion on sloping fields not only causes soil nutrient loss, but also causes degradation of soil physical properties and diminished soil infiltration capability. The consequence of theses changes brought by soil erosion is a reduction in land productivity. The impacts of similar soil erosion on the productivity of land in the Dry-hot Valley are more severe than those in the Loess Plateau, averaging 2.1 to 2.9 times more serious.