赣榆县夹谷山坡面侵蚀产沙特征及其影响因素

选取江苏省连云港夹谷山径流小区作为研究区域,以花岗片麻岩砾质砂壤土作为试验土壤,分析了近20a来6种典型土地利用方式的侵蚀产沙特性,研究了坡面侵蚀产沙特征及其影响因素。结果表明:(1)不同土地利用方式的年侵蚀产沙量均随年降雨量的增大而增大,梯田水保效益显著;(2)不同土地利用方式的年产沙量具有显著差异性,对产沙量的影响大小依次为:顺坡耕作区标准小区经济林区牧草区乔木用材林区梯田小区。在不同土地利用方式下,防止土壤流失最有效的是梯田,与之相反,顺坡耕作区水土流失量最大。(3)在不同土地利用方式下,坡面侵蚀产沙量与降雨侵蚀力均表现为幂函数关系,相关性较强,达到了极显著水平。

Characteristics of Sediment Yield and Its Influencing Factors on Jiagu Hillside in Ganyu County

The research area is located on Jiagu hillside of Lianyungang City, Jiangsu Province. Soil there is granitic gneiss gravelly sandy loam. The characteristics of sediment yield and its influencing factors were analyzed based on rainfall and soil erosion data under six kinds of typical land uses in the past 20 years. Results showed that: (1) The annual sediment yield in different land utilizations increased with the annual rainfall amount, except terrace. (2) The annual sediment yield in different landuse types had significant differences. The land use types, in order of decreasing average annual soil loss, were the slope farming area, standard area, commercial forest area, grassland area, timber forest area and terrace area. Under different landuse patterns, terrace was most effective in controlling soil erosion and contrarily, slope farming area had the largest soil erosion. (3) Under different land uses, the relationship between sediment yield on hillside and rainfall erosivity could be expressed by a power function, with a high correlation coefficient reaching extremely significant level.