冀西北半干旱区等高植物篱面源污染控制机理

Mechanism of Contour Hedgerow's Control for Non-Point Pollution in the Semiarid Region in Northwest Hebei Province

坡面养分流失是造成面源污染的主要形式 .本研究利用冀西北黄土丘陵区的试验小区的长年观测资料 ,并结合野外全坡面大型人工模拟降雨试验及室外实验数据 ,分析了冀西北温带及半干旱地区等高植物篱对面源污染控制机理 ,得出在暴雨条件下细沟产生并导致侵蚀剧烈增加的临界坡长为 1 0～ 1 5m ;研究揭示出冀西北半干旱区面源污染形态以泥沙携带养分流失为主 。

Slope nutrient loss is an important type of non\|point pollution. The mechanism of non\|point pollution control by using plenty of natural observed data in Hilly Loess region in Northwest Hebei Province, as well as combating with the large scale artificial simulation rainfall in the field slope was analyzed. The study results show that the critical slope length was 10～15m on the condition of rainstorm, which led to the generation of rill and made the erosion amount went up obviously. The study show that the nutrient loss in sediment was the main type of non\|point pollution, the contour hedgerow the process of non point pollution by controlling the nutrient loss in sediment, then the study got the erosion control model of the contour hedgerow.