针对目前国内外对于温带及半干旱地区植物篱的侵蚀及养分控制过程研究较少的状况,利用冀西北黄土丘陵区较为完备的试验小区的长年观测资料,并结合野外全坡面的大型人工模拟降雨试验,定量地分析黄土丘陵区坡面侵蚀分异规律,得到了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10～15m,从而以此作为植物篱在该区域布设的理论依据。本研究模拟和分析了植物篱对养分流失拦蓄的形态、植物篱改变坡面侵蚀过程、控制细沟产生以及拦蓄泥沙而达到控制侵蚀及养分的目的,对于植物篱———农作复合农林技术在温带及半干旱地区的实践具有科学价值。

Agroforestry is a newly developed technique, which includes various fields and is suitable for developing countries. Recently, the contour hedgerow-crop system has become one of the major forms of agroforestry on slopeland in developing countries. It was proved intercropping between the contour hedgerows is favorable for controlling erosion, increasing soil fertility and gaining higher benefit of the slopeland by relatively low input. The primary objective of applying hedgerows is to control erosion and non-point pollution on slopeland. The distance between contour hedgerows mainly decides the effect of erosion control and the cultivable area in the hedgerows-crop systems. Therefore, the design of the distance is very important to applying the contour hedgerow techniques. The existing studies have not paid much attention to the hedgerow's control process for erosion and nutrient in the temperate zone and semiarid region. The present study quantitatively analyzes the rules of various erosion zones on a slope by using plenty of field observed data in hilly loess area of northwest Hebei Province, as well as large-scale artificial rainfall simulation data from sloping field. Taking contour hedgerow-crop system as an example, this paper discusses the major mechanism of soil erosion and nutrient change processes, the design of level spacial structure of typical agroforestry systems in hilly area of northwest Hebei. The results showed that the critical slope length is 10-15m on the condition of rainstorm, which can control the generation of rills and make the erosion amount decrease obviously. The study provides a theoretical basis for the hedgerow plant, and the hedgerow can control the erosion and nutrient loss through changing the erosion process on slopes and control thes generation of rill erosion. The study has a scientific value for the application of the hedgerow-crops agroforestiy system in the temperate zone and semiarid region.