植物篱防蚀措施对三峡库区坡耕地微地形的影响

三峡库区是我国重要的水蚀区之一，过度农业利用引发水土流失和生态退化。采用保护性管理对坡耕地水土和营养盐流失的影响已经开展了很多研究，而基于长期试验的保护性管理措施对坡面微地形的影响，鲜有涉及。本文对位于三峡库区域地区陡坡地四种管理模式长期试验径流小区坡面地形相关参数进行了观测、分析。结果显示，与对照小麦—花生种植模式相比，采用套种紫花苜蓿植物篱、香椿植物篱能够极显著降低水土流失，坡面地形沿篱基梯级化显著。而黑麦草-籽粒苋替代模式对水土流失控制效果不稳定，且坡面地形与对照无差异。小麦-花生套种紫花苜蓿、香椿植物篱处理的坡面均形成基于篱带部的篱坎，篱坎下部侵蚀较强，篱带上淤下蚀现象明显。其中小麦-花生套种香椿植物篱小区坡面形成2级植物篱淤积坎，坎宽幅平均达到420.8 cm，淤积坎相对高差为40.4 cm，平均坡度下降1.4度。小麦-花生套种紫花苜蓿植物篱坡面形成4级篱坎平均坎宽幅为210.3 cm，平均相对高度为110.6 cm，平均坡长为238.1 cm，平均坡度下降0.3度。说明坡耕地采用植物篱技术能够减蚀截淤，显著改变微地形。针对微地形的变化，套作植物篱的坡耕地在后期宜实行坡改梯或梯级坡地配套完善灌排设施，利用已优选的植物品种设计木本与草本套种的复合植物篱，有望进一步改善土体根系分布，从而稳固篱坎，控制水土流失。该研究为植物篱技术后续管理措施优化提供了参考依据。

Effects of Hedgerow Anti-erosion Measures on Microtopography of Slope Farmland in the Three Gorge Reservoir

The Three Gorges Reservoir area is one of the important water erosion areas in my country. Excessive agricultural use causes soil erosion and ecological degradation. Many studies have been carried out on the impact of protective management on soil and water loss and nutrient loss in slope farmland, but the impact of protective management measures based on long-term experiments on slope microtopography is rarely involved. In this paper, the parameters related to the slope topography of the long-term test runoff plot of the four management models on the steep slope area located in the head area of the Three Gorges Reservoir were observed and analyzed. The results showed that, compared with the control wheat-peanut planting pattern, the interplanting of alfalfa hedgerows and Chinese toon hedgerows could significantly reduce soil erosion, and the slope terrain was significantly stepped along the hedgerow foundation. However, the effect of replacing ryegrass-grain amaranth on soil erosion control was not stable, and there was no difference between the slope topography and the control. The slopes treated with wheat-peanut interplanting alfalfa and Chinese toon hedgerows all formed hedgerows based on the hedgerows, the lower part of the hedges eroded strongly, and the phenomenon of silting and erosion on the hedgerows was obvious. Among them, the slope of the wheat-peanut interplanted Toon hedgerow plot formed a second-level hedgerow silt, with an average width of 420.8 cm, a relative height difference of 40.4 cm, and an average slope drop of 1.4 degrees. Wheat-peanut interplanting alfalfa plant hedgerows formed 4-level ridges with an average ridge width of 210.3 cm, an average relative height of 110.6 cm, an average slope length of 238.1 cm, and an average slope drop of 0.3 degrees. It shows that the hedgerow technology can reduce erosion and intercept silt, and significantly change the micro-topography. In view of the change of micro-topography, the sloping farmland interplanted with hedgerows should be transformed into terraces or cascaded slopes with complete irrigation and drainage facilities in the later stage. Using optimized plant varieties to design compound hedgerows interplanted with woody and herbaceous plants is expected to further improve soil quality. The distribution of the root system of the whole body, so as to stabilize the fence and control soil erosion. This study provides a reference for the optimization of follow-up management measures of hedgerow technology.