湘南丘陵幼林林下植被覆盖对土壤侵蚀的影响

为削减缓坡梯土幼林地的水土流失，设立１０００ｍ＾２迳流小区，进行定位观测。探讨了植被覆盖对板栗幼林林地土壤侵蚀的影响。丘陵红壤区域开垦的缓坡梯地是绿化达标后泥沙的主要来源地，在无植被覆盖条件下，年土壤侵蚀蚀量可达６．４７７８ｔ／１０００ｍ＾２。植被覆盖能很好的削减土壤侵蚀量，种植面积为２４．２％－５８．４％时，年土壤侵蚀量可减少３５．４９％－５７．５５％，迳流系数平均减少２４．０９％，输沙率平均减少４０．０２％，覆盖度每增加０．１则输沙率减少０．００１９－０．００２７。加大幼林地地面植物覆盖面积和覆盖速度，是控制水土流失的有效途径，油－花生套种或连种是一保土功能很好的模式。

Effects of plant covers on soil erosion under young forests at hilly area of south Hunan

In order to control the soil erosion on the young forested land of slow-up hill, 1000m 2 runoff plot was set up as a local investigation station. Then, the effects of plants covers on the chestnut forested land were studied. Which indicated that the reclamation area at the red soil of slow-up hillside terrace is the main resource of sediment in plantation areas. Without plant covers, the amount of soil erosion is up to 6.4778t/1000m 2. When the cropped area made up for 24.2-58.4%, the soil erosion reduced 35.49%-57.55%, the runoff coefficient decreased 24.09% averagely and the sediment discharge reduced 40.02%.Within the plant community, the cover intense increases 0.1, correspondingly, the sediment discharge decreases 0.0019-0.002. To increase the plant- covered areas is a good measure for control soil erosion. The companion cropping of peanut and rape and sustained cropping are optimal model for the soil conservation.