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作为中国西南长江上游众多峡谷、深谷的典型代表 ,虎跳峡地区的土壤侵蚀是一个严重的环境问题。为了解决侵蚀问题 ,大面积的适宜荒山已经植树造林。云南松是运用最广的造林树种之一。本研究试图以虎跳峡地区1993年的情况为例 ,探讨云南松林土壤侵蚀控制的水文效应及其潜能。研究发现 ,云南松密林能够截留 31.1%的降雨量。林下的土壤溅蚀量 (4.9kg.m- 2 )比裸地上的 (6 .1kg.m- 2 )降低了 19.7%。松林内的土壤流失总量与裸地的5 7.9g.m- 2 比较 ,降低到 32 .9g.m- 2 ,表明松林减少了 43.19%的土壤流失。实验指出 ,降雨强度对这里的土壤流失 ,以及云南松林的侵蚀控制作用有明显的影响。另一方面 ,研究也发现松林能够产生较大直径的叶滴 ,引起林下的叶滴溅蚀 ;而且 ,松林并不能明显地减少地表径流。然而 ,从综合作用来看 ,云南松密林具有土壤侵蚀控制的净效应。与茂密的草丛相比 ,松林侵蚀控制的效果相对较低。
As a typical representative of numerous gorges and valleys in the upper reaches of the Yangtze River in the southwest of China, soil erosion in the Hutiaoxia Gorge area is a serious environmental issue. In order to solve the erosion problem, a large area suitable for afforestation has afforestation. Yunnan pine is one of the most widely used afforestation species. This study attempts to take the case of the Tiger Leaping Gorge area in 1993 as an example to investigate the hydrological effects and potential of soil erosion control in Yunnan pine forests. The study found that Pinus yunnanensis can catch 31.1% of the rainfall. Soil erosion under the forest (4.9 kg.m-2) was 19.7% lower than that of the bare soil (6.1 kg.m-2). The total soil loss in the pine forest was reduced to 32.9 g · m -2 compared with 5 7.9 g · m -2 in the bare land, indicating that the pine forest reduced the soil loss by 43.19%. Experiments show that rainfall intensity has a significant impact on soil erosion and erosion control in Yunnan pine forests. On the other hand, the study also found that pine forests are capable of producing larger diameter leaf droplets, causing leaf drop splashing under the forest; moreover, pine forests do not significantly reduce surface runoff. However, from a comprehensive point of view, the Yunnan pine forests have the net effect of soil erosion control. Compared with dense grass, pine forest erosion control effect is relatively low.