经济林地坡长对侵蚀产流动态过程影响的模拟试验研究

经济林经营是低丘缓坡土地利用的主要方式之一,对经济林坡地水土流失问题的研究已是南方水土保持工作的重中之重.为了研究低丘缓坡经济林地坡长对坡面侵蚀产流过程的影响规律.本研究以浙江省常山县胡柚林地为例,通过野外人工模拟降雨试验法,分析探讨了该经济林地的侵蚀产流情况.得结论如下:(1)相同坡长下,当雨强大于或等于1.8 mm/min时,累积径流量增幅较大;降雨12 min后,各雨强累积径流量增幅均较明显;随着坡长的延长其对坡面累积径流量的影响逐渐明显.(2)该经济林地坡面径流量随坡长呈每隔4m有规律的起伏变化,该结果启示我们,在坡面栽植经济林时.沿坡长按每隔4 m的规律进行布局.能有效减缓坡面径流的产生.(3)相同坡长坡面产流量随雨强增大总体上呈增加趋势,雨强1.45 mm/min大约是该地区经济林地侵蚀性降雨的分界点.(4)土壤初始含水率、雨强以及坡长对产流量的综合影响可以用线性相关方程描述,其中降雨强度对产流量的影响最大.愿此研究结论能为经济林坡地水土流失的防治提供借鉴.

Simulated Study on Influence of Slope Length on Erosion Runoff Yield Process in Economic Forest

The economic forest management is one of the main land use models on low hill gentle slope, hence, study of soil and water loss on economic forest slope is the mostly important part in soil and water conservation work in south. In order to research the influence disciplinarian of the impact of slope length on the process of slope erosive runoff on low hill gentle slope region, based on the field simulated rainfall and taking Huyou forest in Changshan county of Zhejiang province, this study analyzed the runoff yield situation and results as follows; (1) under the same slope length, cumulative runoff volume increased sharply when rainfall intensity above 1. 8 mm/min. There was an obvious impact on cumulative runoff volume with increasing slope length, and it shows visible enhancement after 12 min rainfall. (2) Slope cumulative runoff volume fluctuated with increasing of slope length in the economic forest, and soil and water loss would be mitigated with planting trees of Huyou every 4 m. (3) There was an increasing tendency of runoff volume as a whole, under the same slope length, and 1. 45 mm/min rainfall intensity is a dividing point of erosive rainfall. (4) The synthetical influence of soil initial water content and rainfall intensity and slope length on runoff volume can be described by linear correlation equation and rainfall intensity plays the most prominent part. We expect this study can provide scientific gist for conservation of local soil and water loss.