典型强降雨下不同植被类型水土保持特征分析

Analysis of Runoff and Sediment of Different Vegetation Types Under Heavy Rain

设置地表径流观测场,观测强降雨下不同植被恢复5年后产流、产沙特征.试验结果表明,苦竹＋牛鞭草植被类型在此次强降雨为106.3mm情况下,产流、产沙量占其全年的15.24%和17.072%,调节降雨和抑制土壤侵蚀的能力最强;农耕地产流、产沙量占其全年的22.05%和31.65%,其中产沙量达其他3种植被类型的4.6-13.3倍,水土保持能力最弱;桦木＋牛鞭草、杂交竹＋牛鞭草植被类型因桦木生长和杂交竹间歇性采伐的原因,水土保持能力居于中等水平;对比农耕地来说,3种植被类型恢复后土壤侵蚀得到了有效控制,但强降雨下地表径流控制程度还较弱,需继续加强对土壤—植被系统的培育.

The runoff observation field was established to observe the runoff and sediment yield characteristics of different vegetation restoration types under the heavy rainfall after five years of planting.The experimental results showed that the vegetation type Pleioblastus＋Hemarthria accounted for 15.24%and 17.072%of its full-year＇s runoff and sediment yield under the heavy rainfall of 106.3mm,and the rainfall regulation and soil erosion control ability was the strongest;the farmland＇s runoff and sediment yield accounted for 22.05%and 31.65% of its full-year＇s,in which the sediment yield reached 4.6~13.3times of the other three vegetation types,and the soil and water conservation ability was the weakest;Betula luminifera＋Hemarthria and Bambusa pervariabilis x Dendrocala mopsis＋Hemarthria vegetation＇s soil and water conservation capacities were in the middle level due to the growth of Betula luminifera and intermittent harvesting of hybrid bamboo.Contrasting to the farmland,the soil erosion of other three vegetation types had been effectively controlled,but the surface runoff controlling ability was still relatively weak,so the cultivation of soil and vegetation system should be strengthened.