石质边坡枯枝落叶层的水土保持功能研究

Studies on Soil and Water Conservation Functions of Litter Layers on Rocky Slope

为了解石质边坡枯枝落叶层的水土保持功能,对广东省顺德区大睡牛岗石质边坡枯枝落叶的蓄积量,枯枝落叶持水性能,枯枝落叶减少土壤侵蚀量,枯枝落叶层下土壤理化性质等内容进行了研究.结果表明：大睡牛岗枯枝落叶蓄积量为219.18 g/m2.枯枝落叶层最大持水率为64％～75％.枯枝落叶层厚度及径流深度影响径流流出时间,随着枯枝落叶厚度的增加,径流流出时间延长,随径流深度增大,径流时间缩短.覆盖枯枝落叶层能极显著地提高土壤抗冲性,与未覆盖枯枝落叶的模拟边坡相比,坡度30.,枯枝落叶2 cm,径流深度1 cm条件下,下坡、中坡、上坡枯枝落叶可减少87.80％以上的土壤侵蚀量.大睡牛岗豆科植被较多的坡位（下坡与上坡）其枯枝落叶层下土壤理化性质优于豆科植被较少的坡位（平台与中坡）.

In order to explore the soil and water conservation functions of litter layers on rocky slope, litter storage, water-holding capacity of litter, amount of soil erosion reduced by litter, the soil physical and soil chemical properties under litter layers had been measured on Dashuiniu hilllock in Shunde District of Foshan City in Guangdong Province. The results showed that the litter storage was 219. 18 g/m2 in Dashuiniu hilllock. The saturated water-holding capacity of litter ranged from 64% to 750%. Litter retarding effect on runoff was related to litter thickness and runoff depth, the time of runoff flow retarded by litter increased with the increase of litter thickness, the time of runoff flow retarded by litter decreased with the increase of runoff depth. Litter could increase soil antiscour ability compared with bare simulation slope, the litter of upper-slope, middle-slope and lower-slope could decrease more than 87.80% of soil erosion amount under 30% simulation slope with 2 cm litter and 1 cm runoff depth. On the slope positions with more leguminous plants （lower-slope and upper-slope）, the physical and chemical properties of soil were better than those of the slope positions with less leguminous plants （platform and middle-slope）.