贵州喀斯特黄壤坡面降雨侵蚀特征研究

发布时间：2018-04-23 22:04

本文选题：喀斯特 + 黄壤　；参考：《北京林业大学》2015年硕士论文

【摘要】：本文以喀斯特黄壤土分布区的两个典型小流域为研究区域,通过小型气象站和不同土地利用类型坡面径流小区5年的观测实验,记录降雨量、降雨强度、产流量和产沙量等特征值,探究研究区的降水特征、降雨侵蚀力和侵蚀性降雨标准,产流产沙特征以及产流与产沙之间的相关关系,可以为黄壤的侵蚀预报和地区农林业生产提供必要依据,得到以下结论：EI30为计算降雨侵蚀力指标R的最佳结构形式,降雨侵蚀力指标R可以通过PI30进行简易计算。黄壤裸地的侵蚀性降雨指标应采用最大30 min降雨强度,其值在9.6-10.2mm·h-1之间；耕地的侵蚀性降雨指标应采用雨量标准；水土保持措施可明显提高侵蚀性降雨标准,较裸地和耕地分别提高55%和25%以上,复杂下垫面宜采用雨量标准,低植被覆盖下垫面宜采用最大时段雨强标准。喀斯特地貌区黄壤坡面入渗十分强烈,产流量小,径流系数较低,且在不同土地利用条件下差异不大。坡改梯、经果林、荒草地、水保林土壤侵蚀强度都在微度水平,坡耕地在中度-强度水平,坡改梯和经果林都可有效降低坡面侵蚀强度。对于耕地,少数的几次暴雨侵蚀过程贡献了绝大部分产沙量,水保林的减沙效果最为突出。降水强度对植被覆盖高的土地利用类型的产沙量影响不大。不同土地利用类型的次降雨产沙量和产流量呈明显的线性关系。
[Abstract]:In this paper, two typical small watersheds in the distribution area of karst yellow loam were used as the study area. The rainfall and intensity of rainfall were recorded through 5 years observation experiments of small meteorological stations and runoff plots on different land use types. The characteristics of precipitation, rainfall erosivity and erosive rainfall standards, the characteristics of runoff and sediment yield, and the correlation between runoff and sediment yield in the study area are explored. It can provide the necessary basis for erosion prediction of yellow soil and agricultural and forestry production in the region. The following conclusions can be drawn: 1: EI30 is the best structural form for calculating rainfall erosivity index R, and the rainfall erosivity index R can be easily calculated by PI30. The maximum rainfall intensity of 30 min and the value of 9.6-10.2mm h-1 should be adopted for the erosive rainfall index of the bare soil of yellow soil, the rainfall standard should be adopted for the erosive rainfall index of cultivated land, and the soil and water conservation measures could obviously improve the erosive rainfall standard. Compared with bare land and cultivated land, 55% and 25% higher than that of bare land and cultivated land, the rainfall standard should be used for complex underlying surface and the maximum rainfall intensity standard for low vegetation cover. The infiltration on the slope of yellow soil in karst geomorphology area is very strong, the runoff coefficient is low, and the runoff coefficient is low, and the difference is not obvious under different land use conditions. The soil erosion intensity of slope change, fruit forest, barren grassland and water conservation forest are all at the low level, the slope cultivated land is at the moderate intensity level, and the slope change ladder and forest can effectively reduce the slope surface erosion intensity. For cultivated land, a few rainstorm erosion processes contributed most of the sediment yield, and the silt reduction effect of water conservation forest was the most prominent. Precipitation intensity has little effect on sediment yield of land use type with high vegetation cover. There was a linear relationship between sediment yield and runoff in different land use types.
【学位授予单位】：北京林业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S157.1

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