内蒙古黄土丘陵沟壑区降雨侵蚀力时间变化规律研究

降雨侵蚀力指由降雨引起土壤侵蚀的潜在能力,是影响土壤侵蚀的最主要因子之一。以内蒙古准格尔旗沙圪堵气象站45年的日降雨资料为基础,选取适合本地区的降雨侵蚀力模型,分析内蒙古黄土丘陵沟壑区的降雨量与降雨侵蚀力的关系。结果表明年降雨侵蚀力曲线与年降雨量曲线走向基本上是一致的。年内降雨侵蚀力分布与降雨量的年内分布规律也基本相同,所不同的是降雨侵蚀力的季节变化要明显大于降水量的季节变化。二者的回归关系比较表明,降雨量与降雨侵蚀力的关系以幂函数关系表示,相关性系数最大,并且月降雨量与降雨侵蚀力的相关性要明显比年降雨量与降雨侵蚀力的相关性增强,这主要是受降雨强度的影响。降雨侵蚀力在年内主要集中在6~9月,以8月最大。

The Change Regularity of Rainfall Erosivity in the Loess Hilly and Gully Regions of Inner Mongolia

The rainfall erosivity is a latency capability of soil erosion by rainfall and the most influencing and important factor for soil erosion.Based on daily rainfall data of Shagedu weather station in Zhunge'er Banner of Inner Mongolia,according to the adaptive rainfall erosivity model,the relationship between rainfall and rainfall erosivity in the loess hilly and gully regions of Inner Mongolia is analyzed.It shows that the curve between rainfall erosivity and rainfall amount year-by-year is identical,and annual rainfall erosivity and rainfall is the same,too,which dissimilarity is the season change of rainfall erosivity is more obvious than that of rainfall.By regression comparison,the relevance coefficient is biggest,as the relationship between rainfall and rainfall erosivity is expressed by power function.And the relevance coefficient of the monthly rainfall and rainfall erosivity more strengthen obviously than annual rainfall and rainfall erosivity,which is mainly influenced by rainfall intensity.The rainfall erosivity is fasten on June to September,and it's the biggest in August.