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降雨侵蚀的估算对于片状侵蚀和细沟侵蚀的预测是必不可少的.然而,伊拉克的土壤流失资料缺乏,要专门为该国设计一个降雨侵蚀参数目前尚不可能.本文用现有的月平均和年平均降雨量,推算出类似通用土壤流失方程的降雨侵蚀量.该值作为伊拉克降雨侵蚀初始近似值是令人满意的.世界研究表明,除降雨因子外,在其它因子不变的情况下,片状侵蚀和细沟侵蚀量与降雨参数成正比.最常用的降雨侵蚀参数的推求应用通用土壤流失方程,其值为降雨动量(E)与最大30min雨强(I_(30))的乘积(EI_(30)).在非洲西部,侵蚀量与暴雨动量和最大雨强时间的乘积相关较好.其他非洲人研究表明,雨强大于25毫米/h的降雨总动能与土壤流失量相关极好.与侵蚀相关的降雨因子可能有区域性.然而,要推求一个地区的降雨侵蚀因子则需要长期的降雨和土壤流失资料以及多次反复实验和昂贵的分析,这对大多数发展中国家而言还有困难.应由现有的降雨资料得出降雨侵蚀初始近似值.因此,本人试图用现有的气象资料估算降雨侵蚀量,该因子也可用于评价土壤退化状况.
Estimation of rainfall erosion is essential for the prediction of lamellar erosion and rill erosion, however, there is a lack of data on soil erosion in Iraq and it is not possible to devise a rainfall erosion parameter specifically for that country. Average and annual average rainfall, a rainfall erosion similar to that of a generalized soil loss equation is derived, which is satisfactory as an initial approximation of rainfall erosion in Iraq. World studies show that, with the exception of rainfall factors, with other factors remaining constant , Sheet erosion and rill erosion are proportional to rainfall parameters.The most commonly used rainfall erosion parameters are generalized soil loss equations, which are the product of rainfall momentum (E) and maximum 30 min rain intensity (I 30) (EI_ (30)). In western Africa, the correlation between erosion and the product of heavy rainstorm and maximum rainfall time is better.Another African studies show that the total kinetic energy of rainfall with a rainfall intensity greater than 25 mm / h is related to the amount of soil erosion Well, the erosion factors associated with erosion may be regional, however, to estimate the rainfall erosion factor in a region requires long-term rainfall and soil erosion data as well as repeated experiments and costly fractions , Which is still a problem for most developing countries. The initial rainfall eclipses should be derived from the available rainfall data and I therefore attempt to estimate the amount of rainfall eroded using available meteorological data, which can also be used to assess soil Degradation.