基于大范围自动土壤水分观测站的优先流研究

为了探讨在农作物生长条件下土壤水分优先流存在的普遍性和影响因素以及强度,利用山东省2009年建设的45个自动土壤水分观测站资料,从宏观层面进行了客观分析.结果表明,降水量或灌溉量的增加,会导致优先流的发生概率和强度增加；在不同降水或灌溉量条件下,土壤表层初始含水率对优先流发生概率有不同影响；优先流的发生概率为:沙壤大于壤土,壤土大于粘土.研究表明,农田土壤水分优先流是普遍存在的概率事件,优先流发生概率和强度受降水或灌溉量、土壤初始含水率、土壤质地综合影响,而且呈现一定的非线性特征.

Studies on Soil Moisture Preferential Flow Based on Large-scale Automatic Soil Moisture Observatory

In order to discuss the universality, influencing factors and strength of preferential flow under the condition of crop, the author did macroscopically objective analysis based on the large amounts of data of 45 automatic soil moisture observation stations which were built in Shandong Province in 2009. The results showed that with precipitation or irrigation quantity increasing, the emergence probability and strength of preferential flow would grow. Under different precipitation or irrigation quantity, the surface soil initial moisture content had different effects on the emergence probability of preferential flow. The emergence probability of preferential flow on different soil texture was sand soil greater than loam, loam greater than clay loam. The research showed that the farmland preferential flow was a universally existent probability event, and the emergence probability and strength of preferential flow were closely associated with soil texture, initial soil moisture content, the precipitation and irrigation amount, and it presented certain nonlinear characteristics.