人工草地覆盖条件下降雨入渗影响因素的实验研究

Experimental study on influence factors of rainfall and infiltration under artificial grassland coverage

目前关于降雨入渗的研究很少同时探讨多种因素的影响及相应的定量关系,该文在植草坡地人工模拟降雨实验基础上,分析了人工草地盖度、雨强、土壤质地等因素对黄土坡面降雨入渗规律的影响。研究结果表明:当其他条件不变时,草地盖度越大,初始和稳定入渗率更高,入渗补给系数越大。在其他条件一定时,雨强越大,初始和稳定入渗率都越大,累积入渗量和入渗补给系数也更大。同等条件下黄绵土入渗性能优于土娄土。不同雨强下,黄绵土坡面降雨入渗率可最终表示为降雨历时和草地盖度的两参数函数;土娄土入渗率和累积入渗量均可表示为时间和草地盖度的两因素函数关系;黄绵土入渗补给系数可描述为草地盖度和雨强的两因素函数关系。

Till now there are few studies for several influence factors and corresponding quantitative relations about rainfall and infiltration. Based on experiments of artificial precipitation simulations with vegetation mulches on slope land, the influences of some main factors on precipitation and infiltration regularities, including vegeta- tion coverage, rainfall intensity and soil texture, etc, were analyzed. Results indicate that as the other conditions are fixed, the larger the grassland coverage, the higher the initial and the steady infiltration rates, and the larger the infiltration supplement coefficients. As the other conditions are fixed, the larger the rainfall intensities, the higher the initial and the steady infiltration rates, and the larger the accumulative infiltration as well as the infiltration supplement coefficients. Under the same conditions, the infiltration capacities of Huangmian soil is better than that of Lou soil. The infiltration rate is two factor functions of both rainfall time and grassland coverage at different rainfall intensities for Huangmian soil. The infiltration rate and the accumulative infiltration are both two-factor functions of time and grassland coverage for Lou soil. The infiltration supplement coefficient is both two-factor function of grassland coverage and rainfall intensities for Huangmian soil.