稻田降雨径流扰动系数的解析分析

Analytical analysis of paddy runoff disturbance coefficient

为了解降雨径流过程中,降雨强度(RI)和叶面积指数(LAI)对稻田全氮(TN)、全磷(TP)浓度的影响,本研究使用移栽初期,分蘖期末期和孕穗期的水稻做LAI为2,4,6的覆盖材料,以及LAI为0的4个水平,在5.0,12.5,25.0,50.0 mm.h-14个RI下,做模拟降雨试验。研究中用径流扰动系数来表示LAI和RI对径流氮磷浓度的影响,结果表明LAI和RI对径流扰动系数均有显著影响;通过对降雨扰动系数做解析分析可以发现,TN和TP径流扰动系数的解析方程分别可以表达为:Y^=0.070×ln(RI)-0.035×LAI+0.618(R2=0.905)和Y^=0.002×RI-0.048×LAI+0.867(R2=0.913)。

In order to investigate the effects of leaf area index （LAI） and rainfall interception （RI） on paddy total nitrogen（TN） and total phosphorus（TP） concentration in rainfall runoff process, simulated rainfall experiments were conducted by setting leaf area index （LAI） as 2, 4, 6, with rice in early transplanting stage, late tillering stage, booting stage, and treatment without leaf covering, and setting rainfall interception （RI） as 5. 0,12. 5,25.0,50. 0 mm.h^-1. Disturbance coefficient was used to express the effects of LAI and RI on paddy runoff total TN and TP concentration. The results showed that LAI and RI had significant effect on disturbance coefficient. Based on analytic analysis and coupling, analytical equation of TN and TP was respectively given as fallows ： Y = 0. 070 ×In （R/） - 0. 035 xLAI＋0. 618（R2 =0. 905） and Y =0. 002 ×RI-0. 048 ×LAI ＋0. 867（R2 =0. 913）.