不同坡形坡度径流量产生规律的试验研究

Amount of Runoff in Different Slope Shapes and Angles

为合理配置水土保持措施,有效治理坡地因径流产生侵蚀而导致的水土流失,采用室内人工模拟降雨方法,研究4种不同坡形(凸形坡、凹形坡、直线形坡、内聚直坡)、3种坡度(5°,10°,15°)在3种不同雨强(0.64,1.05,1.52mm·min^(-1))下坡面径流量产生规律,共36种组合,采用无重复全面试验法,共计降雨36场,并应用无重复三因素方差分析方法对试验结果进行分析和多重比较。结果表明:通过多重比较得到坡形对径流量影响由大到小的次序为:凹形坡、凸形坡、内聚直坡、直线坡;不同坡形、坡度、雨强以及这三个因素之间的两两交互作用对径流量的影响存在着显著的差异,其中坡度和雨强交互作用及坡形和雨强交互作用对径流量影响极显著,并且坡度和雨强交互作用>坡形和雨强交互作用,坡形和坡度交互作用对径流量影响显著;由于实验结果不服从正态分布,采用对数变换法得到服从正态分布的数据,采用哑变量处理不同坡形问题,建立了径流量和坡形、坡度、雨强的非线性回归方程,y=e^(1.9009-0.2108x1-0.4195x2-0.0879x3+0.0657podu+1.6773yuqiang),回归方程显著性检验的方差分析法结果为F=306.97,概率值<0.0001,回归方程极其显著,对实践具有一定的指导意义,表明应用哑变量处理回归方程中的分类变量问题是可行的。

Inordertogetreasonableallocatingmeasuresofwaterandsoilconservation,aswellastheeffectivegovernanceofwaterlossandsoilerosioncausedbyrunofferosionofslopes,the slope runoff regularity was studied by simulating rainfall on4different slope shapes(convex slope,concave slope,straight slope,concavestraight slope)and3grades(5.,10.,15.)under3rainfall intensity(0.64,1.05,1.52mm.min-1).The study involvedatotal of36types of combinations and36rainfalls with amethod of non-replication comprehensive experiment.The results from three factors analysis of variance,showed that theamount ofrunoff wasgreatly influenced byslopeshapes,grades and rainfall intensity.The influence of slopeshapeso runoff was asconcaveslope>convexslope>concavestraight slope>straightslope.The interaction between thetwoof the three factorsalso had significantly different degreesofinfluenceontheamount ofrunoff.And the interactions,not only between gradesand rainfallintensitybutalso between slopeand grades,were allsignificantat level0.01.The interaction between slopeand gradesissignificantat level0.05.Because the resultsdid not fit the normal distribution,a logarithmictrans for mationmethod wasadopted^....^1.9009-0.2108x1-0.4195x2-0.0879x3+0.0657podu+1.6773yuqiangtogetdatafittingthenormaldistribution,andanonlinearregressionequation(y=e),between the amount of runoff and different slope shapes written as dummy variables,grades and rainfallintensity wasestablished.The variance analysis result of significancetest of the regression equation was thatF=306.97,probability values<0.0001,showing that the regression equation is very significant,and the equation can be put into practice.