initial rainfall中文什么意思

例句与用法

1. when soil antecedent condition is dry and the initial rainfall intensity is high, peak surface runoff also considerably lag behind that of rainfall, because of the formation of temporary relative impermeable top layer; b ) surface runoff is controlled primarily by infiltration-excess runoff mechanism under unsaturated condition; the major fraction of surface runoff are dominated by saturated infiltration-excess runoff response, only a small fraction by return flow mechanism when soil is saturated; c ) subsurface flow is dominated by saturated runoff mechanism, and the duration of subsurface post the rainfall end is dependent upon rather the soil properties than the rainfall characteristics; d ) subsurface flow intensity in cultivated soil layer ( 0 ~ 20cm ) is high up to 35mm / h when rainfall intensity is up to 120mm / h, indicating the existing of macropores and pipe flow in cultivated layer
   2)耕作制下紫色土的产流主要机制是：1)当雨前土壤含水量未达到饱和状态时，表面产流起始时间有明显滞后现象，这与紫色土的快吸水性和较多非毛管孔隙密切相关；当雨前土壤较干燥，降雨初期雨强较大时，易形成临时相对不透水表层，表面产流峰也有明显滞后现象。2)表面径流的产流方式主要是超渗产流，当土壤达到饱和状态后，有四川大学博士学位论文小部分回归流发生，但主要是饱和超渗产流发生，因为紫色土的相对不透水层和其它透水障碍层不明显。3）壤中流主要是饱和产流，与降雨过程有明显的滞后，而且雨停后的壤中流产流历时与降雨特征无关。