The Research About Groundwater Recharge Coefficients Of Scale In The Eastern Slope Of The Forest Area In Gongga Mountain

Forests affect soil water movement and change conditions of runoff yield and flow Confluence through interception and occlusion of rainfall. To some extent, it can modulate the peak of flood and the runoff in dry season, control soil erosion, and improve water quality in rivers, thus not only affecting the hydrological processes of water basin, but also affecting the recharge, runoff and discharge processes in groundwater. As a result, it is significantly important to study hydrological cycle in forests area for the ground recharge. In this paper, the researches on the rainfall infiltration process and recharge coefficient in forest region have been conducted, for instance, studying the multi-scale hydrological cycle features of forest area in the East Slope of Gongga Mountain.The characteristics of the rainfall and the aquifer have been discussed and analyzed through field investigation and combination the previous data on geology, hydrogeology and hydro-meteorology. (1)In order to find the regularity of the interception mount and the time lag effect with different litter, four types of vegetation, such as immature coniferous forest, mature coniferous forest, broad-leaved forest and mixed coniferous forest, were chosen to modulate indoor artificial rainfall experiment. Comparing stratified litter test with not stratified one demonstrates that the whole litter has an impact on rainfall lag effect and the different litters play independent role on hydrology. It indicates: 1) in the litter stratified experiment,①the variability which the area affects the lag time of different decomposition litter layer is not obvious,②the inception amounts in four different litter are exponential correlation with the area, with correlation coefficient R2 up to 0.813. 2) In the litter not stratified experiment,①the lag time and inception content in immature coniferous forest are minimal in four types, while, the interception amount is maximal in broad-leaved forest.②the inception amounts in four different litter are exponential correlation with the area, with correlation coefficient R2 more than 0.84.(2) By analysis of soil's function of regulation and storage under different vegetables, It shows that soil storage capacity in Huangbeng Ditch Basin is between 1.5399×106m and 5.133×106m3, Guanjingtian station Basin is between 0.1679×106 m3and 0.557×106,and 0.06508×106m3 to 2.169×106m3 in Madao Ditch Basin. (3) By segment of the three different area basin base flow in forest region, it indicates that three station's runoff are mainly underground runoff, as well as, the proportion of the interflow are very small. (4)Through the regional water balance calculation, the recharge coefficients of precipitation infiltration in Hongbeng Ditch Basin is between 0.247and 0.494, while it is between 0.566 and 0.374 in the Ma Dao Ditch Basin.