Surface Runoff in Tea Gardens on Slope Land in Taihu Lake Region

A field experiment was carried out in a tea garden sitting on a hill slope in the Taihu Lake Region to study basic rules of runoff therein under natural rainfall conditions.Results show that in tea gardens under conventional tea cultivation,the annual volume of runoff reached 98.29 L·m-2,carrying away a total of 11.685 kg·hm-2 N,which was dominantly NO3--N,about 76.320% ;0.128 kg·hm-2 dissolved P,which was dominantly PO43-about 0.104 kg·hm-2;and 181.13 kg·hm-2 of sediments,which contained 0.272 kg·hm-2 N and 0.030 kg·hm-2 P.The loss coefficient of N and P was 1.008% and-0.087% and the loss rate of fertilizer N and P was 5.686% and 0.190%,respectively.Comparatively,cultivation of tea on slope land produces less runoff and lowers soil N and P loss,thus reducing the risk of agricultural non-point source pollution.