杉木新造林地水土流失规律研究初报

Studies on the Low of Soil and Water Losses in New Forestation Land of Chinese Fir

杉木(Cunninghamia lanceolata(Lamb.)Hook.)是我国南方的主要用材树种,造林时,以营造纯林为主,整地方式又以全垦挖大穴或火烧炼山后挖大穴较常见。由于南方雨水充沛,雨量集中,而且常有大雨、暴雨出现,使得新造林地发生大量水土流失,在坡度较大地段,甚至出现滑坡,造成严重的损失。本文以杉木新造林地为对象,设置径流场。

Three runoff plots were set up in the new forestation land of Chinese fir after control burning in Shaowu, Fujian province in 1992. The laws of changes in rain height, surface losses rate of soil and water were observed and studied. The results indicated that surface runoff and soil erosion on bare land is much more than those on new forestation land after control burning. Runoff coefficient of bare land is 3.8 times as that of the new forestation land. Surface runoff and surface soil losses lowered greatly after tending and earthing up of level terrace.Seasonal variations of surface runoff were mainly in fluenced by seasonal distribution of rainfall.The main reasons which caused serious surface runoff are heavy rains and rain storms.