营林措施对杉木幼林地水土流失的影响

A STUDY ON EFFECTS OF SOIL AND WATER LOSSES FOR SEVERAL SILVICULTURAL MEASURES IN YOUNG PLANTATION OF CHINESE FIR

通过建立１６个径流小区，对不同整地方式、抚育方式、间种绿肥和营造林模式等营林措施的杉木造林地的水土流失进行了５年的定位观测研究，结果表明，不同整地方式林地５年的土壤流失量表现为全垦＞带垦＞穴垦，穴垦比全垦、带垦分别减少４０３３％和２５４８％的土壤流失量；不同抚育方式林地５年土壤流失量表现为扩穴连带抚育（９８６９５ｔ／ｈｍ２）＞块状抚育（９２５８７ｔ／ｈｍ２）＞不抚育（４０６６ｔ／ｈｍ２），块状抚育比扩穴连带抚育减少６１９％的土壤流失；不同造林模式林地５年的水、土、肥流失均表现为：传统模式＞世行模式＞生态型模式，其中世行造林模式林地水、土、有机质和养分（Ｎ、Ｐ、Ｋ）流失量比传统模式造林地可分别减少６６０％的水、６０８％的土壤、１０２６％的有机质流失和１０３６％的养分流失量；在造林地上间种绿肥增加地表覆盖是防治林地水土流失的有效措施之一。

The study of Chinese fir young plantation soil and water loss for five years has been observed by establishing 16 runoff plots for various means of site preparation, tending measure, interplanting green manure and silvicultural pattern. The results indicated that the order of solid runoff in over all site preparation>strip site preparation>hole site preparation, The soil runoff in hole site preparation decreased by 40.33% in solid runoff of over all site preparation, and decreased by 25.48% in solid runoff of strip site preparation. The solid erosion in different tending measure shows the explanding hole strip tending (98.695t/hm 2)>block tending (92.587t/hm 2)>bare land (4.066t/hm 2). The block tending decreased by 6.19% in soil erosion of the expanding hole strip tending. In different silvicultural pattern of young plantation, water, soil and nutrient loss all show that the traditional pattern>The World Bank type afforestation pattern>ecotype pattern. The World Bank type afforestation pattern in which loss of water, soil, organic matter and nutrient(N P K)decrease by 6.60% in liquid runoff, 6.08% in solid runoff, 10.26% in organic matter loss and 10.36% in nutrient loss of traditional pattern. It s one of the most effective measure to add to cover planting land surface to prevents soil and water loss by interplanting green manure after controlled burningin in young plantation.