摘要
在黄河流域的黄土高原地区,其沟谷部位陡峭、破碎,水土流失严重,虽不利于农业生产,但具有林草发展优势,林木生长快,其生长量比相对干旱的梁、峁和坡面快很多,因而发展林木,郁闭快,经济、生态效益好, 沟谷部位水土流失量大,洪水为高含沙水流,下切、冲刷严重,而林木及草减缓流速,削减洪峰、洪量,固土作用大,能起到显著的减沙效果,人工林治理的杨家沟,其林地面积为流域面积的40％,因主要集中沟谷,而减沙效果达92.6％之多;而且在特大暴雨中能同样发挥减沙作用, 通过实地考察和分析,提出在综合治理的同时,平行不悖的在沟谷营造速生密植林,这样能更快、更有效地防治水土流失,提高经济效益,有利治黄事业,
On the loess plateau of the Yellow River basin, the landscape is intensively dissected by steep gullies. The loss of soil and water caused by gully erosion is serious. The gullies, although unfavourable for agricultural development, are good places for planting trees and grasses. Trees and grasses grow several times faster in the gullies than on the relatively dry ridge summits and slopes, and give better economic yields. The loss of soil and water from the gully systems is very high, the sediment concentrations of flood water can be very high, and scouring may be a serious problem. In view of their capability to reduce flow velocities and volumes and flood peaks and their soil binding properties, trees and grasses have proved very effective in reducing sediment , loads. The man-made forests established in Yangjiagou, with forest cover of 40% mainly growing in the gullies, have reduced sediment yields by as much as 9 2.6%,’even’ during storms. Through site investigations and analyses, we suggest planting fast growing trees at a high density linked with comprehensive imp rovement. In this way, we can effectively control soil erosion and produce greater economic benefit.
出处
《泥沙研究》
CSCD
北大核心
1994年第1期14-21,共页
Journal of Sediment Research
