祁连山北坡退化水源涵养林生态修复模式研究

祁连山水源涵养林对西北干旱区降水调节、涵养水源、保持水土、改善气候发挥着重要作用。通过对祁连山北坡不同类型林地进行调查研究,结果表明:毁林耕种致使中山区的90%水源涵养林林缘都受到破坏,10%的森林中有面积超过30m×30m的较大林窗。采用坡地鱼鳞坑和坡脚水平沟营造青海云杉和祁连圆柏,形成坡面流水收集,坡底沟缘"锁"边的水源涵养林恢复体系。鱼鳞坑增加表层土壤蓄水力,水平沟则增加了20~40cm土层含水量,而林窗的土壤受干扰则增加了40cm土层含水量。人工造林增加了植被盖度,提高了土壤蓄水量,减少水土流失,增加水源涵养能力。根据立地类型,将封山育林、造林和水土保持工程结合是有效的退化涵养林恢复措施。

Ecological Restoration Mode of Qilian Mountain Northern Slop Degraded Water Conservation Forest

Qilian Mountain water conservation forest plays an important role in rainfall regulation,water conserva-tion,soil preservation and climate improvement.After investigation for different types of forest in the northern slope,the results showed that 90 % of water conservation forest edge in the middle mountains was destroyed by farming,and 10 % forest had more than 30×30 m forest gap.A recover system was build up by slope running wa-ter collecting and gully edge locking in Picea crassifolia and Sabina przewalskii planted area with slope fish-scale pit and level ditches.Surface soil conservation was increased in slope fish-scale pit,with 20-40 cm depth soil water content,and 40 cm depth in forest edge.Plantation promotes vegetation cover,water content and decreases water and soil loss.Combination of enclose hillsides for afforestation and soil and water conservation project is an effective way for degraded water conservation forest recovery.