宁夏固原地区山坡地的水分再分配与退耕还林问题

宁夏固原地区是我国水土流失最为严重的地区之一。在进行坡耕地退耕还林还草时，应根据土壤的物理特性和山坡地水分再分配的特点，在山顶和山坡，建立以灌木和草类植物为主组成的人工植被；在水分条件较好的沟谷地带，适量建立一定面积以乔木为主的植被。

Issue on Water Distribution of Hill Land and Return Crop Spots to Forestry in Guyuan District of Ningxia

Abstract: Guyuan district in Ningxia is one of the most severe regions that subject from soil and water lossin China. The key measure of controlling soil and water erosion is returning hill crop spots to forestry. Inpractice, it is essential to take soil physical property and hill farmland water distribution into considera-tion. For exampled, artificial vegetation dominated by shrubs and grasses must be constructed on the topand the slop of hill, and plantation dominated by arbores should be established in the valley with good wa-ter condion.