西藏“一江两河”中部地区的农业发展与农田沙漠化

Agricultural Development and Farmland Desertification in Middle "One River and Its Two Branches" River Basin of Tibet

一江两河"中部地区是西藏农业生产的主要区域,也是沙漠化土地最集中、危害最严重的区域之一。作者分析了区域内农业开发、农业耕作制度改变和土壤肥力变化对农田风蚀的影响,初步得出:盲目开垦、不合理的农作制度和薄弱的农田基础条件加剧了农田沙漠化的发生、发展,造成目前区域内约5万hm2占区域内总耕地面积47%以上的农田遭受风沙危害,并呈扩展态势。为了有效的防治农田沙漠化的发生、发展,建议加强农田防护林等基础建设,大力发展草田间作、草田轮作等草地农业模式,建立适宜的传统农作与现代技术结合、经济效益与生态效益结合的农作制度,扩大冬小麦、冬青稞、油菜和豆科作物、豆科饲料等冬春季节覆盖农田地表的作物面积。

The middle !One River and Its Two Branches' river basin area is the largest agriculture region and also is one of most seriously desertified regions in Tibet. The agricultural development in this region was hindered by wind erosion of farmland soil. In this paper, the impacts of reclamation, farming system change and soil fertility variation on wind erosion of farmland soil were analyzed. The result showed that blind reclamation, unreasonable farming system and weak agricultural basic construction have aggravated the farmland desertification. At present, over {50 000} hectares farmlands suffer from wind erosion, which occupied 47 percent of the total farmland area in the region and the ratio tends to enlarge. For controlling wind erosion in farmland, it is suggested to strengthen the basic construction of farmland, as such shelter belt, irrigation installation and so on must be perfect; to largely adopt intercropping or rotation of crop with herbage. The suitable farming system that combined modern farming system with conventional farming system and economy benefit with ecology benefit should be established. In details, the crop area that covers soil in winter and spring such as winter wheat, winter barley, rape, bean crop and bean forage should be enlarged.