陕南秦巴山区退耕还林与可持续发展研究——改汉中市为例

汉中市位于陕南秦巴山区，是南水北调中线工程的重要水源地，长期以来水土流失严重。根据汉中市水土流失情况，以生态优先、综合治理原则，确定了四个重点退耕区。实施退耕还林工程。汉中市植被覆盖增加，水土流失得到治理，生态环境改善。通过分析退耕还林使耕地面积减少，粮食总产量下降，但汉中并不存在粮食安全问题。退耕还林促使土地利用结构发生改变。农业产业结构调整，农业总产值增长。通过退耕还林，汉中市实现生态、经济和社会的可持续发展。

Research of Converting Cropland to Forest and Grassland and Sustainable Development in Qingling-Bashan Mountains --An Example From Hanzhong City

Hanzhong city lies in Qingling-Bashan mountains,as the important fountainheads of South-North Water Diversion centre line project, soil erosion in Hanzhong city is serious for a long time. According to soil erosion situation, with ecology preferential and comprehensive administration principle, are confirmed four emphasis areas. Through converting cropland to forest and grassland, the vegetation is increased, soil erosion is controlled, ecological environmental is improved. The cropland decrease and grain total output drop because of converting cropland to forest and grassland, it will not intimidate the grain security in Hanzhong city. The converting cropland to forest and grassland impels the land use pattern change, agricultural structure adjustment and agricultural gross output value increase. Hanzhong city realizes the sustainable development of ecology,economy and society by converting cropland to forest and grassland.