退耕还林工程对黄土高原土地利用/覆被变化的影响——以陕西省安塞县为例

doi:10.11849/zrzyxb.2011.11.006

摘要/Abstract

摘要： 退耕还林工程(Sloping land conversion program, SLCP)可快速改变土地利用/覆被格局。论文以黄土高原典型沟壑区——陕西省安塞县为例,利用MSS/TM/ETM+卫星遥感影像,获取研究区6个时期土地利用/覆被的时空信息,通过统计模型,定量分析了研究区SLCP对土地利用/覆被格局的影响。草地、耕地及林地为研究区三大主要土地利用/覆被类型,研究区土地利用/覆被变化整体处于不平衡态势;整个研究时段内,耕地先增后减,整体减少38.4%;林地先减后增,整体增加4.36%;灌木林地和草地减少,而未成林造林地快速增加;SLCP显著加强了耕地的递减趋势,并大幅增加了未成林造林地面积,至2010年未成林造林地面积显著大于天然林地的面积。这些变化可能具有降低土壤侵蚀与产流量、改善土壤结构、增加土壤碳吸收等效应;SLCP能提高农民收入,且大部分农民支持SLCP;但其负面效应亦不可忽视。研究将有助于对SLCP效应的全面理解,并可为该区生态恢复工程的规划与决策及生态环境保护提供参考。

关键词: 黄土高原, 退耕还林工程, 土地利用/覆被变化, 安塞县

Abstract: Induced by population pressure, economic growth, and historic exploitation, a large portion of China’s primary forests and wetland was depleted, and a high percentage of its farmland and grassland was degraded. These ecosystem disturbances caused extensive desertification, flooding, soil erosion, dust storms, elevated levels of greenhouse gas emissions, and severe damage to wildlife habitat. In order to address devastating environmental crises and improve human well-being, China has been undertaking several major ecological restoration efforts, of which the Sloping Land Conversion Program (SLCP) (also called Grain for Green Project) is the largest land retirement/reforestation program in the developing world, which can alter the land use/cover pattern in a considerably short time period. Here, we characterized the impacts of the SLCP on the land use/cover pattern and their consequences in Ansai County on the Loess Plateau, China, by using Landsat MSS/TM/ETM+images of six periods of 1978, 1990, 1995, 1999, 2006 and 2010. Land use/cover information was obtained using satellite remote sensing techniques. Then the impacts of SLCP on the land use/cover pattern were analyzed by the statistical models. Grassland, cultivated land and woodland were the three dominant land cover categories of the study area, and the land use/cover change was generally in unbalanced status dominated by one-way transition. In the whole research period, cultivated land declined substantially after a small increase, with an overall decreasing rate of 38.4%, woodland decreased first then followed by an increase, with an overall increasing rate of 4.36%, and shrubs together with grasslands decrease while the built-up area increased continuously. SLCP accelerated the decline trend of the cultivated land, and increased the newly forested land substantially. The area of newly forested land had significantly exceeded that of the natural forest. These changes may reduce soil erosion and water yield, restore the soil structure, and increase the soil organic matter. Most farmers support the SLCP because it can increase farmer’s net income. Nevertheless, the potential negative consequences of SLCP can never be ignored. These findings are not only useful for an integrated understanding over the impacts of SLCP, but also for the planning and decision-making of the eco-restoration projects together with the eco-environmental protection.

Key words: Loess Plateau, sloping land conversion program, land use/cover change, Ansai County

中图分类号:

F301.24

周德成, 赵淑清, 朱超. 退耕还林工程对黄土高原土地利用/覆被变化的影响——以陕西省安塞县为例[J]. 自然资源学报, 2011, 26(11): 1866-1878.

ZHOU De-cheng, ZHAO Shu-qing, ZHU Chao. Impacts of the Sloping Land Conversion Program on the Land Use/Cover Change in the Loess Plateau: A Case Study in Ansai County of Shaanxi Province, China[J]. JOURNAL OF NATURAL RESOURCES, 2011, 26(11): 1866-1878.

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