摘要
利用1987、2000、2008年民勤县TM遥感影像数据,基于GIS技术和统计分析方法,分析民勤县土地利用/覆被生态风险的时空特点和结构演变,并选取土地利用综合指数和景观格局指数研究土地利用变化对土地生态系统造成的风险进行评价。结果表明:民勤县土地利用/覆被存在的生态风险主要集中在草地和未利用地,两者的面积占研究区总面积的75%以上。耕地、草地、未利用地三种土地类型间的相互转化是民勤县22年间最主要的土地利用变化。在人类活动对土地的扰动作用日益加强和区域经济社会发展目标趋同性的双重影响下,土地利用的广度和深度上不断增大,研究区斑块数量明显增多,景观破碎化程度加重,景观多样性指数和分形维数指数上升,土地生态风险程度增大。
Based on the TM remote sensing images as well as the field survey data, the characteristics of quantity and spatial changes of Minqin County were analyzed in 1987, 2000 and 2008 by GIS and statistics methods, in order to explore the ecological risks with land-use composite index and landscape pattern index. It is suggested that the ecological risk of land-use cover in Minqin County was mainly concentrated in the grass land and unused land which accounting for the ratio between the total area of more than 75%. The transformation between three land types including cultivated land, grass land and unused land was the most striking land use change in Minqin County during 22 years. With the impact of increasing intensity of human activities and development of regional economy, the eco-environment in the study area was very vulnerable to the land use change, resulting in increasing of the number of plaques, landscape fragmentation, diversity index and fractal dimension index, which obviously increases land ecological risk.
出处
《土壤通报》
CAS
CSCD
北大核心
2012年第5期1029-1035,共7页
Chinese Journal of Soil Science
基金
国家自然科学基金项目(40971078)
甘肃省青年科技基金计划项目(1107RJYA077)
西北师范大学青年教师科研能力提升计划项目(SKQNYB10034)资助
