【摘要】 为了监测班戈县近20年(1990-2009年)草地退化状况,利用3个时相的TM和ETM数据,以及CEBERS数据,分别提取了班戈县的植被指数,并通过植被指数转化模型计算出植被覆盖度。按植被覆盖度将草地划分为4个不同退化等级,比较了班戈县近20年草地退化情况,分析了草地退化的原因。结果表明:草地退化面积前10年(1990-1999年)呈增加趋势,后10年(2000-2009年)呈减少趋势,从总体变化趋势看,草地退化面积在不断增加。造成草地退化的原因包括自然原因如气候高寒、干旱,土壤贫瘠、鼠虫害,以及人为因素如超载、不合理的开采活动以及滥挖药材等。更多还原

【Abstract】 Vegetation coverage level was calculated using vegetation index according to vegetation index transformation model.Deteriorated grasslands of Bange County were investigated using three-phase TM,TM data and CEBERS data.The deteriorated grasslands were classified as four different levels according to vegetation coverage degree.The dynamics and driving factors of grassland deterioration in recent 20 years were analyzed in Bange County.Results showed that Results showed that grasslands in Bange County were increasingly deteriorating in the last 20 years.Grassland deterioration was caused by both natural and human elements.Natural elements included frigid climate,poor soil and disaster of rats and pests,while human elements included overgrazing,irregular mining activities and excessive picking medicinal materials.更多还原