【摘要】 根据甘肃降水资料和农业气象资料分析得出 ,1 989和 1 998年为相似年景 ,利用 1 989年和 1 998年NOAA气象卫星AVHRR资料 ,计算分析了 1 0a来河西绿洲植被面积和植被指数等级的变化。分析结果表明 ,1 0a来河西绿洲面积呈增加趋势 ,各绿洲植被指数有不同程度的增加。更多还原

【Abstract】 The precipitation and agricultural meteorological data of 1989 and 1998 are analysed.By using the data of the NOAA meteorological satellite data of AVHRR in 1989 and 1998, calculation and analysis were carried out to study the change in the oasis area and vegetation indexes in Hexi during the past ten years. The results show that oasis area in Hexi is increasing, and that vegetation indexes for all the oasis areas have increased in various degree.更多还原