بررسی اثر خشکسا لی بر پوشش گیاه ی با استفاده از داد ههای سنجش از دور ماهوارهای و هواشناسی)مطالعه موردی: دشت قزوین (

Plain ecosystem is highly vulnerable to environmental changes, and drought is the most famous ecosystem change driver that is difficult to identify after its occurrence. In this research study, the effect of drought on changes in vegetation changes were studied. For this, the NDVI index of MODIS images and the SPI index from 2001 to 2016 were used. The map of vegetation changes against five drought stress classes (very low classes, low, moderate, high and very high) was analysed. The results showed that across the plain vegetation changes have declined, and from east to west of Qazvin plain, the slope of vegetation changes and land susceptibility to drought have reduced. The very low drought class had the highest percentage of area in a one-month period, but at 3, 6, 9, 12, 24 and 48 months, the highest percent of the area belonged to moderate and high drought classes. The results of this study, can be used in the planning and optimal use of resources, and control changes in the future. [ABSTRACT FROM AUTHOR]