许昌植被状况的MODIS产品评价

Evaluation of Vegetation Status by Using MODIS Products in Xuchang

为分析许昌市植被状况,选择MODIS产品反演该地区NDVI、NPP和LAI三种指示植被状况的指数,对许昌市2013—2017年植被生长状况的时空变化进行研究.研究结果表明,许昌市总体植被状况从2013—2017年得到较好的改善.NDVI、NPP和LAI三种指数均呈现以2015年为极大值点的“下降-上升-下降-上升”单峰趋势.MODIS产品反演得到的NDVI和LAI均呈现较明显的季节变化规律,而NPP无明显季节变化规律.2013—2017年许昌市各地区中,魏都区植被生长状况整体在快速优化三种指数值分别为0.52,271.5和290,禹州市植被生长状况始终较差三种指数值分别为0.72,219.5和176,而其他地区差别不大.

Vegetation condition is an important indicator for regional eco-environmental quality evaluation.The NDVI,NPP and LAI are acquired from MODIS products to study the vegetation growth status from 2013 to 2017 in Xuchang.The results show that:the vegetation growth status of Xuchang improved continually from 2013 to 2017.NDVI,NPP and LAI showed the“up-down-up-down”fluctuation trend with the maximum point appeared in 2015.The NDVI and LAI both changed regularly with the change of the season,but there wasn’t a seasonal characteristic on NPP.The vegetation condition in Weidu District achieved rapid improvements with the values of 0.52,271.5 and 290 in terms of three rapid optimization indexes,while that in Yuzhou was poor and the value were 0.72,219.5 and 176,the regional difference of the other areas were not quite big.