基于多时相遥感影像的池州市植被时空动态演化分析

Spatial and temporal dynamic Evolution of vegetation in Chi ZHOU City based on MULTi-temporal remote Sensing Image

归一化植被指数(NDVI)和植被覆盖度是作为研究植被状况的重要技术指标,因此常被用来研究区域植被的时空演化。首先下载池州市2006年—2018年的TM、OLI影像以及进行预处理操作,然后利用NDVI公式得出池州市的植被指数,利用像元二分模型得出研究区的植被覆盖度,并参照有关部门对植被覆盖度的分类标准,对池州市的植被覆盖度情况进行分类。结果表明:池州市2006年—2018年植被状况变化明显,一方面NDVI在空间上东南数值高于西北,时间上年NDVI平均值在经历下滑后逐渐稳步上升;另一方面植被覆盖度的变化较大,裸地、极低、低、中、中高植被覆盖度的面积有明显增多,高植被覆盖度的面积减少。总体来说池州市2006年—2018年的植被生物总量增多,自然环境得到明显改善。

Normalized vegetation index(NDVI)and vegetation coverage are important technical indexes for the study of vegetation conditions,so it s often used to study the temporal and spatial evolution of regional vegetation.This paper firstly downloads the TM,OLI images of Chizhou City from 2006 to 2018 and starts the pretreatment operation,then obtains the vegetation index of the Chizhou City by using the NDVI formula,and uses the pixel dichotomy model to obtain the vegetation coverage of the study area.Finally,accomplishing the classification of vegetation coverage in Chizhou City according to the classification standard of vegetation coverage by the relevant departments,the results show that the vegetation in Chizhou City from 2006 to 2108 is change obviously.On the one hand,the value of NDVI in the southeast is higher than that in the northwest in space,and the average value of the NDVI in the past year gradually increases steadily after experiencing a decline stage.On the other hand,the vegetation coverage changes greatly.There is a marked increase in the area of vegetation coverage,including bare land and Some levels of vegetation coverage(such as extremely low,low,middle,middle and high).However,the area of high vegetation coverage has been reduced.On the whole,the total vegetation biomass of Chizhou City in 2006-2018 increased,and the natural environment improved obviously.