湘中地区地级市植被覆盖变化多尺度分析

Multi-scale analysis of vegetation cover changes in central Hunan region

归一化植被指数(NDVI)作为一种植被指数,其数据集合在一定程度上可以反映区域的植被覆盖变化情况,是监测生态环境变化的一项重要指标。本文以湘中地区XT市为研究区域,以250 m空间分辨率的NDVI数据集作为数据源,采用一元线性回归方法和相关系数方法,从省、市、县3个尺度对比分析不同尺度的植被覆盖变化,为不同尺度上的宏观生态政策制定提供参考。结果表明,研究区大部分区域植被覆盖呈明显增加趋势;市、县区植被覆盖增长速率低于全省年均增长率,且XT市、XX市和SS市植被覆盖呈明显增长趋势。

As a planting index,NDVI data set can reflect the changes of regional vegetation coverage to a certain extent,which is an important index to monitor the change of ecological environment.In this paper,the NDVI dataset with a resolution of 250 m was used as the data source,and the unitary linear regression method and correlation coefficient method were used to conduct comparative analysis from the vegetation cover of the central Hunan region(XT),and the vegetation change at different scales was analyzed from the three scales of the province,city and county.It provides reference for the formulation of macro-ecological policies on different scales.The results showed that the vegetation in most areas of the region showed a significant increase trend.Compared with the average annual growth rate of the whole province,the vegetation cover growth rate of XT City was lower than the average annual growth rate of the province,and the vegetation cover of XT and XX and SS City showed a significant growth trend.