Analysis on Vegetation Change in Zoige Region by the Scale Transformation Method Based on MODIS and NOAA DATA
In order to obtain a longer time series vegetation index in Zoige Plateau Wetland,spatial conversion and time extrapolation of GIMMS NDVI and MODIS NDVI were obtained by the method of image resampling and unitary linearity regression.The results showed that:(1) spatial scale was related to the influence of resampling methods for MODIS NDVI data,while it was hardly related to the GIMMS NDVI resampling data;(2) at 2.5 km per pixel resolution,the regression equation of different vegetation types between the two kinds of data was set up,the difference between the fitting results by GIMMS NDVI and MODIS NDVI conformed to normal distribution;(3) from 1982 to 2013,the vegetation in the study area degraded before gradual recovery,and the year of 1998 was the turning point,although the average level of vegetation index was higher than that in the early 1980s,local vegetation degradation situation was still serious.
GIMMS NDVIMODIS NDVIresamplingmonadic linear regressionZoige Plateau Wetland