Research On The Vegetation Cover Change Based On Wavelet Transform

Wavelet analysis is a useful method of time-frequency localization, has "mathematics microscope" and "adaptive" characteristics, its application in the analysis of vegetation cover change in the scale have obvious advantages.This paper using the wavelet transform method has analyzed the vegetation cover change, the main conclusions are as follows:(1) It was feasible to realize the expression of NDVI multi-scale and NDVI multi-scale decomposition using the wavelet transform method,and provide a new mathematical method for the vegetation cover change's research.(2) Using the multi-scale wavelet transform methods, come to reflect the inter-annual change of vegetation cover of wavelet approximate reconstruction of information and intra-annual changes during the reconstruction of the wavelet details of information.(3) The characteristics of the NDVI wavelet analysis obtained the NDVI parameters of vegetation cover change,such as, NDVI,NDVImin,△NDVI and tmax.(4) By using the wavelet variance, wavelet information entropy and wavelet energy entropy of three methods of wavelet characteristics to analysis different types of vegetation cover change, it also verify the scale of the wavelet decomposition of 4 to better reflect the characteristics of vegetation cover change.