Comparison of 3 NDVI Datasets and the Application at Yanhe Basin, China
The paper compared consistency and difference among the NDVI datasets of GIMMS 、SPOT VGT and MODIS in Yanhe Basin,China.The available overlapping data in 2000-2006 were used to compare their consistency.The comparison was done through consistency and correlation coefficients.It was shown that the SPOT VGT NDVI was significantly correlated with the MODIS NDVI.However,there were some differences between the GIMMS NDVI and SPOT VGT/MODIS NDVI.As the only dataset which contains more than 30 years data,the GIMMS NDVI is irreplaceable in analyzing the long-term change of the vegetation.Thus,the GIMMS NDVI should be regulated in accordance with the other two,which are considered more precise in reflecting the vegetation coverage.It was found that GIMMS NDVI was more closely correlated with SPOT VGT NDVI in July and September than in August in Yanhe River Basin.Therefore,a revision method of the GIMMS NDVI was proposed and was applied in the Yanhe Basin at different spatial scales,which were the whole basin,the sub-basin,and the pixel scale.The results indicate that the GIMMS NDVI of different spatial scales could be revised effectively while the vegetation coverage is low,and the revised GIMMS NDVI shows good consistency with the SPOT VGT NDVI and MODIS NDVI.However,the revise method doesn't work very well in the high vegetation conditions,which required further research.
NETL
NSTL
万方数据
维普
