Variation of NDVI and the Relationship with the Change of Climate in Zhengzhou of China

摘要

Based on 1982-1999 satellite sensings, meteorological data and observations of crop growth/development, a study is conducted on seasonal and interannual variations in vegetation NDVI (normalized difference vegetation index), its response to climate change and its relationship with crop growth/development during the period in Zhengzhou region of Henan province. Evidence suggests that the interannual change is not so pronounced in the regional NDVI, exhibiting, on the whole, an unsteadily increasing trend; stronger seasonally is shown in the annual variation, with a more significant rising trend in spring as opposed to those for summer and autumn; NDVI change is in positive correlation both to temperature and precipitation (stronger response to temperature), with its change subject dominantly to temperature and rainfall in spring and summer, respectively, under varying effect of temperature and precipitation in autumn, and largely under the impacts of heat in winter and during the growth of winter wheat and summer-sown corn the NDVI is positively correlated to the crop height and density (the number of crop individuals per unit area) in their milking stage, the latter acting as a principal factor of NDVI change.