Normalized difference vegetation index dynamic and spatiotemporal distribution of migratory birds in the Poyang Lake wetland, China

Our results show: (1) The inter-annual NDVI shows an uneven yet increasing trend since 2000, with the average NDVI ranging between 0.17 and 0.64. Its seasonal change is roughly in line with the seasonal variability of natural vegetative growth in the area. (2) Both the number of species present and the population of migratory birds show an increasing trend, and avian biodiversity has greatly increased. In most years herbivorous birds dominated over other foraging guilds. (3) The correlation between NDVI variability and bird population, usually above 0.5 in typical reservation zones, differs in reservation zones and for foraging guilds of migratory birds. NDVI was significantly correlated with the population of herbivorous birds. (4) Land-use types can influence this correlation through its reflection of different NDVIs. Wetland is positively correlated with bird population of all species, while cropland is negatively correlated.