The vegetation index used is the normalized difference vegetation index, green normalized vegetation index and ratio vegetation index. 采用的植被指数,包括有归一化植被指数、绿波归一化植被指数和比值植被指数。
The green biomass was converted to normalized difference vegetation index ( NDVI ) of AVHRR remote sensing, and compared with the observed NDVI from 1986 to 1990. The model was also compared with ground measurements of biomass and productivity along the transect. 模拟绿色生物量被转成AVHRR归一化植被指数(NDVI),并与1986~1990年观测到的植被指数进行了比较。
Main green vegetation in different districts and ring roads and distribution pattern of pests were analyzed using richness index, diversity index, evenness index and pest index. 运用丰富度指数、多样性指数、均匀度指数及虫情指数,分析不同区域、环线植被和害虫的分布规律。