冬小麦植被指数变化及其影响因子初探

Analysis dynamics and influence elements of winter wheat normalized difference vegetation index in mountain-foot plain

摘要: 对冬小麦植被指数(NDVI)变化规律、不同品种冬小麦植被指数差异、农田水肥状况对植被指数的影响以及植被指数与叶面积指数的关系研究结果表明，冬小麦植被指数具有日变化规律，且随冬小麦生长发育而变化，即小麦生长旺盛时植被指数数值较大。不同小麦品种植被指数表现出基本一致的季节变化特点，农田水肥条件交互影响小麦植被指数，水分胁迫时肥料对植被指数的影响明显，而水分满足时肥料对植被指数的影响不明显。

Abstract: Normalized difference vegetation index(NDⅥ)is calculated from reflectance measurements in the red-NIR of the spectrum：NDⅥ =(NIR-R)／(NIR+R)．The amount of energy reflected from a plant in the visible and near inflared portion of the spectrum has been correlated to many crop characteristics．In this paper we have measured the daily and seasona1 NDⅥ dynamics and the effects of 1eaf area index (LAI)and wheat variety on NDⅥ ．The results show that with the development of winter wheat，NDVI changes，and during daytime，from sunrise to sunset，NDⅥ changes too．There is high correlation between NDVI and LAI and different wheat varieties have different NDV1．