高山草地的光谱反射特征及其估产模型

A Character of Spectral Reflection and Yield Estimative Models for Alpine Meadow

对祁连山东段高山草地中５种植物群落的光谱反射特征进行了测试研究。结果表明：１）草本植物和灌木种群的光谱反射率在可见光波段上无显著差异，但在近红外波段存在显著差异；２）土壤背景和测试仪器高度对群落的光谱反射产生显著影响；３）植物生长盛期，可用近红外波段的反射差异来区分草地植物群落的空间分布：４）草地植物群落的地上植物量与几种变换的植被指数呈显著或极显著的非线性相关。

In this paper,the spectral reflectance and its affection factors,the correlation analysis between vegeta-tion index andbiomass of four het communities of alpine meadow have been studied at Tianzhu County,Gansu Province,N,W,China. The main sresults obtained are asfollows:1.There was no significant difference of spectral reflectance in 400一65 0nm,between herb and shrubcommunities. In contrast,it is great difference in 700一1050nm。2.Both soil background and measure height can affect the spectral reflection character of communitiesobviously。 3.Its practicable to classify alpine meadow communities on the basis of spectral reflectance,especiallyusing near infrared band。4.There was significant or very significant positive noh一linear correlation between vegetation indexDVI and communities biomass。Y1=-292. 61+376.74x1(x1=DVI1 comm. Elymus sp.+poa sp.- Crex sp.)Y2 = 336. 87EXP(0. 0843x2)(x2=DVI2 comm。Potygonum viviparum L. )Y3= 178.13EXP(0.1223x3)(x3=DVI3 comm。Kobresia capillifolia)5.Using comprehensive vegetation index G一Gs and ND一NDs can decrease the affection of Soil back-ground,the regression model of kgtipe artemisia community is:1/Y4=0.0028一0.0012/X4(x4=G一Gs comm。Stipa-artermista)