对水稻微分光谱和植被指数的探讨

通过不同供氮水平的田间试验，分析了微分光谱对消除水稻冠层光谱的背景影响和植被指数在农学参数测定中的作用。结果表明：由微分光谱所得的红边位置、红边斜率与盖度、叶面积指数及供氮水平之间有一定的相关性；水稻多光谱植被指数RVI、NDVI与叶面积指数LAI及其地上部生物量之间有极显著相关性；高光谱植被指数及其变量与植被盖度、供氮水平之间存在相关性。这些表明，用微分光谱技术与植被指数方法监测水稻的田间供氮水平和长势似乎是可行的。

Approach the Derivative Spectra and Vegetation Indices of Rice

B y field tests of rice in different nitrogen levels ,we analyse the action o f derivative spectra on eliminating background influen ce on rice canopy spectra and that of vegetation indices on determ ining agricul tural parameters.The result shows that there are a certain correlations between the p osition and slope of red edge of canop y spectral reflectance of rice and fr actional vegetation cover,leaf area index(LAI )and nitrogen supply level .The multiple spectral vegetation indices RVI and NDVI of rice canopy are remar kabl e correlative with LAI and above ground matter,but the hyperspectral vege tation index and its variable are a certain correlative with rice fractional cov er and nitrogen s upply level.This proves that it is fe asible for using the te chnology of derivative spectrum and method of vegetation index to monito r the n itrogen supply level and growi ng of rice.