用冠层反射光谱预测小麦叶片糖氮量及糖氮比  

Monitoring Soluble Sugar, Total Nitrogen & Its Ratio in Wheat Leaves with Canopy Spectral Reflectance

作　　者：田永超[1] 朱艳[1] 曹卫星[1] 

机构地区：[1]江苏省信息农业高技术研究重点实验室,江苏南京210095

出　　处：《作物学报》2005年第3期355-360,共6页Acta Agronomica Sinica

基　　金：国家自然科学基金重点 (3 0 0 3 0 0 90 ) ;国家"863"计划 (2 0 0 2AA2 43 0 11) ;江苏省自然科学基金 (BK2 0 0 3 0 79) ;高校博士点基金(2 0 0 3 0 3 0 70 17)资助项目。

摘　　要：在不同土壤水氮条件下,研究了小麦中后期叶片碳氮状况及其比例与冠层光谱反射特征的关系。结果表明,叶片可溶性糖含量和积累量均随比值指数R(6 6 0 ,4 6 0 )的增加而降低,呈极显著负指数相关,而与其他植被指数相关不显著;叶片氮含量和氮积累量分别与比值指数R(95 0 ,710 )和R(95 0 ,5 6 0 )呈极显著正直线相关。发现小麦叶片糖氮比与所有比值、归一化和差值形式的植被指数相关均不显著,但与绿度调节植被指数(GSAVI)具有良好的相关性,呈极显著二次抛物线关系,模型的检验误差为0. 11,预测值和实测值的决定系数R2 为0 . 85。因此,绿度调节植被指数可用来评估小麦叶片糖氮比状况。The research was conducted to determine the relationships of sugar and nitrogen status and its ratio in wheat leaves to canopy spectral reflectance under different nitrogen and water supply levels. The results showed that there were negative exponential relationships of soluble sugar content and accumulation to ratio index R(660,460), but no significant relationships with other vegetation indices; and there were positive linear relationships of leaf nitrogen content and accumulation to ratio index R(950,710) and R(950,560) in wheat leaves. In addition, green soil-adjusted vegetation index (GSAVI) was found to be parabolically related with sugar to nitrogen ratio (S/N) in wheat leaves, with the RMSE of 0.11 for model testing, although no significant correlations were found between S/N and other vegetation indices, such as ratio index, normalized index and difference index. The present results indicate that the GSAVI should be a good indicator to evaluate leaf S/N ratio in wheat.

关 键 词：小麦 反射光谱 植被指数 叶片糖 叶片氮 糖氮比 

分 类 号：S512.1[农业科学—作物学]