采用小区实验与大田应用相结合的方法, 依据扬州实验小区地面实测拔节期、抽穗期及灌浆期的水稻叶片、冠层光谱及氮和叶绿素含量, 采用光谱吸收特征和植被指数分析方法, 得到估算水稻氮和叶绿素含量的最佳光谱特征参数; 结合覆盖江苏姜堰地区大田的Hyperion高光谱遥感影像, 建立反演水稻冠层氮和叶绿素含量的模型, 对研究区大田水稻冠层氮和叶绿素含量进行了反演及制图。结果表明: 经波深中心归一化方法分析, 发现以670nm为中心的光谱吸收特征面积与水稻氮含量呈显著相关性; 基于反转归一化光谱, 结合560nm和670nm两个波段, 建立的植被指数NDVI560_670能很好地反演水稻叶绿素含量。

The method of plot experiment with field application was used in this research. The variations of rice foliage and canopy spectra with corresponding biochemical concentration field-measured in jointing, heading and filling stages were analyzed. Through the analysis of absorption characteristic and vegetation index, the best spectral features for rice nitrogen and chlorophyll concentration estimation were obtained. Based on the Hyperion image of Jiangyan, we built the models of rice canopy nitrogen and chlorophyll estimation. At last, rice canopy nitrogen and chlorophyll concentration were retrieved from Hyperion image and their distribution maps were obtained. The results showed that: (1) Nitrogen concentration can be retrieved accurately using the area of absorption feature centered at 670nm based on band depth normalized to band depth (BNC) analysis; (2) Based on reversional normalized spectrum, NDVI using 560nm and 670nm was strongly correlated with chlorophyll concentration.