用冠层高光谱反射估测玉米植株色素时的采样点和指标选择  

Selection of sampling sites and pigment parameters in estimating plant pigment status by canopy hyperspectral reflectance in corn plants

作　　者：谢瑞芝[1] 周顺利[2] 王纪华 蒋海荣[2] 

机构地区：[1]中国农业科学院作物科学研究所,北京100081 [2]中国农业大学农学与生物技术学院,北京100094 [3]国家农业信息化工程技术研究中心,北京100089

出　　处：《农业工程学报》2006年第4期135-138,共4页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家863项目(2002AA243011);北京市科技项目(H010710010123)资助

摘　　要：初步分析了11个玉米品种在7个生育期的植株叶绿素含量、类胡萝卜素含量和叶绿素/类胡萝卜素比值在不同层位(上层、中层和下层)的变化特点及其与15个高光谱参量间的关系,结果发现1)玉米叶片叶绿素/类胡萝卜素比值较明显表现出随形态学高度的下降而升高;2)绝大多数的高光谱参量与叶绿素含量(m g.g-1FW)间达到了显著或极显著相关,但相关性不强(最大r=0.56,n=77);3)高光谱参量与叶绿素/类胡萝卜素比值间相关性,明显强于与叶绿素含量或类胡萝卜素含量间的相关性(最大r=0.75,n=77),并表现出明显的层间差异,下层明显强于中层和上层。研究表明,在用高光谱反射分析玉米的色素状况时,用叶绿素/类胡萝卜素比值代替叶绿素含量作为色素指标可提高分析精度。The leaf chlorophyll content, carotenoid content and chlorophyll/carotenoid ratio were investigated in relation to fifteen hyperspectral vegetation indices at different layers （upper, middle and low） of the corn plants in a field experiment. The chlorophyll/carotenoid （Chl/Car） ratio appeared to increase with the morphological height decreasing. The hyperspectral variables were significantly related to the leaf chlorophyll content（mg · g^-1 FW）with the highest coefficient of 0. 56 （n = 77） yielded, while they were better correlated to the leaf chlorophyll/carotenoid ratio with the highest coefficient of 0. 75 （n = 77） yielded. The chlorophyll/carotenoid ratio at the low layer was better correlated with the spectral indices than that at the upper layer or at the middle layer. The results suggested that the accuracy could be improved by using the Chl/Car ratio as the pigment parameter when estimating the pigment status in the corn plants by hyperspectral reflectance.

关 键 词：玉米 高光谱反射 色素 叶绿素/类胡萝卜素比值 层间变异 

分 类 号：O433.1[机械工程—光学工程] O434.13[理学—光学]