A comparison of hyperspectral chlorophyll indices for wheat crop chlorophyll content estimation using laboratory reflectance measurements
A comparison of hyperspectral chlorophyll indices for wheat crop chlorophyll content estimation using laboratory reflectance measurements
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DOI：
10.1109/tgrs.2007.897429
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发表时间：
2007-10-01
影响因子：
8.2
通讯作者：
Schwarz, John W.
中科院分区：
文献类型：
--
作者：
Bannari, Abderrazak;Khurshid, K. Shahid;Schwarz, John W.
本文的目的是调查之间的关系，利用实验室测量的各种高光谱叶绿素指数和小麦作物叶绿素含量。这些测量包括格尔-3700分光辐射计数据、使用土壤-植物分析开发（SPAD）-502仪的叶片叶绿素含量和通过化学实验室分析估算的叶片叶绿素含量。将SPAD-502测量值与实验室提取的叶片叶绿素含量进行相关分析，建立了计算叶绿素ab（Chl-ab）和叶绿素a（Chl-a）含量的校正方程。这导致Chl-ab含量和Chl-a含量的决定系数（R-2）分别为0.72和0.69，均方根误差（RMSE）分别为3.53和1.94 μ g/cm（2）。这些估计被用来建立高光谱叶绿素指数从格尔-3700数据计算的关系。从所调查的指标来看，NPCI的结果最好，R-2为0.84，RMSE为11.0。其他指标如GNDVI、OSAVI、PSSRa、PSNDa、CAI、HNDVI和MTCI的表现不令人满意。较好的指标是NDPI、SIPI、PRI和SRPI，其R-2分别为0.56、0.62、0.54和0.57，RMSE分别为11.06、10.27、11.32和10.96 μ g/cm（2），但与叶绿素含量的相关性较弱。
The objective of this paper is to investigate the relationship between a wide range of hyperspectral chlorophyll indices and wheat crop chlorophyll content using laboratory measurements. These measurements included the GER-3700 spectroradiometric data, leaf chlorophyll content using the Soil-Plant Analyses Development (SPAD)-502 meter and leaf chlorophyll content estimated from chemical laboratory analysis. The SPAD-502 readings were correlated with leaf chlorophyll content extracted in the laboratory to establish calibration equations for the computation of chlorophyll-ab (Chl-ab) and cblorophyll-a (Chl-a) content. This resulted in a coefficient of determination (R-2) of 0.72 for the Chl-ab content and 0.69 for the Chl-a content and a root mean square error (RMSE) of 3.53 and 1.94 mu g/cm(2), respectively. These estimates were used to establish relationships against hyperspectral chlorophyll indices calculated from the GER-3700 data. From the investigated indices, the NPCI showed the best results with R-2 of 0.84 and RMSE of 11.0. The other indices, such as GNDVI, OSAVI, PSSRa, PSNDa, CAI, HNDVI, and MTCI did not perform satisfactorily. The better ones, but still showing a relatively week relationship with leaf chlorophyll content, are the indices NDPI, SIPI, PRI and SRPI with R-2's of 0.56, 0.62, 0.54, and 0.57, respectively and RMSEs of 11.06, 10.27, 11.32, and 10.96 mu g/cm(2), respectively.