Inversion of a Radiative Transfer Model for Estimation of Rice Canopy Chlorophyll Content Using a Lookup-Table Approach
Inversion of a Radiative Transfer Model for Estimation of Rice Canopy Chlorophyll Content Using a Lookup-Table Approach
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DOI：
10.1109/jstars.2012.2186118
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发表时间：
2012-08-01
影响因子：
5.5
通讯作者：
Ahangar, Abdolhamid Dashti
中科院分区：
文献类型：
--
作者：
Darvishzadeh, Roshanak;Matkan, Ali A.;Ahangar, Abdolhamid Dashti
光学遥感提供了关于重要植被变量的信息，如叶面积指数、生物量和叶绿素含量。在这项研究中，水稻作物，这是很少研究，选择，因为它们的高度经济重要性和它们在研究区域的粮食安全中发挥的作用。其目的是获得一个可靠的估计冠层叶绿素含量作为一个重要的指标，用于评价植物的状态。采用PROSAIL辐射传输模型和ALOS AVNIR-2卫星多光谱图像数据。2010年7月在伊朗北方地区阿莫尔开展了一次实地活动。随机选择60块20 x 20 m（2）的样地，使用SPAD-502叶绿素仪测量其叶绿素含量。使用查找表（LUT）方法对PROSAIL进行倒置。LUT以不同的大小生成。利用方差分析（ANOVA）研究了LUT大小对冠层叶绿素含量反演精度的影响。反演的结果进行了评价，使用计算的R-2和RMSE值与现场测量。所获得的结果表明，PROSAIL有能力利用ALOS AVNIR-2多光谱数据估算水稻植株叶绿素含量（R-2 = 0.65; RMSE = 0.45）。结果还证实了这种方法在作物监测和生态应用方面的有用性。
Optical remote sensing provides information on important vegetation variables such as leaf area index (LAI), biomass, and chlorophyll content. In this study, rice crops, which are rarely studied, were selected because of their high economic importance and the role they play in food security in the study area. The aim was to obtain a reliable estimate of canopy chlorophyll content as an important indicator for the evaluation of the plant status. PROSAIL radiative transfer model and the multispectral image data of ALOS AVNIR-2 were used. A field campaign was carried out in July 2010 in the northern part of Iran, Amol. Sixty sample plots of 20 x 20 m(2) were randomly selected, and their chlorophyll content was measured using a SPAD-502 chlorophyll meter. The PROSAIL was inverted using a lookup-table (LUT) approach. The LUTs were generated in different sizes. The effect of the LUT size on the retrieval accuracy of the canopy's chlorophyll content was studied using analysis of variance (ANOVA). The outcome of the inversion was evaluated using the calculated R-2 and RMSE values with the field measurements. The obtained results demonstrate the ability of PROSAIL to estimate rice plant chlorophyll content using ALOS AVNIR-2 multispectral data (R-2 = 0.65; RMSE = 0.45). The results also confirmed the usefulness of such an approach for crop monitoring and ecological applications.