基于PROSPECT-D的铜胁迫下小麦叶片光谱辐射传输模型构建

针对铜胁迫下的小麦叶片光谱反射率与叶片铜元素含量之间的物理模型定量关系这一科学问题，本项目依托PROSPECT模型的最新版本PROSPECT-D，利用实测的光谱反射率和透射率数据，构建铜胁迫下小麦叶片的光谱辐射传输模型。主要研究内容包括：（1）研究铜胁迫下小麦的叶片结构参数反演，阐明小麦叶片结构参数随铜胁迫程度的变化规律；（2）研究各个生化组分吸收系数在不同波长的数值反演，揭示各个生化组分吸收系数曲线的特征规律，并初步探究其机理解释；（3）从正演和反演两个方面研究模型的精度水平，并实现模型的优化。最终，形成铜胁迫下小麦的叶片光谱反射率与铜元素含量之间的物理模型定量关系。本项目成果将有助于认清铜胁迫下小麦光谱特征变化的规律及其背后的主控因素，为提升高光谱遥感反演小麦叶片铜元素含量的能力和通用性提供物理模型基础，对我国粮食安全保障和环境重金属铜污染监测具有重要的科学意义和应用前景。

To solve the scientific problem on the physical quantitative relationship between spectral reflectance and copper content of wheat leaves under copper stress, this project is to establish a spectral radiative transfer model of copper-stressed wheat leaves based on the latest version PROSPECT-D of PROSPECT model using measured spectral reflectance and transmittance. The main research contents include: (1) This project is to investigate the retrieval of leaf structure parameters of copper-stressed wheat leaves and to clarify the changing pattern of leaf structure parameter with copper stress level. (2) The specific absorption coefficient (SAC) of biochemical constituents at different wavelengths is to be investigated with numerical inversion. The feature and pattern of SAC curves are to be revealed and its explanatory mechanism is to be preliminarily explored. (3) The accuracy level is to be evaluated by both forward simulation and back forward parameters retrieval, and the model is to be optimized. The final results of this project are to form the physical quantitative relationship between reflectance and copper content of copper-stressed wheat leaves. The achievements of this project will contribute to recognizing the changing pattern of spectral features and its controlling factors of copper-stressed wheat leaves, and provide the physical model foundation for improving the inversion ability and generality of copper content in wheat leaves using hyperspectral remote sensing. This project shows important scientific significance and application prospect for protecting food security and monitoring the environmental heavy-metal (copper) pollution.