基于辐射传输模型滨海湿地翅碱蓬植被的花青素高光谱反演

Estimation of biophysical and biochemical vegetation parameters using the field measure spectral data is a research hotspot in hyperspectral remote sensing. Salt marsh plant Suaeda Heteroptera of coastal wetland has very high economic value and ecology value. Retrieval of Suaeda Heteroptera’s anthocyanin content is important significance for nondestructive monitoring Suaeda Heteroptera’s developmental stage and growing status. It also plays an important role in monitoring and advanced warning for ecological environment of salt marsh wetland. This project intends to research hyperspectral quantitative inversion models of anthocyanin content for Suaeda Heteroptera in Panjin coastal wetland, based on field measure spectral data. Based on experiments, this work will analyze the spectral reflective characteristic and response feature of Suaeda Heteroptera's anthocyanin content.Then, studying Suaeda Heteroptera’s leaf radiative transfer model and the coupled leaf-canopy radiative transfer model based on Suaeda Heteroptera’s special morphological structure and biochemical at different scales (leaf scale and canopy scale). Finally, at canopy scale,building the Suaeda Heteroptera’s anthocyanin quantitative inversion model based on the established model, and studying the model inversion algorithm,to explore a new method to retrieval anthocyanin content based on the physical mechanism.This research will enrich the basic theories on vegetation radiative transfer model of the different spatial scales, promote the development of plant’s anthocyanin quantitative inversion study and provide the research basis for estimating Suaeda Heteroptera’s anthocyanin inversely at pixel scale in future. This research will also provide a new information acquisition means for other research fields, such as environmental science and biological science.

估算植被理化参数是高光谱遥感的研究热点。花青素是具有极高经济、生态价值的盐沼植被翅碱蓬的主要色素，反演其含量对监测翅碱蓬植被的发育阶段和生长状态有着重要意义，也会对盐沼湿地生态环境起到监测和预警的作用。本项目将以盘锦滨海湿地内的翅碱蓬为研究对象，以有效反演盐沼植被翅碱蓬花青素含量为基本目标，研究翅碱蓬叶片、冠层结构及生化组分特征，分析翅碱蓬花青素高光谱响应机理，研究发展适合翅碱蓬的叶片辐射传输模型和叶片-冠层辐射传输耦合模型；并基于所建立模型，研究冠层尺度下叶片花青素定量反演模型，探求具有物理机制的精确、高效、快捷估算花青素含量的高光谱遥感方法。本研究将丰富叶片、冠层尺度下特殊形态和生化组分的植被辐射传输模型的研究，将推进植物花青素含量高光谱遥感反演研究的发展，为今后能够在像元尺度上进行翅碱蓬花青素含量的反演提供研究基础，同时也将为环境科学、生物科学等其他研究领域提供一种新的信息获取手段。

估算植被理化参数是高光谱遥感的研究热点。花青素是具有极高经济、生态价值的盐沼植被盐地碱蓬的主要色素，本项目主要针对从物理模型角度构建盐地碱蓬的花青素地面定量反演模型中所面临的相关问题展开研究，反演其含量对监测盐地的发育阶段和生长状态有着重要意义，也会对盐沼湿地生态环境起到监测和预警的作用。本研究首先基于PROSPECT-D模型，利用迭代数值优化算法对模型中的各生化参数的特定吸收系数进行校准，并通过盐地碱蓬叶片样本实测的反射光谱数据对校准后模型进行性能验证，最终证明了校准优化后模型的有效性。其次采用代价函数迭代优化SAIL模型Campbell椭球叶倾角分布函数多项式系数，并引入叶片反射率与透射率比例系数kr、kt，进而构建了叶倾角-比例系数双参数模型盐地碱蓬群落SAIL冠层辐射传输模型。最后基于优化后的叶片-冠层尺度耦合模型模拟不同花青素含量及叶面积指数值的冠层反射光谱，优选出合适的植被指数Vogelmann2，并构建了花青素含量线性反演模型。此外增加了盐地碱蓬群落DART模拟模型相关研究。本研究将丰富叶片、冠层尺度下特殊形态和生化组分的植被辐射传输模型的研究，将推进植物花青素含量高光谱遥感反演研究的发展，为今后能够在像元尺度上进行盐地碱蓬花青素含量的反演提供研究基础，同时也将为环境科学、生物科学等其他研究领域提供一种新的信息获取手段。