环境因素对SIF-GPP定量关系的影响机理与建模研究

基于日光诱导叶绿素荧光（SIF）的全球植被总初级生产力（GPP）估算是GPP遥感监测的颠覆性创新，但诸多研究表明，SIF与GPP对环境因素的响应规律差异是SIF-GPP模型的重要不确定性来源之一。项目将聚焦环境因素对SIF-GPP定量关系的影响机理与建模这一有待解决的科学问题，通过理论推导与叶片、冠层水平的实验观测研究，分析SIF与GPP随环境因素的变化规律及其内在生理机制；阐明光能利用率（LUE）和荧光量子产率（Φ_F）的关键影响因子及其响应特征；构建光能利用率与荧光量子产率比值（LUE/Φ_F）对关键环境因子响应的数学模型，从而将环境因素的影响耦合进SIF-GPP模型，提高基于SIF的GPP估算精度和普适性。项目成果将可促进SIF遥感机理与应用研究的发展，对全球碳循环遥感研究具有重要意义。

The estimation of global gross primary productivity (GPP) based on solar-induced chlorophyll fluorescence (SIF) is a disruptive innovation for GPP monitoring by remote sensing. But a number of studies have shown that the difference in the response of SIF and GPP to environmental factors is an important uncertainty for the SIF-GPP model. This project will focus on the unresolved scientific problem of the mechanism and modeling of influence on the SIF-GPP relationship by environmental factors. Firstly, we will analyze the patterns of SIF and GPP varying with environmental factors and their physiological mechanism through theoretical derivation and experimental observations at the leaf and canopy levels; then, we will clarify the key influencing factors of light use efficiency (LUE) and fluorescence quantum yield (Φ_F) and their response characteristics; and finally, we will build an optimized SIF-GPP model coupling the influence of environmental factors by modelling the relationship between LUE / Φ_F and key environmental factors, to improve the accuracy and applicability of the SIF-GPP model. The achievements of this project could promote the development of the mechanism and application of remote sensing on SIF, and is of great significance in the remote sensing research on global carbon cycle.