基于植物水力性状的日光诱导叶绿素荧光发射机制及模拟研究

日光诱导叶绿素荧光（SIF）可用以反映植物光合能力对环境胁迫的响应，在干旱地区监测植物生理状态方面有广阔的应用前景，属于目前环境遥感领域的前沿研究。目前，在水分胁迫条件下由植物水力性状改变引起的SIF发射机制及其与总初级生产力（GPP）关联机制的变化尚未明确。因此，本项目利用对叶片-冠层尺度SIF及相关参数、光合速率以及植物水力性状的同步观测，探究作物在不同生长阶段和不同程度水分胁迫下，叶片-冠层尺度SIF发射机制和SIF-GPP关联机制的差异，从而改进STEMMUS-SCOPE模型的植物水力模块。本研究将明确SIF发射机制对水分胁迫的响应，揭示水分胁迫条件下旱区作物SIF与GPP的关联机制，从而建立基于植物水力性状的SIF前向模型，提高模型对水分胁迫的响应精度。预期结果将深化旱区SIF和植物生理生态特征耦合机制的认识，为干旱监测和预报以及农业水资源管理提供理论依据和技术支撑。

Solar-Induced chlorophyll Fluorescence (SIF) can be used to reflect the response of plant photosynthetic capacity to environmental stress. It has a broad application prospect in monitoring plant physiological status in arid areas, and it is the frontier research in the field of environmental remote sensing. To date, the emission mechanism of SIF and its relationship with gross primary productivity (GPP) caused by the change of plant hydraulic traits are not clear. Therefore, this project uses synchronous observation of leaf-canopy scale SIF and its related parameters, photosynthetic rate, and plant hydraulic characteristics to explore the differences of SIF emission mechanism between leaf and canopy scale and SIF-GPP correlation mechanism under different growth stages and different degrees of water stress, thereby to improve the plant hydraulic module of STEMMUS-SCOPE model. This study will clarify the response of the SIF emission mechanism to water stress, reveal the correlation mechanism between SIF and GPP under water stress, and establish a forward SIF simulator based on plant hydraulic traits and improve the accuracy of SIF simulation. The expected results will deepen the understanding of the coupling mechanism between SIF and plant physiological and ecological characteristics, and provide theoretical basis and technical support for drought monitoring and forecasting as well as agricultural water resources management.