滨海湿地具有较高的碳汇价值，准确评估湿地植被初级生产力是研究生态系统碳循环过程的关键环节，而结合不同植被类型的生理生态学特性与时空分布格局动态是区域性植被初级生产力研究的发展趋势。本项目以长江口湿地及典型盐沼植物-芦苇（土著C3植物）和互花米草（外来C4植物）为研究对象，根据不同潮滩类型的水位与盐度条件设置控制实验和野外观测，1）研究完整生命周期的植物光合酶促作用、自养呼吸、碳固定和生物量分配等过程，及其对不同实验处理的适应机理；2）构建基于C3和C4植物生理生态过程的生产力模型，并针对不同水/盐条件下的芦苇和互花米草进行模型参数化与验证；3）采用多源的遥感数据进行信息提取和植被季相参数反演，耦合并优化"植物生理生态过程-遥感"模型，根据"个体-群落-区域"尺度上植物生理生态过程的环境适应特征，研究互花米草引入以来（自2000年），长江口湿地典型植被初级生产力的时空格局动态及其驱动机制。

Natural coastal wetlands have been identified as the valuable carbon sinks. To accurately estimate the primary productivity of plants in wetlands is important to studying the biogeochemical cycle of carbon, and the combined consideration on eco-physiological characteristics and spatio-temporal dynamic distribution pattern of different types of vegetation is the developing trend of research on regional primary productivity of plants. This project will take Yangtze estuarine wetland and the typical saltmarsh vegetation - Phragmites communis (native C3 grass) and Spartina alterniflora (introduced C4 grass) as the research objects. .Based on the controlled experiments (according to water tables and salinity variations of different types of tidal flat) and field survey, the aims of this study are (1) to investigate the eco-physiological mechanism processes of photosynthetic enzymatic responses, autotrophic respiration, carbon fixation and biomass allocation of Phragmites communis and Spartina alterniflora, as well as the adaptive mechanism of eco-physiological processes to the treatments of water table and salinity, (2) to construct, parameterize and validate a process-based productivity model with C3 and C4 eco-physiological processes under different treatments of water and salinity, (3) based on the information extraction (construction features of wetland) and parameter retrieval of vegetation season-phase characteristics (LAI etc.) of Phragmites communis and Spartina alterniflora, to analyze the driving mechanism of spatio-temporal dynamics of primary productivity of the typical plants in Yangtze estuarine wetland, by the adaptive features of eco-physiological processes scaling from individual to community and to region, based on the integration and optimization of "process-remote sensing" model. This project looks forward to order to providing a scientific basis for the conservation strategies on capacity of carbon sink in eastern coastal wetlands of China.