基于夏玉米全生育期内冠层结构及生理特征变化的水碳耦合模型

Maize is one of the main food crops in China, and accurately measured and simulated crop water, carbon cycle and the coupling process is to improve the crop water use efficiency and optimize the structure of water for agriculture，so as to realize the premise of crop high efficient use of water. The project mainly includes the following three aspects: 1.Analysis of the characteristics of maize canopy structure (leaf area index, leaf angle distribution, leaf density etc.) and physiological characteristics (maximum net photosynthetic rate, photosynthetic rate maximum hydroxylation etc.) variation in the whole growth period, which lays the foundation for the establishment of the precise maize canopy water carbon coupling model. 2.Based on the field measured data of maize transpiration, to study the quantitative relationship between the diurnal variation, seasonal variation and transpiration and radiation, wind speed, air temperature and humidity environment factors, and analyze the variation of transpiration under certain weather conditions, provide data to support the water carbon coupling boundary condition of the model validation, and then provide the reference for the farmland irrigation management. 3.Through the photosynthetic model (Farquhar improved model), transpiration model (P-M model) and stomatal conductance model (Ball-berry model) coupling, considering the different characteristics of the canopy structure and physiological changes in different growth period, through the canopy structure analysis model into carbon and water coupling model to improve the model estimation accuracy.

玉米是我国主要的粮食作物之一，准确地测定和模拟作物的水、碳循环及耦合过程是提高作物水分利用效率、优化农业用水结构，从而实现作物高效用水的前提。本项目主要包括以下三个方面：1.分析玉米冠层结构特征（叶面积指数、叶倾角分布、叶片密度等）及生理特征（最大羟化速率、最大净光合速率等）在全生育期的变化规律，为建立精确的玉米冠层水碳耦合模型奠定基础。2.在农田玉米实测蒸腾数据的基础上，研究其日变化、季节变化规律以及蒸腾与辐射、风速、大气温湿度等环境因素间的数量关系，并分析特定天气条件下蒸腾的变化规律，为水碳耦合模型的边界条件验证提供数据支持，为农田灌溉管理提供参考。3.通过对光合模型（Farquhar模型等）、蒸腾模型（P-M模型等）和气孔导度模型（Ball-berry模型等）的耦合，考虑不同生育期冠层结构和生理特征变化情况，通过将冠层结构分析模型带入水碳耦合模型，以提升模型估算精度。

玉米是我国主要的粮食作物之一，准确地测定和模拟作物的水、碳循环及耦合过程是提高作物水分利用效率、优化农业用水结构，从而实现作物高效用水的前提。本项目主要包括以下三个方面：1.分析玉米冠层结构特征及生理特征（最大羟化速率、最大净光合速率等）在全生育期的变化规律，为建立精确的玉米冠层水碳耦合模型奠定基础。2.在农田玉米实测蒸腾数据的基础上，研究其日变化、季节变化规律以及蒸腾与辐射、风速、大气温湿度等环境因素间的数量关系，并分析特定天气条件下蒸腾的变化规律，为水碳耦合模型的边界条件验证提供数据支持，为农田灌溉管理提供参考。3.通过对光合模型（叶子飘模型）、辐射传输模型和气孔导度模型（叶子飘模型）的耦合，考虑不同生育期冠层结构和生理特征变化情况，进而提升模型估算精度。