【作者】 王靖；

【导师】 李湘阁； 于强；

【作者基本信息】 南京气象学院 ， 气象学， 2003， 硕士

【摘要】 准确地估算农田生态系统的光合和蒸散量是陆地碳循环和水循环的核心问题之一。当前国内许多农田生态系统模型对光合和蒸散分别进行模拟，机理性弱，代表性差；少数的光合与蒸散耦合模型又没有详尽考虑农田CO₂通量和水汽通量传输所涉及的各个过程，使模拟的精度不高。 本文旨在建立机理性强且模拟精度高的农田生态系统冠层光合与蒸散耦合模型。（1）建立了一个农田生态系统冠层光合和蒸散耦合模型。模型由三大模块组成；冠 层蒸散模型、冠层光合模型和土壤水热传输模型。各模块所使用的子模型都是 目前国内外机理性很强而又不过于复杂的模型。这一方面使模型有很强的机理 性可以应用到不同的地区，同时又避免模型过于复杂以保证模型模拟的准确性。 将各子模型进行系统、有机的整合建立了新的模型。（2）用涡度相关仪器所观测的数据对模型进行了验证。模型的时间步长为10min，模 型的主要输出结果有冠层CO₂通量、感热通量、潜热通量和净辐射。将模型的 模拟值和观测值进行了对比，结果显示模型的模拟值和观测值有较好的相关性， 其趋势相当一致，模拟值与观测值之间的误差小于10％。（3）对模型的主要参数进行了敏感性分析。白天冠层CO₂通量最敏感的参数是 内禀量子效率，其次，光合曲线凸度、CO₂补偿点、凋萎水势和叶面积指数的 敏感性也较强。夜间冠层CO₂通量敏感的参数是最适温度下Rubisco催化能力 和暗呼吸参数。作物蒸腾比较敏感的参数有凋萎水势、气孔导度参数、叶对红 外辐射反射率和光合曲线凸度。对于土壤蒸发，只有土壤阻力参数的敏感性较 强。（4）分析了模型对环境因子的响应。更多还原

【Abstract】 It is one of the centricity problems of carbon cycle and water cycle on terra to estimate agroecbsystem photosynthesis and evapotranspiration accurately. At present, there are many agroecosystem models in home, with insufficient mechanism and representation, simulating photosynthesis and evapotranspiration separately, and a few photosynthesis and evapotranspiration coupled models with insufficient accuracy for not considered the processes relating to the carbon dioxide and water vapor flux transfer in field detailed.So it is the purpose of this thesis to establish an agroecosystem canopy photosynthesis and evapotranspiration model with strong mechanism and high accuracy.(1) In the thesis, a canopy photosynthesis and evapotranspiration coupled model in the agroecosystem has been developed. The model consists of three modules, a canopy evapotranspiration model, a canopy photosynthesis model and a water and heat transfer in the soil model. The sub-models in every module with strong mechanism are not too complicated. Thus, the model can be applied into different areas and the accuracy of the model is high. We integrate the sub-models systematically and organically to develop a new model.(2) Validating the model with some data measured by eddy covariance method. The time step of the model is ten minutes. The main output results of the model are CO2 flux, sensible heat flux, latent heat flux and net radiation. The analysis between simulated value and observed value indicates that there is a marked correlation between them and their shapes are very accordant with error less than 10%.(3) We analyze the sensitivity of main parameters of the model. In daytime, the most sensitive parameter of the COa flux in canopy is the intrinsic quantum efficiency. The sensitivity of the convexity of photosynthesis-light response curve, COa compensation point, the wilt water potential and leaf area index are also strong. In the nighttime, the sensitive parameters of the CO2 flux in canopy are the Rubisco catalytic capacity of at optimal temperature and the dark respiration parameter. The sensitive parameters of canopy transpiration are the wilt water potential, the stomata conductance parameter, the albedo of leaves to the infrared radiation, and the convexity of photosynthesis-light response curve. The sensitive parameter of soil evaporation is only soil resistance parameter.(4) Analyzed the respons of the model to environmental factors.更多还原