Progresses in Modeling Plant Ecophysiological Processes in the Study of Terrestrial Carbon Cycles
陆地碳循环研究中植物生理生态过程模拟进展

The modeling of ecophysiological processes of plants is very important in terrestrial carbon cycle models. During the last two decades, many terrestrial carbon cycle models have been developed for various purpose and scales. In this paper, the models of three ecological physiological processes in the carbon cycle models, which are directly related to the physical land surface processes are reviewed. These models include photosynthesis, carbon allocation and phenology models. Photosynthesis model Three photosynthesis model types are classified. Semi\|empirical models simulate the photosynthesis rate as a function of environmental factors and derive the maximum photosynthesis rate from experiments or semi\|empirical methods. The mechanical photosynthesis models consider the biochemical mechanism of photosynthesis. The photosynthesis rate is determined by the lower one of the photosynthesis rate determined by Rubisco and the rate controlled by the regeneration of RuBP. The third type of model uses remote sensing data, in which the net primary production is a function of the efficiency of photosynthesis and the active photosynthesis radiation. Carbon allocation model Five types of carbon allocation models are introduced. (1) The function balance model: its hypothesis is that there is a function balance between the size and activity of the branches of the plant and the size and activity of its roots. (2) The transport\|resistance model is a kind of semi\|empirical model, based on the theory of transport and utilization. It simulates the growth and allocation of forest based on the pool and fluxes of carbon and nitrogen. The carbon flux is a function of the gradient and transfer conductance of carbon. (3) The photosynthesis: growth model gives the relative growth rate of the plant as a function of the net assimilation rate, leaf weight ratio, and specific leaf weight. (4) The environmental responses model. (5) The carbon allocation model in large scales ecosystem modeling is usually simplified. The responses of vegetation growth to the environment are given as simple curves or prescribed as a constant. Phenology model A statistical phenology model based on observational data gives the phenology image of the local vegetation. Because of the complex control mechanism and very different characteristics in different regions, the phenology of vegetation has different patterns. The use of remote sensing data, such as NDVI, is a way to solve this problem. Thus the vegetation phenology is derived from the seasonal dynamics of NDVI by the phenology model based on a remote sensing data model. The problems and the prospective development of ecological processes modeling in carbon cycle models are discussed.