宏观植物生态模型的研究现状与展望

REVIEW ON THE CURRENT STATE AND FUTURE DEVELOPMENT OF THE MACRO-SCALE PLANT ECOLOGICAL MODELS

概述了 3种主要植物生态模型的发展现状 :1 )种群动态模型 ,主要模拟在一个生态系统中单个种的植物个体发芽、成长和死亡过程 ,及其种内竞争和种间相互作用 ,是研究开发最早的一类生态模型之一。该类模型主要应用于分析植物种群之间相互作用。 2 )演替模型 ,主要模拟植物种类 (动物与此相伴 )在整个生态系统发展过程的变化 ,包括植被类型的转变和相关的生物地球化学循环过程的改变。可用于研究生物群落对气候变化的响应。 3)生态系统模型 ,是把生态系统当作一个功能整体来模拟的一类模型 ,主要有以下 3类 :(1 )SVAT模型 ,主要模拟地表生态系统过程 ,以BATS、SiB、SiB2和LEAF为代表 ,多用于气候研究 ;(2 )BGC模型 ,主要模拟 3个关键循环 :碳 ,水和营养物质循环。常用的BGC模型有 :FOREST BGC、BIOME BGC、CENTURY、TEM、DOLY以及由它们衍生而来的整合模型组 ;(3)BG模型 ,模拟群落、生物群区中植物分布 ,比较具有代表性的BGMs包括BIOME2和MAPSS ,它们主要用于研究因气候变化而引起的生物分布的变迁。最后 ,结合我们的实际工作展望了生态模型在未来几年内的几个发展方向 :1 )与基础学科相结合 ,比如把物候学引入生态模型研究中来 ,以寻求新的支撑点 ;2 )与现代非线性理论相结合 ,重新评价模型的假设基础 ;

The term of ecological model refers to a wide variety of types of models which simulate various ecosystem phenomena at different scales. Those models could be classified into various types according to different criterion. The progresses of three main macro_scale models were summarized in this paper. 1) Population dynamics models (PDMs) simulate the germination, growth and mortality of individual plants in an ecosystem, and also consider competition within species, and interaction between species. PDMs are pioneering in ecological modeling, which include individual_based models, micro_site_based competition models, matrix population models and spatially explicit population models. Those models focus on interactions between populations in an ecosystem, and ignore or maybe simplify the processes of soil_moisture_atmosphere transfer in the vertical connections. This type of model is mostly used to study the dynamic of populations. 2) Succession models (SMs) simulate the replacement of plant species (accompanying with animals) through the succession of ecosystems, including the transformation of vegetation types and the corresponding changes (influences) in biogeochemical cycling. The theoretical basis of SMs is population dynamics theory proposed by Clements, importance theory of species features in dynamic ecosystems by Gleason, ecosystem theory by Tansley, and relation theory between spatial pattern and internal dynamics within system by Watt. The models could be applied to the community responses to global climate changes. 3) Ecosystem models which take ecosystem as a functional body, include: a) Soil_vegetation_atmosphere transfer models (SVAT) that simulate land surface ecological processes, especially climatic studies. Those are BATS (biosphere_atmosphere transfer scheme), SiB (simple biosphere model), SiB2 and LEAF (land ecosystem atmosphere feedback model). SVATs simulate moisture_thermal processes of soil_plant_atmosphere continuum, based on the Monteith_Perman equation and the Darcy equation, and considering the effects of plant leaves on the selective absorption and reflection of radiations, the effects of canopies on transpiration, moisture_thermal translation and momentum exchange; b) Biogeochemistry models (BGC models) simulate the processes of photosynthesis, transpiration and decomposition and calculate the flux of the cycling of water, carbon, and nutrients on the interface of soil_vegetation_atmosphere in the ecosystems. The climate, soil condition, and vegetation types must be input as initialized variable. BGC models include FOREST_BGC, BIOME_BGC, CENTURY, TEM, DOLY and the integrated model group derived from them; 3) Biogeographic models (BGMs), which simulate the composition and distribution of vegetation on the bases of the eco_physiological adaptive of plants to the environment and the competitive capacity for resources. By using the concept of functional type, plants can be grouped into trees, shrubs and grasses or two photosynthesis types of C 3 and C 4. BGMs could be used to study organism distribution shift induced by climate change. The trends of the macro_scale plant ecological models are: firstly, linking ecological models with other sciences, for example, introducing phenology into modeling, to seek its new development; secondly, linking models with modern non_linear theories for the reevaluation of the basic hypothesis for modeling; thirdly, linking models with modern science_technology such as 3S, IT and so on, for the stronger support from technologies; and finally, the concept of model development having been altering from individulism to holistism, which simulate a ecosystem as a whole functional unit.