沙区植物生态位构建的数学模型及其应用研究

生态位构建理论是对生态位研究的新进展.以沙区植物梭梭为研究对象,从进化生态学角度探讨了沙区植物生态位构建机理,扩展了生态位构建的概念,建立了沙区植物种生态位的n维"超体积"构建模式、构建作用的动力学模型及适宜度计测公式.实例分析表明:梭梭的生态位构建作用主要表现在干旱环境的适应性特征上,它能改变和营建局部环境,其多枝的形态结构与叶面生理代谢特征,能有效地截留降水、富集养分在根部土壤中发育为肥岛.计算结果显示,在种植密度梯度上,随着营林密度的减少,其构建动力和适宜度呈上升趋势,试验条件下密度为518株*hm-2时具有最大的构建动力和最高适宜度值,这为梭梭人工林营建提供了定量依据.

Mathematical Model of Niche Construction for Desert Vegetation and Its Applications

Niche construction theory is a development of niche research. Taken the desert vegetation as the research object, this paper will, in terms of evolutionary ecology, discuss the mechanism of niche construction for desert vegetation, develop the concept of niche construction by K N Laland et al., set up the construction pattern of n-dimensional super-volume niche, upbuild the dynamical model for construction effect and measures for the calculation of niche fitness. Experimental results show that the niche construction effect of \%Haloxylon Ammodendron\% is mainly represented by the adaptive property for arid environment, which can change and construct local environment. In addition, its multi-wattle modality structure and leaf character for physiological metabolizing can effectively hold and save water, and accumulate nutrients around roots to develop fertile island. Calculated results show that construction force and fitness increase with the decrease of artificial forest density, which reach the maximum for construction force and fitness under the condition of 518 individuals per hectare. This can support quantitatively the artificial construction of \%Haloxylon Ammodendron\% forest.