In metabolic scaling theory the size-dependence of plant processes is described by a power function of form Y=Y o M θ where Y is a characteristic such as plant productivity that changes with plant size (M) raised to the θ th power and Y o is a normalization constant that adjusts the general relationship across environments and species. In essence, the theory considers that the value of θ arises in the size-dependent relationship between leaf area and vascular architecture that influences plant function and that Y o modulates this general relationship to account for ecological and evolutionary effects on the exchange of resources between plant and environment. Enquist and colleagues have shown from first principles that Y o is a function of carbon use efficiency, the carbon fraction of a plant, the area-specific carbon assimilation rate of a leaf, the laminar area of a leaf, and the mass of a leaf. We show that leaf longevity provides a functional integration of these traits that can serve as a simpler normalization in scaling plant productivity for individual species and potentially for mixed-species communities as well.
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机译:在代谢定标理论中,植物过程的大小依赖性通过以下形式的幂函数来描述:Y = Y o M θ sup>形式,其中Y是诸如植物生产力随植物大小(M)升高而变化的特征。到θ th sup>次方,Y o是归一化常数,可调整环境和物种之间的一般关系。从本质上讲,该理论认为θ的值出现在叶面积与影响植物功能的维管结构之间的大小相关关系中,Y o调节了这种一般关系,以说明对植物之间资源交换的生态和进化影响和环境。 Enquist及其同事从第一个原理开始表明,Y o是碳利用效率,植物的碳分数,叶片的区域特定碳同化率,叶片的层流面积和叶片质量的函数。 。我们表明,叶片长寿提供了这些性状的功能整合,可以作为一种简单的归一化方法来扩展单个物种以及潜在的混合物种群落的植物生产力。
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