Ecosystem allometry: the scaling of nutrient stocks and primary productivity across plant communities
Ecosystem allometry: the scaling of nutrient stocks and primary productivity across plant communities
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DOI：
10.1111/j.1461-0248.2006.00888.x
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发表时间：
2006-04-01
期刊：
影响因子：
8.8
通讯作者：
Enquist, BJ
中科院分区：
文献类型：
--
作者：
Kerkhoff, AJ;Enquist, BJ
生态学的一个主要挑战是整合一组个体（例如不同物种的植物）的生理功能（例如光合作用），以了解整个整体的功能（例如初级生产力）。生物体大小对生理和生态功能的控制表明，异速生长可能是跨组织层次扩展生态过程的有力工具。在这里，我们使用单个植物异速生长来预测整个植物群落中养分含量和生产力如何随植物总生物量（植物质量）变化。正如我们的模型预测的那样，从热带森林到北极苔原，净初级生产力以及整个群落的氮和磷含量都与不同植物群落的植物质量呈异速变化。重要的是，生产力数据在数量上偏离了理论上的预测，并且陆地植物群落的养分生产力（每单位养分的产量）随着植物总质量的增加而系统性地降低。这些结果与明显的竞争规模等级的存在相一致。以前未记录的这些“生态系统异速异构体”的普遍性及其在单个植物的结构和功能中的基础可能会为将植物性状与生态系统过程联系起来的研究提供有用的定量框架。
A principal challenge in ecology is to integrate physiological function (e.g. photosynthesis) across a collection of individuals (e.g. plants of different species) to understand the functioning of the entire ensemble (e.g. primary productivity). The control that organism size exerts over physiological and ecological function suggests that allometry could be a powerful tool for scaling ecological processes across levels of organization. Here we use individual plant allometries to predict how nutrient content and productivity scale with total plant biomass (phytomass) in whole plant communities. As predicted by our model, net primary productivity as well as whole community nitrogen and phosphorus content all scale allometrically with phytomass across diverse plant communities, from tropical forest to arctic tundra. Importantly, productivity data deviate quantitatively from the theoretically derived prediction, and nutrient productivity (production per unit nutrient) of terrestrial plant communities decreases systematically with increasing total phytomass. These results are consistent with the existence of pronounced competitive size hierarchies. The previously undocumented generality of these 'ecosystem allometries' and their basis in the structure and function of individual plants will likely provide a useful quantitative framework for research linking plant traits to ecosystem processes.