Macroecology: The Organizing Forces
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- 作者：Lionel Johnson
- 刊名：Biotechnology Progress
- 出版年：2006
- 出版时间：February 2006
- 年：2006
- 卷：22
- 期：1
- 页码：156 - 166
- 全文大小：540K
- 年卷期：v.22,no.1(February 2006)
- ISSN：1520-6033
文摘
The fundamental problem in ecology is the relationship between organisms and the physicalworld. This question is approached through the study of ecosystems as wholes. Pristine,autonomous Arctic lakes provide an invaluable starting point for such investigations. Studieson these lakes, initiated in 1958, indicate that the dominant fish populations assume a recognizableand repeatable structure, which if not disturbed by external forces, is maintained indefinitely.The observable characteristics are high biomass, large individual size, great age, uniformity ofindividuals despite great variation in age, and relatively few juveniles. This configuration expressesa state of least specific energy dissipation or least specific entropy production and may be regardedas a standing wave in the energy flow. Similar characteristics were found in the dominant speciesin a wide range of ecosystems worldwide. A state of least dissipation develops when two energytransport processes interfere with each other in the vicinity of thermodynamic equilibrium. Thusit is postulated that living organisms originated through the agonistic interaction between twoenergy transport processes within materials, initially occurring in an environment close tothermodynamic equilibrium. These two processes, fundamental to energy transfer, are recognizedas the principle of least action and its diametrical opposite, the principle of most action. Eachforce dominates system behavior in a different time frame: most action in the short-term(ecological time) and least action over the long-term (evolutionary time). Interaction betweenthe countervailing forces provides an understanding of a wide range of emergent ecologicalgeneralities such as succession, r- and K-selection, the stability and diversity of ecosystems,and the directionality of evolutionary change.