A Steady-state Model of Ecological Hierarchy
Author | : Grant Garrison Thompson |
Publisher | : |
Total Pages | : 293 |
Release | : 1984 |
ISBN-10 | : OCLC:11413454 |
ISBN-13 | : |
Rating | : 4/5 (54 Downloads) |
Download or read book A Steady-state Model of Ecological Hierarchy written by Grant Garrison Thompson and published by . This book was released on 1984 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: A generalized mathematical model of ecosystems is developed. The model begins with the general class of systems known as state-determined systems, in which the time-derivative of each state variable is a function of some subset of the set of all system state variables and .environmental parameters. A formal basis is presented for considering the steady-state behavior of such systems in terms of isoclines, drawing upon the fields of graph theory, linear algebra, and differential equations. The simplifying capabilities of hierarchy theory are invoked to mitigate the adverse effects of model complexity. Like the theory of isocline analysis, the particular formulation of hierarchy theory presented is phrased in graph-theoretic terms, enabling the model to be developed as a technique for analyzing the steady-state behavior of hierarchical systems. The role of inter-level time scale heterogeneity in hierarchical organization is discussed. As an illustration of its ability to portray the behavior of spatially-nested hierarchies, the model is used to provide a perspective on data from the climax vegetation of the Great Smoky Mountains. The effects of time scale heterogeneity are also illustrated by using the model to organize data sets from several vegetation/avian communities across the United States. The vegetation is taken to behave with a lower characteristic frequency than the relatively rapidly-developing avian subcommunity, thus constraining the latter in a hierarchical fashion. In order to understand in a more general way the role such a model might play in advancing ecological understanding, a broad framework is presented for analyzing the role of conceptual structures in science and the place of models in these structures. A view of models as scientific metaphors is advanced as an alternative to the pictorial/realist interpretation of models. Given this understanding of models in general, the proposed model and its underlying assumptions are compared and contrasted with a set of four partial conceptual structures drawn from the fields of systems ecology, plant ecology, natural resource economics, and organismic systems theory.