The chapter "A Hierarchical Concept of Ecosystems" by R. V. O'Neill, D. L. DeAngelis, J. B. Waide, and T.F.H. Allen, published by Princeton University Press, explores the hierarchical structure of ecosystems. The book is divided into four parts: 1. **The Concept of an Ecosystem**: Discusses the fundamental ambiguities in the ecosystem concept and provides a historical perspective on how ecologists have viewed ecosystems. 2. **Preliminary Considerations**: Introduces the ecosystem as a system and the concept of hierarchy, including its typical applications. 3. **A Proposal for a Theory**: Outlines elements of hierarchy theory and explains how hierarchical structure arises from evolution in open, dissipative systems. 4. **Applications of the Theory to Ecological Systems**: Explores the application of the hierarchical theory to various aspects of ecological systems, including species hierarchies, process hierarchies, and dual hierarchies. The chapter aims to provide a comprehensive framework for understanding the hierarchical organization of ecosystems and its implications for ecological research and management.The chapter "A Hierarchical Concept of Ecosystems" by R. V. O'Neill, D. L. DeAngelis, J. B. Waide, and T.F.H. Allen, published by Princeton University Press, explores the hierarchical structure of ecosystems. The book is divided into four parts: 1. **The Concept of an Ecosystem**: Discusses the fundamental ambiguities in the ecosystem concept and provides a historical perspective on how ecologists have viewed ecosystems. 2. **Preliminary Considerations**: Introduces the ecosystem as a system and the concept of hierarchy, including its typical applications. 3. **A Proposal for a Theory**: Outlines elements of hierarchy theory and explains how hierarchical structure arises from evolution in open, dissipative systems. 4. **Applications of the Theory to Ecological Systems**: Explores the application of the hierarchical theory to various aspects of ecological systems, including species hierarchies, process hierarchies, and dual hierarchies. The chapter aims to provide a comprehensive framework for understanding the hierarchical organization of ecosystems and its implications for ecological research and management.