Ecological Systems: A Sourcebook of Concepts and Hypotheses.

Abstract

Too often, prospective research students have approached us needing to do research but unable to identify any coherent issue that they would like to address. Most of these students do not have any idea of the key debates in their prospective fields of specialization and know nothing about the methods and technologies that could be used in research. It is in response to this that we have written this book. The book is intended to provide essential background for prospective research students (both undergraduate and graduate) interested in working in the fields of ecosystem and community ecology. The book is really an overview and therefore intended to serve as a starting point for further exploration of the subject. Ecosystems comprise of two major components: the biotic (or living) and abiotic (non-living) components. The abiotic component of the ecosystem is essentially the conditions that exist in the ecosystem. These include the physical and chemical nature of the system and conditions such as temperature, water and nutrient availability within the system. These conditions influence and are in turn influenced by the way of life of the organisms (the biotic component) of that ecosystem. Traditionally, the study of ecosystems (ecosystem ecology) usually focusses on Nutrient Cycling and Energy Transfer. However, these two phenomena hinge on the biotic interactions that take place within the ecosystem and how these are influenced by the conditions within the system. The study of biotic relationships is known as community ecology and is usually treated distinctly from ecosystem ecology. Nevertheless, although this book is titled ‘Ecosystems’ we have included concepts in community ecology because we believe that these are essential for the understanding of ecosystems. We start the book (Chapter 1) by reminding the reader that the study of ecosystems is a branch of Ecology and that the study of Ecology is crucial to the search for solutions to increasing environmental challenges faced by our planet today. The chapter concludes with a review of the concept of an ecosystem; including a brief history of how this thinking started in the field of Ecology. Chapter 2 introduces the fundamental concepts and principles necessary for postulating hypotheses and interpreting ecological phenomena. In Chapter three, we examine ecosystem state factors. These are the factors that combine to influence the state of an ecosystem through their effects on ecosystem control factors. In Chapter 4 we review the biotic mechanisms that drive ecosystems. Chapter 5 examines the primary ecosystem processes while Chapter 6 examines the major controls that determine how these processes proceed. The book ends with Chapter 7 which introduces the concept of ecological engineering and the rise of the engineering perspective in ecosystem ecology.