1 Introduction: A new ecology is needed 1.1 ENVIRONMENTAL MANAGEMENT HAS CHANGED The political agenda imposed on ecologists and environmental managers has changed since the early 1990s. Since the Rio Declaration and Agenda 21 the focus has been on sus- tainability, which inevitably has made ecosystem functioning a core issue. Sustainability Development is, according to the Rio Declaration, defined as follows: “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” And, the contrasting parties are invited to, “act in a way that is eco- nomically profitable, socially acceptable, and environmentally compatible.” Already the Rio Declaration emphasized the importance of ecosystems in Principle 7: States shall cooperate in a spirit of global partnership to conserve, protect, and restore the health and integrity of the Earth’s ecosystems. In view of the different contributions to global environmental degradation, states have common but differentiated responsibilities. The developed countries acknowledge the responsibility that they bear in the international pursuit of sustainable development in view of the pressures their societies place on the global environment and of the tech- nologies and financial resources they command. The Convention of Biodiversity adopted, in 2000, 12 principles—called the Ecosystem Approach—that placed the ecosystem concept even more centrally into environmental management considerations. It is particularly clear from the last 10 of the 12 principles: (1) The objectives of management of land, water, and living resources are a matter of societal choice. (2) Management should be decentralized to the lowest appropriate level. (3) Ecosystem managers should consider the effects (actual or potential) of their activities on adjacent and other ecosystems. (4) Recognizing potential gains from management, there is usually a need to understand and manage the ecosystem in an economic context. Any such ecosystem-management program should: a. Reduce those market distortions that adversely affect biological diversity. b. Align incentives to promote biodiversity conservation and sustainable use. c. Internalize costs and benefits in the given ecosystem to the extent feasible. 1 Else_SP-Jorgensen_ch001.qxd 3/31/2007 08:36 Page 1 2 A New Ecology: Systems Perspective (5) Conservation of ecosystem structure and functioning, in order to maintain ecosystem services, should be a priority target of the ecosystem approach. (6) Ecosystems must be managed within the limits of their functioning. (7) The ecosystem approach should be undertaken at the appropriate spatial and temporal scales. (8) Recognizing the varying temporal scales and lag-effects that characterize ecosystem processes, objectives for ecosystem management should be set for the long term. (9) Management must recognize that change is inevitable. (10) The ecosystem approach should seek the appropriate balance between, and integra- tion of, conservation and use of biological diversity. (11) The ecosystem approach should consider all forms of relevant information, includ- ing scientific and indigenous and local knowledge, innovations, and practices. (12) The ecosystem approach should involve all relevant sectors of society and scientific disciplines. Also in the book Ecosystems and Human Well-being, a Report of the Conceptual Framework Working Group of the Millennium Ecosystem Assessment from 2003, ecosys- tems are the core topic. In Chapter 2 of the book, it is emphasized that: an assessment of the condition of ecosystems, the provision of services, and their relation to human well- being requires an integrated approach. This enables a decision process to determine which service or set of services is valued most highly and how to develop approaches to maintain services by managing the system sustainably. Ecosystem services are the bene- fits people obtain from ecosystems. These include provisioning services such a food and water; regulating services such as flood and disease control; cultural services such as spiritual, recreational, and cultural benefits; and supporting services such as nutrient cycling, which maintain the conditions for life on Earth. Today, environmental managers have realized that maintenance of ecosystem structure and functioning (see Principle 5 above) by an integrated approach is a prerequisite for a successful environmental management strategy, which is able to optimize the ecosystem services for the benefit of mankind and nature. Another question is whether we have suf- ficient knowledge in ecology and systems ecology today to give the needed information about ecosystem structure, function, and response to disturbance to scientifically pursue the presented environmental management strategy and ecosystem sustainability. In any way, the political demands provide a daunting challenge for ecosystem ecology. 1.2 ECOLOGY IS CHANGING As a consequence of the changing paradigm direction of environmental management, we need to focus on ecosystem ecology. An ecosystem is according to the Millennium Report (2003) defined as “a dynamic complex of plants, animals and microorganism communities and the nonliving environment, interacting as a functional unit. Humans are an integral part of ecosystems.” A well-defined ecosystem has strong interactions among its components and weak interactions across its boundaries. A useful ecosystem boundary is the place where a Else_SP-Jorgensen_ch001.qxd 3/31/2007 08:36 Page 2 number of discontinuities coincide for instance in the distribution of organism, soil type, drainage basin or depth in a water body. At a larger scale, regional and even globally distributed ecosystems can be evaluated based on a commonality of basic structural units. Three questions are fundamental to pursue for ecosystem-based environmental man- agement: I: What are the underlying ecosystem properties that can explain their response to perturbations and human interventions? II: Are we able to formulate at least building blocks of an ecosystem theory in the form of useful propositions about processes and properties? We prefer the word “proposi- tions” and not laws because ecosystem dynamics are so complex that universal laws give way to contextual propensities. The propositions capture these general tendencies of ecosystem properties and processes that can be applied to understand the very nature of ecosystems, including their response to human impacts. III: Is the ecosystem theory that we can formulate to understand ecosystem properties sufficiently developed to be able to explain ecological observations with practical application for environmental management? The scope of the book is an attempt to answer these questions to the extent that is currently possible. The authors of this book have realized that an ecosystem theory is a pre- requisite for wider application of ecological sciences in environmental management because theory provides a strong guide for environmental management and resource conservation. 1.3 BOOK OUTLINE Chapters 2–7 present the fundamental properties that explain typical ecosystem processes under “normal” growth and development and their responses to disturbance. These are: (1) Ecosystems are open systems—open to energy, mass, and information. Openness is an absolute necessity because the maintenance of ecosystems far from thermody- namic equilibrium requires an input of energy. This core property is presented in Chapter 2. (2) Ecosystems are ontically inaccessible—meaning that due to their enormous complex- ity it is impossible to accurately predict in all detail ecosystem behavior. It means that it is more appropriate to discuss the propensity of ecosystems to show a certain pat- tern or to discuss the direction of responses. This property is presented in Chapter 3. (3) Ecosystems have directed development—meaning they change progressively to increase, in particular, feedback and autocatalysis. It is the observed direction of responses mentioned under point 2. This property is discussed in detail in Chapter 4. (4) Ecosystems have network connectivity—which gives them new and emergent prop- erties. The networks have synergistic properties, which are able to explain the cooperative integration of ecosystem components, which can at least sometimes yield unexpected system relations. This core property is covered in Chapter 5. Chapter 1: Introduction 3 Else_SP-Jorgensen_ch001.qxd 3/31/2007 08:36 Page 3 (5) Ecosystems are organized hierarchically—in the sense that we can understand one level only by understanding interactions with the levels below and above the scale of focus. Often major changes in one level are leveled out in the higher levels, where only minor hierarchical organization changes are observed. The properties associated with the are discussed in great detail by Allen and Starr (1982) in their book Hierarchy, Perspectives for Ecological Complexity and in the book A Hierarchical Concept of Ecosystems by O’Neill et al. (1986). The scaling theory and the allomet- ric principles are rooted in quantification of openness and are, therefore, presented in Chapter 2. The basic general elements of hierarchy theory are also presented in this chapter. Further examples of the application of hierarchy theory are presented in Chapters 3 and 7. (6) Ecosystems grow and develop—they gain biomass and structure, enlarge their networks, and increase their information content. We can follow this growth and development using holistic metrics such as power, eco-exergy, and ascendency, respectively. For example, incoming solar radiation is first used to cover maintenance of the ecosystem far from thermodynamic equilibrium and afterwards used to move the system further from equilibrium, which increases the power, stored eco-exergy, and ascendency. This growth property is presented in Chapter 6. It is a core property because it explains how ecosystems develop and even evolve. Many ecosystem processes are rooted in the competition for the resources that are needed for growth and can be explained in this light. (7) Ecosystems have complex response to disturbance—but when we understand prop- erties of ecosystems such as adaptation, biodiversity, resistance, and connectedness, to mention a few of the most important properties covered in the book, we can explain and sometimes predict the responses of ecosystems to disturbances. This part of the ecosystem dynamics is presented in Chapter 7. Chapters 2–7 are directed to answer first question above. The second question is answered throughout these chapters and summarized in Chapter 10, where the presented ecosystem theory is formulated by use of the seven properties and by formulation of ten propositions. The two formulations are completely consistent as discussed in this last chapter of the book. The last question regarding the applicability of the presented theory to explain eco- logical observations and to be applied in environmental management is addressed in Chapters 8 and 9. The application of the theory in environmental management has been mostly limited to use of ecological indicators for ecosystem health assessment as described in Chapter 9. The theory has much wider applicability, but the use of ecological indicators has a direct link to ecosystem theory that facilitates testing the theory. Tests of the theory according to its applicability in practical environmental management and to explain ecological observations is crucial for the general acceptance of the ecosystem theory of course; but it does not exclude that it cannot be improved significantly. On the contrary, it is expected that the theory will be considerably improved by persistent and ongoing application because the weaknesses in the present theory will inevitably be uncovered as the number of case studies increases. Discovery of theoretical weaknesses 4 A New Ecology: Systems Perspective Else_SP-Jorgensen_ch001.qxd 3/31/2007 08:36 Page 4 will inspire improvements. Therefore, it is less important that the theory has flaws and lacks important elements than it is that it is sufficiently developed to be directly applied. We, the authors, are of the opinion that we do have an ecosystem theory today that is ready to be applied but which also inevitably will be developed significantly during the next one to two decades due to (hopefully) its wider application. An ecosystem theory as the one presented in this book may be compared with geo- graphical maps. We had already 2000 years ago geographical maps that could be applied to get an overview of where you would find towns, mountains, forests, etc. These maps were considerably improved and the geographical maps used in the 17th and 18th century were much more accurate and detailed, although they are of course not comparable with the satellite-based maps of today. Our ecosystem theory as presented today may be com- parable with the geographical maps of the 18th century. They are, as the more than 200 years old geographical maps, very useful, but they can be improved considerably when new methods, additional information, and additional observations are available. It may take 20 or maybe 50 years before we have the quality of an ecosystem theory comparable with today’s geographical maps, but the present level of our ecosystem theory is never- theless suitable for immediate application. Only through this application we will discover new methods and demand for improvements, both theoretical and practical for science and management, ultimately leading to a more complete and accurate ecosystem theory. The most fundamental parts of the presented ecosystem theory, particularly the more mathematical aspects, are placed in boxes. It makes it on one hand easy to find the theo- retical elements of the entire ecosystem theory but it also facilitates reading for those preferring a less mathematical formulation of an ecosystem theory. Chapter 1: Introduction 5 Else_SP-Jorgensen_ch001.qxd 3/31/2007 08:36 Page 5 This page intentionally left blank . 1 Introduction: A new ecology is needed 1. 1 ENVIRONMENTAL MANAGEMENT HAS CHANGED The political agenda imposed on ecologists and environmental managers has changed since the early 19 90s organism, soil type, drainage basin or depth in a water body. At a larger scale, regional and even globally distributed ecosystems can be evaluated based on a commonality of basic structural. considerably when new methods, additional information, and additional observations are available. It may take 20 or maybe 50 years before we have the quality of an ecosystem theory comparable with