A New Ecology

Systems Perspective

Sven Erik Jørgensen, Brian D. Fath, Simone Bastianoni, Joao C. Marques, Felix Muller, S. Nors Nielsen, Bernard D. Patten, Enzo Tiezzi, Robert E. Ulanowicz

• Éditeur: Elsevier Science
• Année: 2011
• ISBN:
  9780080497396
• Sujet: Scienze fisiche
• Sous-sujet: Oceanografia

A New Ecology presents an ecosystem theory based on the following ecosystem properties: physical openness, ontic openness, directionality, connectivity, a complex dynamic for growth and development, and a complex dynamic response to disturbances. Each of these properties is developed in detail to show that these basic and characteristic properties can be applied to explain a wide spectrum of ecological obsevations and convections. It is also shown that the properties have application for environmental management and for assessment of ecosystem health.* Demonstrates an ecosystem theory that can be applied to explain ecological observations and rules* Presents an ecosystem theory based upon a systems approach* Discusses an ecosystem theory that is based on a few basic properties that are characteristic for ecosystmes

1

Introduction: A new ecology is needed

Publisher Summary

The political agenda imposed on ecologists and environmental managers has changed, since the focus is shifted on sustainability, which inevitably has made ecosystem functioning a core issue. 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 technologies and financial resources that they command. Ecosystem services are the benefits that 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. Currently, environmental managers have realized that maintenance of ecosystem structure and functioning 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.

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 sustainability, 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 economically 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 technologies 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.

(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 integration of, conservation and use of biological diversity.

(11) The ecosystem approach should consider all forms of relevant information, including 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. ecosystems 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 benefits 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 sufficient 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 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 management:

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 “propositions” 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 prerequisite 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 thermodynamic 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 complexity 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 pattern 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 properties. 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.

(5) Ecosystems are ...