Chapter 6 "Valuing Nature's
Services" in State
Costanza
et al. (1997)
Dobson
et al. (1997)
Chapter 6 "Valuing Nature's
Services" in State
Costanza
et al. (1997)
Dobson
et al. (1997)
Carpenter
and Cottingham (1997) Resilience and restoration of lakes
DeLeo
and Levin (1997). The Multifaceted Aspects of Ecosystem Integrity
Peterson
et al. (1997). Uncertainty, Climate Change, and Adaptive Management
Ludwig
et al. (1997) Sustainability, Stability, and Resilience
Sustainable
Biosphere Initiative (Ecological Society of America 1997)
"Ecology, insofar as required for practical problem solving of environmental problems, is more of a science of case studies and statistical regularities, than a science of exceptionless, general laws…it is more of a science that moves from a singular to theoretical explanation, than one that proceeds from theoretical to singular explanation. For practical problem solving, "bottom-up" approaches to ecological explanation are likely more fruitful than "top-down" although both are needed. "Top-down" approaches tend to use an account of theoretical explanation to underwrite talk about fundamental mechanisms and identification of causes in particular cases. "Bottom-up" approaches tend to focus on specific phenomena; they emphasize our ability to see causal relations in such phenomena and then to pull together results about individual cases or events into some sort of theoretical explanation" (Shrader-Frechette and McCoy 1993).
The more complex the problems with the World, the more the need for interdisciplinary approaches and tools for improved policy making, management, and directed action for change. As with the pedagogy of sustainability, defining and discussing the definition of what is an ecosystem is an important aspect for natural systems management. Ecosystem and ecosystem management concepts need not only academic and textbook-type definitions but also operational and management ones. While the term "ecosystem" is familiar to many people, standard textbook definitions are imprecise and inadequate for policy formulation and management purposes (Gonzales 1996).
Standard textbook definitions are mainly from Odum (1971, 1993) and Ricklefs (1983) who define an ecosystem as "the community and the non-living environment functioning together". In the Russian and German literature, an ecosystem is a "biogeocoenosis" (life and Earth functioning together).
Lutz (1902) defined ecology as "the science of cause". It is constantly asking "Why?" and not until can we can answer "because," have we solved a problem in ecology. It is the capping stone of the other branches of biological investigation. Morphology describes an organ or character; physiology shows us how it works and what it does; ecology, building on these, tells how and why the character or organ arose. It, then, must be considered as more than the old Natural History. Although the value of the latter cannot be overestimated, more must sooner or later be done."
The US EPA defines an ecosystem as "a dynamic complex of plant, animal, and microorganism communities and their non-living environment interacting in a functional unit" (EPA 1994).
The vague nature of the ecosystem concept is especially perplexing to managers and policy-makers who are challenged to rank threats to individual ecosystems at risk as a means of prioritizing agency's responses to threatened ecosystems (Gonzalez 1996).
The ecosystem concept has at least two main schools of thought:
Organism-centered view,
or,
Landscape-centered view.Ecosystem managers have preferred to take a "place-driven" approach to environmental protection (the landscape-centered view), while many academic ecologists have chosen the organism-centered view, but there is much debate on what are the keys to ecosystem management.
Gonzalez (1996) proposes a working definition of an ecosystem as "a volume of air, land, and water with natural boundaries, delineated primarily by landscape features and climatic factors, encompassing a set of natural ecological processes, organisms, and anthropogenic processes that function within a hierarchy of volumes". O'Neill et al. (1986) suggests that an ecosystem must "be defined relative to the scale of the problem being addressed".
There is widespread agreement among workers that it is important to know and choose the proper level within the nested hierarchy of ecosystems when conducting ecological research or monitoring environmental problems. Knowledge of the "level" of investigation is also important for the social system being investigated (world, nation, state, county, town, etc.). States Odum (1993), "the challenge is to recognize the unique characteristics of the level selected and then devise appropriate methods of study and/or action".
A hierarchy is an arrangement of a graded series of steps, from larger levels of organization to smaller levels. Odum (1993) talks about hierarchy as a series of Chinese boxes, with one box inside of a box, inside of a box, and so on. Using this analogy, the largest box would be the biosphere, followed by biomes, landscapes, ecosystems, communities, populations and organisms. The biosphere is a term used for all of the earth's ecosystems functioning together on a global scale.
The ecological notion of "hierarchy" is not at all congruent with the common notion of hierarchy that controls political or social processes from above and direction (and sometimes, abuse of power). Ecosystems display synergistic interaction of levels, which may be one major force driving evolutionary change. This is due the emergent property principle, or what is commonly known as, "the whole is greater than the sum of its parts" (=synergy). There are emergent (e.g. new) properties that arise along the scale of ecological organization, such that one could never understand the forest by studying all its trees, for example. The forest itself has unique properties.
A system has been said to be "anything that the mind puts boundaries on". In other words, a system is a "space" with boundaries. Other characteristics are that a system has input, output and recycling characteristics. Ecological systems are very complex, so we use models to help study them. A model is a simplified version of a real-world situation. Ecosystem models are built on energy and materials, where energy flows, and matter is transformed.
Energy in ecosystems is governed by the two laws of thermodynamics:
Energy may be transformed
but is never created or destroyed, and
Energy flows from a concentrated
to a dispersed form. Autotrophic (self-nourishing),
that fixes light energy and makes organic foods out of inorganic substances
such as water, carbon dioxide and nutrients, and,
Heterotrophic (other-nourishing)
component, that utilizes and decomposes complex organic matter, breaking
it down to simpler inorganic forms, such as herds of antelope (and cities).There are ecologically functional equivalents all over the globe where the environments are similar.
In addition there are keystone species that exert some sort of controlling influence over ecosystem organization whether or not they play a dominant role numerically (Mills et al. 1993).
Functional classifications of ecosystems such as these are not to be confused with taxonomic classifications although there are certainly parallels. Taxonomists assess the physical aspects and structural relationships within and between organisms and discern evolutionary pathways. While there are classic arguments between the "lumpers" and the "splitters", taxonomists play a vital role in cataloguing the Earth's vast array of life, or biodiversity. The biodiversity of the earth's biosphere is measured by the numbers of different types of species existing per unit area. There is not only an alarming loss of biodiversity or the planet, but also of taxonomists! These trends endanger our ability to understand and manage the Earth's ecosystems for sustainability.
One characteristic of natural communities is that they have few common species and many rare ones at any place and time (Odum 1993). One way of measuring this degree of dominance is by the "Simpson Index".
ECOSYSTEMS SERVICES
Ecosystem functions are the processes of ecosystems
(photosynthesis, nutrient recycling, decomposition, waste absorption, etc.).
Ecosystem goods (ex. food) and functions represent "the benefits human
populations derive, directly or indirectly, from ecosystem functions" (Costanza
et al. 1997).
Costanza et al. (1997) define capital as "the stock
of materials or information that exists at a point in time".
Costanza et al. (1997) defines ecosystem goods and services as "flows of materials, energy, and information from natural capital stocks which combine with manufactured and human capital services to produce human welfare". There are 17 ecosystem services defined in their study:
gas regulation
climate regulation
disturbance regulation
water regulation
water supply
erosion control and sediment
retention
soil formation
nutrient cycling
waste treatment
pollination
biological control
refugia
food production
raw materials
genetic resources
recreation
cultural.
Abramovitz (1997) defines 14 ecosystem services on page 96 in State of the World 1997.
Costanza et al. (1997) estimate the value ecosystem goods and services to be US$ 16-54 trillion per year. They estimate the global gross national product (GNP) of US$ 18 trillion per year. They mention that the world's GNP would be very different if it adequately incorporated ecosystem services and state that if such accounting was actually practiced it would change the planning structure of governments and how projects were appraised.
For example, a project to convert wetlands in the Pantanal area of southwestern Brazil would be shown to make no economic sense if the ecosystems services of the wetlands were taken into account and compared versus the value of the soybeans to be produced (Pimm 1997). Many other examples of this type of environmental accounting are given in Chapter 6 by Abramovitz (1997).
There has been much controversy about these ideas, principally from people who believe that some of the Earth's services are irreplaceable and therefore have infinite value. But there is also a danger that by utilizing the "language" of economists (e.g. money) to measure the Earth's ecosystem services that some economists and developers could equate ecosystems services (natural capital) to financial capital, as if they were a one-to-one trade off. Then, we could "run a deficit" which could be fixed at some future time, like financial debt (Fiscus 1997).
ECOSYSTEMS MANAGEMENT
One of the ways of operationalizing ecosystems has been the evolution of ecosystems management. Ecosystems management has been defined as "the use of an ecological approach in land management to sustain diverse, healthy, and productive ecosystems, in order to blend long-term societal and environmental values, and to do so in a dynamic manner that may be adapted as more knowledge is gained through research and experience" (Roe 1996).
Lackey (1997) defines ecosystem management in a similar manner that takes into account social concerns, "The application of ecological and social information, options, and constraints to achieve desired social benefits within a defined geographic area and over a specified period."
Grumbine (1994) extends the time period in his definition of ecosystems management, "Ecosystem management integrates scientific knowledge of ecological relationships within a complex sociopolitical and values framework towards the general goal of protecting native ecosystem integrity over the long run."
Lackey (1997a) states there are two fundamentally different world views of ecosystems: biocentric and anthropocentric. Biocentric views concern maintenance of ecological health and integrity as the primary goals, with humans and their uses secondary. Anthropocentric views consider human first, nature second. Management is by nature an anthropocentric view of ecosystems since they are based on values and priorities. The management challenge is to find out what society wants as its goal, then design a strategy or management mix of decisions to reach that goal (Lackey 1997a).
There are 5 goals of ecosystem management (Grumbine 1994):
maintain viable populations
of all native species in situ;
represent all native ecosystem
types across their natural range of variation;
maintain evolutionary and
ecological processes;
manage over long periods
of time to maintain the evolutionary potentials of species and ecosystems;
accommodate human use and
occupancy within these conditions.ecosystem management is a
stage in the continuing evolution of social values and priorities, it is
neither a beginning or an end;
ecosystem management is place-based
and the boundaries of the place must be clearly and formally defined;
ecosystem management should
maintain ecosystems in the appropriate condition to achieve desired social
benefits;
ecosystem management should
take advantage of the abilities of ecosystems to respond to a variety of
stresses, natural and man made;
ecosystem management may
or may not result in an emphasis on biodiversity;
sustainability should be
clearly defined, especially the time frame, benefits and costs of concern
and the relative priorities of benefits and costs; and
scientific information is
only one element in a decision-making process that is fundamentally one
of public and private choice.
Ecosystem management goals are also imprecise because these involve socio-political considerations, not only biology. The best ecosystem managers today have to achieve not only environmental sustainability for the ecosystem's sake, but also socially desirable ecosystem management. The dominant areas of ecosystem management investigation today are (Grumbine 1994):
use of a hierarchical
context to seek connections between all levels of the ecosystem, even
though an action may be working only at one level;
definition of ecological
boundaries;
preservation of ecological
integrity defined as managing for protection of natural diversity and
ecological patterns and processes that maintain it;
adaptive management,
or the ability to adapt to changing circumstances/new data;
promoting the concept that
humans are embedded in nature, and reforming environmental values
so that people change their view of the Earth from an outmoded one of where
the Earth is "resources", a place to be harvested or used, and transformed
into "goods and services", into the concept of the Earth as our only "home",
a place that we sustain for future generations (intergenerational sustainability),
and where people become stewards rather than exploiters.define societal expectations;
integrate societal expectations
within the sustainable capacity of ecosystems; and
fill information gaps in
the historical knowledge of the form and functions of ecosystems. Lackey (1997b) believes the limits to ecosystem management
is not the lack of knowledge about the natural science aspects of the issue
but rather policy problem and issues that "are every bit as challenging
as those in welfare and economic issues". As a result, the three major
challenges to ecosystem management according to Lackey (1997) are:
better defining the concept
of ecosystem health. "Is a wilderness area defined as the base level? Is
it the degree of perturbation by human activities".
finding better ways to use
science. As structured science is too narrow and ecosystem management too
complex for "easy or rapid scientific experimentation or analysis".
methods to evaluate public
preference and priorities. What does the public's stated need to preserve
biodiversity really mean in practice?
developing better ways to
present opinions and consequences to the public, policy analysts and decision-making.
Making information understandable to the lay public.
Ecological Engineering and Ecotechnology
There is a need to develop an ecology that restores damaged natural and social systems. Some (Straskraba 1997) have defined this as ecotechnology. Mitsch (1993) says that ecotechnology is "cases where the energy supplied by man is small relative to the natural sources, but sufficient to produce large effects in the resulting {ecosystem} patterns and processes"; and as "environmental manipulation by man using small amounts of supplementary energy to control systems in which the main energy drives are still coming from natural sources".
The goals of ecotechnology are:
Cairns (1988) describes this directly: "One of the most compelling reasons for the failure of theoretical ecologists to spend more time on restoration ecology is the exposure of serious weaknesses in many of the widely accepted theories and concepts of ecology".
Chinese ecological engineering is defined by Ma (1988) as a "specially designed system of production processes in which the principles of species symbiosis and the cycling and regeneration of substances in an ecological systems are applied...to make a multi-step us of substances."
One example is agroecological engineering. A system combining fish ponds, agroforestry, animal husbandry, herb and wood production is used, with an emphasis and multiple use of inputs and waste recycling through many pathways. The ecological principles of self-design, self-organization, and capacity of ecosystems are used. The differences between Chinese and Western styles of ecological engineering are largely the heavy human intervention and subsidies, and the total focus on food production in China (Mitsch 1993; Mitsch et al. 1993).
Chinese ecological ecosystem principles are:
1. adding new food chain components
2. promoting symbioses
3. using multi-layering of wastes as resources in food chains
4. promoting recycling
5. restoration of ecosystems.
An excellent example of using the Chinese principles in ecological engineering is the industrial ecology experiment in Fiji (Kane 1997).
Abromovitz, J. 1997. State of the World Chapter 6, "Valuing nature's services".
Beyeler, M. and E. Eger. 1997. Ecosystem management: progress or eyewash? California Coast and Ocean Winter 96-97: 30-35.
Carins, J. 1988. Rehabilitation of Damaged Ecosystems. CRC Press, Boca Raton, FL.
Costanza, R. et al. 197. The value of the world's ecosystem services
and natural capital. Nature 387: 253-260.
EPA. 1994. The new era of environmental protection: EPA's five year
strategic plan. EPA 200-B-94-002.
Engleman and LeRoy. 1996. Sustaining Water: Population and the Future of Renewable Water Supplies. Population Action International.
EPA. 1994. National water quality inventory, 1992: Report to Congress. Office of Wetlands, Oceans and Watersheds, US EPA, Washington, DC.
Fiscus, D. 1997. Re: valuation of ecosystems. E-mail to Ecolog-L listserv discussion list, 9/11/97.
Gonzalez, O. 1996. Formulating an ecosystem approach to environmental protection. Environmental Management 20: 597-605.
Grumbine, R. 1994. What is ecosystem management? Conservation Biology 8: 27-38.
Kane, H. 1997. Eco-farming in Fiji. Worldwatch 10(4): 29-34.
Lackey, R.T. 1997a. Seven pillars of ecosystem management. Landscape and Urban Planning, in press.
Lackey, R.T. 1997b. Challenges to using ecological risk assessment to implement ecosystem management. Water Resources Update 103: 46-49.
Lutz, F. 1902. The ecology of insect sounds. Canadian Entonomologist 34: 64-66.
Mills, L. et al. 1993. The keystone species concept in ecology and conservation. BioScience 43: 219-224.
Mitsch, W. 1993. Ecological engineering. Environmental Science and Technology 27: 438-445.
Mitsch, W. et al. 1993. Ecological engineering- contrasting experiences in China with the West. Ecological Engineering 2: 177-191.
Odum, E. 1971. Fundamentals of Ecology. Saunders.
Odum, E. 1993. Ecology and our endangered life-support systems. Sinauer.
O'Neill, R. et al. 1986. A hierarchical concept of ecosystems. Princeton University Press.
Pimental, D. 1997. US food production threatened by rapid population growth! CCN, 2000 P Street, Suite 240, Washington, DC 20038.
Pimm, S. 1997. The value of everything. Nature 387: 231-232.
Ricklefs, R. 1983. The economy of nature. Chiron Press.
Roe, E. 1996. Why ecosystem management can't work without social science: an example from the California northern spotted owl controversy. Environmental Management 20: 667-674.
Shrader-Frechette, K.S. and E.D. McCoy. 1993. Method in Ecology: Strategies
for Conservation. Cambridge University Press.
Restoration
Ecology- An Introduction
Bibliography
on the Conservation of Biological Diversity
Biodiversity
Forum
Center
for a New American Dream
Ecosystem
Services Discussion
Understanding
Ecosystem Management
Keys
to Ecosystem Management
Ecosystem
Management Fundamentals
Ecosystem
Management for Public Forests
Ecosystem
Management (Information Center for the Environment)
Ecosystem
Management at the Bureau of Land Management
National
Wildlife Federation's Homepage
Excellent
List of Ecology Links
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