Value of ecosystem services
The simplest form of ecosystem valuation for orthodox environmental economists is to hold that an ecosystem has a value equivalent to its ecological yield valued as it would be on commodity markets: for the value of water, wood, fish or game, that is purified or nurseried or generated or harboured in that ecosystem. Thus, an exchange value or 'price' is associated with the objects of value, regarded as natural capital, associated with ecosystems and this may be based on the ability of a system to produce yields each year that are exchangeable in operating markets and have existing exchange prices.
Economists and some ecologists concentrate on ecosystem services and the assignment of values in a service economy to all that Nature does "for humans" (a basic form of instrumentalism). Work based upon benefit transfer, compiled by ecologist/planner Robert Costanza in the 1990s, has claimed that even just considering the most basic seventeen of these services, the combined value of the ecosystems of the Earth was worth more (US$33T) each year; more than the whole human exchange economy (US$25T) at that time (1995). Other studies have focused on the marginal value of ecosystem changes, as advocated in orthodox economic cost-benefit analysis. In Natural Capitalism, 1999, Paul Hawken, Amory Lovins and Hunter Lovins also advanced an argument to assign a value to the planet Earth in current currency.
Mainstream environmental economists have categorized the values that should be assigned to any environmental change for which individuals are willing to pay as follows:
- direct use value attributed to direct utilisation of ecosystem services;
- indirect use value attributed to indirect utilisation of ecosystem services, through the positive externalities that ecosystems provide;
- option value attributed to preserving the option to utilise ecosystem services in the future;
- existence value attributed to the pure existence of an ecosystem.
- altruistic value based on the welfare the ecosystem may give other people.
- bequest value based on the welfare the ecosystem may give future generations.
Standard environmental economic methods are used to place a monetary value on ecosystem services where there are no market prices. These include "stated preference" methods and "revealed preference" methods. Stated preference methods, such as the contingent valuation method ask people for their willingness to pay for a certain ecosystem (service). Revealed preference methods, such as hedonic pricing and the travel cost method, use a relation with a market good or service to estimate the willingness-to-pay for the service. Applying such preference based approaches has been criticised as a means of deriving the value of ecosystems and biodiversity and for avoiding deliberation, justification and judgment in making choices.
Is valuation economics, or ecology?
Such valuation, and that of the effectiveness of various environmental health measures that affect the value of life and quality of life, are usually thought to be part of economics. Natural capital and individual capital are studied ecology as living systems, however, this does not extend to the economics of valuation by which they are related:
Considering "valuation" as an "economic not ecological issue" reflects the way these fields divide of the activities of humans versus non-humans in "making a living". When humans go out to get food or homes, that is studied in "economics", but when non-humans do it, that is "ecology", though it is clear that there are motivations, methods and certainly bodily needs in common.
Since animals do not put explicit prices on ecosystems they use, but do behave as if they are valuable, e.g. by selecting one territory vs. another, defending their territories, etc., it is mostly a matter of definition whether ecology should include valuation as an issue. It may be anthropocentric to do so, since "valuation" more clearly refers to a human perception rather than being an "objective" attribute of the system perceived. Ecology itself is also human perception, and such related concepts as a food chain are constructed by humans to help them understand ecosystems. In many cases by those who hold that markets and pricing exist independently of any individual human observers and "users", and especially those who deem markets to be "out of control", ecosystem valuation is considered a (marginal, ignored) part of economics. Others argue that natural capital is an economic concept that is at least as viable as financial capital, which itself is determined on subjective valuation. Some even suggest that valuation of ecosystem services is more cogent than financial valuation, as the ecosystem would continue after the collapse of the economy, while the inverse is not valid.
Some versions of conflict theory focus on the role of resource scarcity in sparking or propagating human conflicts - in effect holding that the resources or ecosystems they fight over are being held so valuable that they are worth considerable risk of harm to control. This is at least a relative notion of value and value at risk applied to ecosystem.
- Costanza, Robert (1997). "The value of the world’s ecosystem services and natural capital.". Nature 387.
- Spash, C.L. 2008. How much is that ecosystem in the window? The one with the bio-diverse trail. Environmental Values, vol. 17, no. 2, 259-284
- Daily, Gretchen 1997. Nature's Services. Island Press, Washington D.C., USA.
- Hanley, Nick and Clive L. Spash (1993). Cost-benefit analysis and the environment. Edward Elgar, Cheltenham.
- Pearce, David W. and R. Kerry Turner, 1990. Economics of natural resources and the environment. BPCC Wheatsons Ltd., Exeter, UK. 378 pp.
- Futehally, Ilmas. Strategic Foresight Group, India.