Indicators of Ecosystem Services Compiled by Michael Bredemeier, Forest Ecosystems Research Centre (FERC), University of Göttingen, DE mbredem@gwdg.de
Indicators of Ecosystem Services - outline • Fundamental role of ecosystem functions (EF) and services (ES) for humans • Terminology around „indicator“ (what is it?) • Indication of ecosystem services: how and why? – Examples from forest ecosystems and soils • The historical dimension – looking back on the „Wooden Age“ – Connection to indication systems relevant for biodiversity and ALTER-Net (CBD and EU headline indicators, SEBI2010, Millenium Assessment) – Towards a common indicator framework? • Attempts and limitations of (monetary) valuation • Condensed indication of ecosystem functioning and services by aggregated indices (ALTER-Net project)
A striking example how delicate and vulnerable ecosytem services are: the failed "Biosphere 2" endeavour • Eight humans enclosed in 3.15 acre closed ecosystem • With replicas of several key ecosystems • Investment of over 200 M$ • Proved impossible to supply the essential services to support the eight humans – Integrated ES „life support“ failed • Unexpected and unpleasant problems arose instead.
Terminology: EF and ES • „Ecosystem functions“ (EF) longer established and in use compared to „Ecosytem services“ (ES) • The former refer more to the natural processes and their resilience and integrity, the latter more to the benefits to humans from that. • No definite and clear distinction since many ecosystem functions directly constitute ecosystem services, e.g., water retention in soils: – Water supply to the vegetation as well as water resource provision to humans – Prevention of erosion and mitigation of flood peaks
Terminology: Indicators • „Classical“ use in science from chemistry – Any of various substances, such as litmus or phenolphthalein, that indicate the presence, absence, or concentration of another substance ... – Ecology A plant or animal whose existence in an area is strongly indicative of specific environmental conditions (thefreedictionary.com) • Should be a measurable parameter (metric or ordinal scaled) • An „index“ can be something more abstract or more aggregated.
A model of ecosystem function – service relationship valuation From: NRC (2005)
Fundamental category system for forest ecosytem functions • Cultural functions • Natural functions – Wood production – Habitat – Non-timber products • Support of biological (game, resins, herbs, diversity mushrooms ...) – Regulation of energy – Water resource and matter cycles provision • Soil protection – Recreation • Water storage and peak – Education flow control Beese 1996, and many others
The category system of the Millenium Assessment for ecosystem services (ES) • „supporting“ ecosystem services – i.e., ecosystem functions • Provisioning ES • Regulating ES • Cultural ES • + Preserving ES
Dimensions of the services obtained through plant use Species richness: vascular plants ca. 270,000 Utilized by humans Not utilized > 70,000 < 200,000 Food plants Species protection (CITES) Ca. 3,000 25,000 Medicinal In bio-prospecting Ca. 25,000 > 30,000 Medicinal plants Wood and fibre >15,000 >20,000 Ornamental Food and fibre plants > 15,000 >10,000 Source: WBGU (2004) Model plants in science Ca. 2,000
Valuation of ecosystem services .... „Many of Nature's services are literally priceless - w e cannot live w ithout them and they have no know n substitutes. "Pricing" these services can focus attention on the im portance of healthy ecosystem s.“
Arguments for valuation, starting points for communication • The world's ecosystems provide a flow of vital services, like the generation of fertile soils, purification of air and water, the mitigation of floods and drought, pollination and pest control. The world economy would crash without this "natural capital." – In this sense, the value of nature's services is infinite - we simply cannot live without them. • the value of forest services, like flood control, recycling of rainfall and carbon dioxide uptake, can be several times more valuable than timber yield. – However, the former ones are not priced ... • BD is thought to support ecosystem services – Inter alia the ability of species diversity to provide an insurance against environmental fluctuations • Economists assign values to non-marketed ecosystem services using several valuation methods.
Valuation m ethods Productivity Method: (sometimes called the net factor income or derived value method): estimates the value of ecosystem goods or services used, along with other inputs, to produce a marketed good. For example, the economic benefits of improved water quality can be measured by valuing improved crop quality and agricultural productivity. Hedonic Pricing Method: estimates values for ecosystem or environmental services that directly affect market prices, e.g. variations in housing prices reflecting local air and water quality or noise. Travel Cost Method: estimates the value of ecosystems that are used for recreation, based on how much people are willing to pay to visit the site. Dam age Cost Avoided: estimates the value of ecosystem services based on the costs of avoiding damages due to lost services. Replacem ent and Substitute Cost Method: estimates values of ecosystem services based on the cost of replacing them, or the cost of providing substitute services, e.g. valuing the water purification services of a wetland by comparing it to the cost of filtering and chemically treating water. Contingent Valuation Method: estimates values by asking people to directly state their willingness to pay for specific ecosystem services, based on a hypothetical scenario. Source: http://www.albaeco.com/sdu/06/htm/main.htm
An example of damage cost avoided • In China's Yangtze River basin, 85 percent of the original forest cover had been lost by 1998. • flooding of the river basin displaced 120 million people, causing US$30 billion worth of damage. • Chinese officials argued that standing trees were worth many times more than felled trees and banned logging in the upper reaches of the basin.
• About 15 percent of the world's energy consumption is supplied by fuelwood and other plant material – in developing countries, such "biomass" supplies nearly 40 percent of energy consumption (Hall et Further examples al. 1993) • Annual world fish catch – About 100 million metric tons – Valued between $50 and $100 billion • Medical drugs – a recent survey showed that of the top 150 prescription drugs used in the United States, 118 are based on natural sources • 74% on plants, 18% on fungi, 5% on bacteria, and 3% on one vertebrate (snake) species – commercial value of pharmaceuticals in the developed nations exceeds $40 billion per year (Principe 1989)
Ecosystem services valuation as a matter of debate • In 1997, Robert Costanza of the University of Maryland and twelve co-authors estimated the annual value of the world's ecosystem services at US$33 trillion. ( Nature 387) – This was more than the value of the global gross national product (GNP) that year! • According to Costanza, most economists would have guessed that the value of ecosystem services would only be 1 percent of global GNP or less. • Criticism: ecosystem services could never be traded in open commerce, which is how prices of conventional goods and services are determined. • Criticism: some also claim that it is not the role of science to determine what is right or wrong or to assign values based on human preferences at all. • Criticism: assigning money value only deepens the inadequate anthropocentric approach of ES („Deep Ecology“)
Conclusions / Theses • Ecosystems offer many functions and services which are indispensable for humans. – Although essential these are usually not marketed and hence not priced. • Integrity of ecosytems and their biological diversity are values per se and do not need money value as proof. • However, assigning money value can support valuation of BD and can help communicate valuation to users and the general public. • Few studies with concrete numbers available so far; easy to arrive at controversial results!
Historical excursus .... Ecosystem functions and services have been used and consumed for a long time ...
However, manifest effects emerged only with the „invention“ of agriculture and large-scale forest clearing
„Dutchmen Cuttings“
Wood demand of early Industries leads to regional deforestation From: Klose (1985)
Litter raking and humus layer removal (straw substitute)
Permanent transfer of nutrient capital (forest � arable land) N, P, Ca 2+ , Mg 2+ , K + ...
To quantitatively reconstruct biogeochemical transfers at landscape level, we have to investigate ... •Regional and local forest history � Different nutrient contents! •Land use history of the arable land •Precise course of element fluxes in the landscape over long time periods
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