Valuation of ecosystem services
Why value, what to value and what is the value?
ESS valuation has become a central theme in ecosystem services science, in particular, in the efforts to incorporate maintaining ecosystems into policy decisions on land and resource use. The following readings provide an overview of why we need to value ecosystem services, what services to value and some discussion of how as well as estimates of the value of ecosystem services.
This activity is based on the following readings:
- Ecosystem Services Factsheet
- Costanza, R., D'Arge, R. (1997) "The Value of the World's Ecosystem Services and Natural Capital" Nature 387(6630):253-261
- Blamford, A., A. Bruner, et al. (2002). "Economic Reasons for Conserving Wild Nature." Science 297(5583): 950-954.
NOTE: Questions 1, 2 & 4 form part of Assessment item 1, so suggested answers will not be available until after the assignment is submitted.
Q1 What are the main reasons given for the need to value ecosystem services?
Q2 In a table list the pro's and con's of ESS valuation.
Q3 What are some of the ways ecosystem services have been valued and at what scales? List at least 4 ways ESS have been valued and discuss the advantages and limitations of each of these procedures.
Single figure value for the worth of the majority of the earth's ecosystems (i.e. value of ESS produced, e.g. Costanza study).
Marginal or Incremental changes in the provision of ESS with changes in land-use etc.
Qualitative comparison of relative changes.
Small scale evaluation of the value of a single service in terms of if the service was lost or replacing the service (e.g. NY water catchment scenario or, replacing lost pollinators, erosion control etc on farms).
Q4 What are the practical difficulties in establishing the values of ESS (e.g. what type of data / knowledge is missing, how to measure, etc)?
Q5 Costanza and D'Arge (Costanza and d'Arge 1997) published ground breaking work on the value of the world's ecosystem services. Their paper has spurred much debate and further research into the value of ecosystem services. From the readings above, particularly Costanza and D'Arge (1997), summarise the values assigned to natural ecosystems and the services they produce.
Costanza study US$33 trillion. Include your own summary and discussion of this study and/or another study(s).
Development of Markets
One of the main ways proposed to successfully incorporate ecosystem services into decision making is to develop markets to value and trade these services.
We will return to this issue in the module 4.
Next topic - Causes & consequences of loosing ecosystem services
Topics in this module
Recommended extra reading
Heal, G. (2000) "Valuing
Ecosystem Services" Ecosystems 3(1):24-30
(This is a particularly helpful article addressing; what price reflects, the importance of marginal changes, the role of markets in valuation, and the role of valuation and incentives in conservation)
Farber, S. C., R. Costanza, et al. (2002). "Economic and Ecological
Concepts for Valuing Ecosystem Services." Ecological Economics 41:
The Ecosystem Services Project: