Onema

Home - Mission - A Four Part Strategy

Why put a price on the services rendered by wetlands?

The economic assessment of services rendered by wetlands highlights the value of their preservation.


The recent debates on controversial development projects (airport at Notre-Dame-des-Landes, Sivens dam, Chambaran forest, etc.) have placed a spotlight on the issues involved in preserving wetlands. On a regular basis, people speak up to remind us that flood damage is made worse by the disappearance of wetlands. Unfortunately, the discussions often focus solely on the opposition between economic development and environmental protection. Economic assessments of the services rendered by wetlands could play an important role in the public debates by showing that these environments are a source of economic wealth.

Assessing the services rendered

For a number of years, it has been acknowledged that correctly functioning wetlands provide human societies with important services. The categories proposed by studies on “ecosystem services” highlight their value. In the framework of the Millennium Ecosystem Assessment (MEA), from 2001 to 2005 a UN programme, involving over 1 000 experts, listed four main types of services provided by ecosystems, namely 1) provisioning services (supply of wood, energy, medicinal substances, etc.), 2) regulating services (notably for water and the climate), 3) cultural services and finally 4) supporting services that are necessary for the production of the other services. Since then, a large number of studies have attempted to economically assess these services, always paying great attention to wetlands, notably the work by the Sustainable-development division of the Ecology ministry (CGDD) on “Assessing the benefits of changes in water quality” in 2014 and the current project for the French assessment of ecosystems and ecosystem services (EFESE). In parallel, studies are conducted on the local level, e.g. the CGDD study on the Bassée alluvial plain in 2012 and the study by the Loire-Bretagne water agency on seven types of wetlands in the basin.

Agreeing on the method

It is, however, far from easy to translate into euros the services provided by wetlands to society. Knowledge on these environments and the corresponding uses is an indispensable prerequisite, but is often lacking. But above all, there are many questions on how to assess the services, e.g. what method can be used to avoid double or triple counting of certain services? How can changes in the conservation status of wetlands be accounted for, given that the level of service provided depends on the overall quality of these natural environments? Which economic assessment method should be employed? How can the beneficiaries of services be identified? In that the choice of methods influences the assessment results, one of the main objectives must be to standardise the methods.

The limits to monetising ecosystem services

Monetisation, i.e. the actual price setting, is often the most eagerly awaited step in these studies. For example, the services provided by one hectare of wetlands in the Bassée plain were calculated in 2010 to represent at least 1 300 to 6 700 euros per year. This means that if these wetlands are damaged, society would lose at least part of this “annual income”. In public debates, this information clearly highlights the value of preserving these aquatic environments and is useful in showing that the destruction of wetlands incurs a cost for humans. The assumption underlying most economic assessments is that they can rebalance decision-making processes in favour of environmental protection. That being said, they must nonetheless be used with circumspection and caution. It would be counter-productive if they resulted in only the useful and “profitable” wetlands being saved. Certainly other “values” should encourage us to preserve wetlands.

Contact:

  • pierre.caessteker@onema.fr
  •  

     

    Back to Newsletter