A new paper published in the journal Sustainability presents the values of three ecosystem services – water filtration, nutrient cycling, and carbon sequestration – in the Grand River watershed of southern Ontario, Canada. The paper’s first author, Tariq Aziz, is a former ERG PhD student. His co-authors are Alian-Désiré Nimubona from the Department of Economics at Waterloo and Philippe Van Cappellen.
The study compares valuation estimates based on locally derived (i.e., specific to the Grand River watershed) unit values to valuations based on unit values from a regional database and those compiled in the global Ecosystem Services Valuation Database (ESVD). The regional database yields average monetary values for the three ecosystem services that are close to those obtained with the local unit values but are associated with higher uncertainties. ESVD, however, yields significantly higher monetary values for the ecosystem services. For water filtration, the ESVD derived value is more than five times higher than the regional and local estimates. The results emphasize the importance of critically assessing the origin of unit values, especially when ecosystem services valuation is used as a policy-guiding tool.
The paper is published as open access and can be found at: