The economic value of ecosystem services: meta-analysis and potential application of value transfer for freshwater ecosystems

In recent years, research has increasingly focused on the economic value of freshwater ecosystems, which provide essential services such as water supply, climate regulation, and recreation, but are highly vulnerable to human-induced degradation. To examine this body of work, a meta-analysis was conducted on 116 studies regarding the economic value of ecosystem services provided by freshwater ecosystems, which collectively reported 368 valuations. The results indicate that 50.2% of the variation in existing value estimates can be explained by an econometric model that controls for (a) the geographical and socio-economic characteristics of the study site, (b) the valuation method and beneficiary type, and (c) the physical and ecological attributes of the specific biome and ecosystem service. The work illustrates the effect of different freshwater ecosystems on economic valuation estimates, also showing the impact of site and socio-economic characteristics of the study. Furthermore, the study assesses the prospects for using the meta-analytic value function derived from the model, finding an average transfer error of 14.4%. This study effectively summarizes the existing literature on the economic value of freshwater ecosystems, allows for the establishment of stylized facts and provides the foundation for the development of tools to support environmental policy decisions.