Valuing ecosystem services at the urban level: a critical review

This paper critically analyses the methodologies that can be adopted to value ecosystem services (ESs) at the urban level through a literature review. While literature on ES valuation has grown in recent years, its application to urban contexts is still limited. Twenty-five papers, which include 29 different case studies, carry out an economic valuation and have undergone an in-depth analysis. The papers have been selected out of 80 papers detected through keywords. Six different valuation methodologies have been employed in the case studies. The most common ESs valued at the urban level are air quality regulation, local climate regulation, carbon sequestration and storage, and aesthetic appreciation and inspiration for culture, art, and design. The methodologies recur with different frequencies in the valuation of ESs at the urban level. Choice modeling and contingent valuation methodologies are used to value a variety of ESs, including regulating, cultural, and supporting services. Other methodologies are used to value only specific ESs. The replacement cost and damage cost avoided methodologies are used for the assessment of regulation services only; the travel cost method and contingent valuation are used for cultural services only. The results indicate that the considered valuation methodologies show different levels of appropriateness with respect to specific ES categories. Therefore, there is a need to expand the application of valuation methodologies to capture the value of all ESs provided by natural resources, in order to protect and enhance them.