Ecosystem services of blue-green infrastructure (BGI) for climate change adaptation and mitigation in an arid region

Urban rivers are blue-green infrastructures of great importance due to their multiple ecosystem services which strengthen habitat connectivity and biodiversity. Cities in arid regions are vulnerable to climate change and face several problems: Inadequate response to floods; scarce availability of water resources; river pollution; urban landscape transformation; and urban heat island effect. Arequipa, an arid city in south Peru, has an urban section along the Chili River which flow allows the development of energy and agricultural activities; however, there is a gradual loss of the corridor due to environmental phenomena and anthropic alterations. The aim is to evaluate the ecosystem services offered by the urban river, which will allow a holistic understanding of its potential as a measure for climate change adaptation and mitigation. The main ecosystem services were determined through an evaluation (surveys) by national and international experts. Afterwards, based on a bibliographic review, the ecosystem services determined were associated with their capacity for adaptation or mitigation of climate change in Arequipa. The results of the surveys showed that the most important ecosystem service provided by an urban river is environmental education, which is considered fundamental for participatory governance involving multiple stakeholders. The main ecosystem service provided by the Chili River is the freshwater provision. Most of the ecosystem services contribute to climate change adaptation; however, air quality regulation and air purification through carbon capture and storage were identified as mitigation mechanisms. It is concluded that the preservation of the urban river and its ecosystem services contribute to increasing the overall level of resilience of the city. Management of this ecosystem, based on the recognition of the ecosystem services that urban rivers provide, will be essential considering the value of this type of blue-green infrastructure as a strategy for adaptation and mitigation of climate change.