Assessing an Ecological Revitalization Project of Urban Streams in Brazilian Southeastern Region by Analytic Hierarchy Process

Abstract

Worldwide, rivers have been severely degraded (chemically, morphologically, and biologically) due the unplanned system of land cover change, especially urban expansion. There is a huge necessity to restore or revitalize the rivers, and the natural-based solution approach might be an interesting alternative to do this. Our goal was evaluating the performance of structures (jute-based bags and geo-textile-based barriers) installed in stretches of degraded urban streams to facilitate revitalization. We assessed the outcomes through a set of ecological indicators, which consisted of data obtained in the field or laboratory (after analysis of samples collected in situ). We applied the analytic hierarchy process (AHP) approach to conjointly analyze ecological and opinion information. By the AHP approach, we successfully ranked the essential characteristics of the proposals. It then made it possible to identify the most successful proposal among the evaluation criteria previously defined by the team. We concluded that the best alternative was the implantation of structures (bags) that provoked local favorable ecological changes and provided conditions for the emergence and growth of vascular plants, which, in turn, provided conditions for the appearance of invertebrate animals. Furthermore, local residents were compassionate to the installation of the structures. The AHP, having the potential to gather several decisive features of nuanced elements those other methods would not be able to reveal approach, was a crucial approach to identify and choose precisely, and in an integrated manner, the best alternative for the revitalization of the river. We recommend using the AHP approach in environmental restoration projects.