Effects of urban sprawl on the reduction of environmental quality in the Rocuant-Andalién wetland between 2004 and 2022

Abstract

This study analyzes the impact of urbanization on the environmental quality of the Rocuant-Andalién wetland between 2004 and 2022. The methodology includes estimating the reduction of wetland area using Landsat satellite images for the years 2004, 2010, 2016, and 2022, and assessing changes in environmental quality through a multicriteria analysis. This work complements the study conducted by Smith and Romero (2009) for the Metropolitan Area of Concepción (AMC) during the period 1975–2004, allowing for continued monitoring of the trend of environmental degradation linked to urban expansion observed by those authors.

The results show a sustained decrease in both wetland area and environmental quality, particularly in the southern sector, although the loss of area is not always proportional to the level of degradation. The general trend of environmental deterioration identified between 1975 and 2004 persists during 2004–2022 but is not constant. Compared with the findings of Smith and Romero, different trends were observed, with the 2000s identified as the decade of greatest deterioration.

It was concluded that although the reduction in area affects environmental quality, this relationship is not always proportional, as other factors such as urbanization patterns and climatic variables also play a role. Furthermore, although the deterioration trend has slowed, degradation could intensify again due to the lack of legal protection and the classification of much of the wetland as developable land under the Concepción Metropolitan Regulatory Plan (PRMC). Conserving this wetland is crucial because of the ecosystem services it provides, which are essential for urban quality of life.