Urban and land use and land cover transformation patterns in the North Coast: the case of Osório, Tramandaí, and Imbé

Abstract

The article investigates the patterns of urban transformation and land use and cover in the North Coast of Rio Grande do Sul (Litoral Norte do Rio Grande do Sul), focusing on the municipalities of Osório, Tramandaí, and Imbé. Located in the North Coast Urban Agglomeration (Aglomeração Urbana do Litoral Norte - AULINOR), these municipalities illustrate different dynamics of population growth, urban expansion, and land use and cover between 1985 and 2023. The North Coast region of Rio Grande do Sul stands out for having the highest population growth in the state, registering an increase of 25.8% between 2010 and 2022. Using data from IBGE and MapBiomas, the analysis reveals an intense process of urbanization driven by tourist attraction and permanent migration. The total urbanized area of AULINOR expanded by 60% during this period (increasing from 112 km2 in 1985 to 180 km2 in 2023), resulting in densification, sprawl, and conurbation. Osório stands out as a regional center with sprawling urban growth, while Tramandaí is a consolidated tourist center with dense and continuous urbanization. Imbé, a seasonal tourist center, presented the most accelerated population growth, multiplying its population by 3.6 times between 1991 and 2022, with occupation advancing over sensitive ecosystems, such as dunes and restingas (coastal scrub/dune vegetation). The study reinforces the need for integrated territorial and environmental management policies, with regionalized solutions, especially in conurbated contexts. Spatial modeling and the use of open data prove to be strategic tools to support sustainable urban planning, strengthening governance and public action regarding the impacts of coastal urbanization.