A região costeira do Estado de São Paulo passa por constante processo de expansão urbana, de forma, geralmente, não planejada, resultando na supressão de áreas naturais, principalmente os ambientes costeiros sensíveis, como manguezais, restingas e encostas. Em especial, a Região Metropolitana da Baixada Santista (RMBS), localizada no centro do litoral do Estado de São Paulo, sofre pressão urbana ligada à expansão das atividades econômicas na região. Nesse sentido, o presente trabalho analisou a dinâmica da expansão urbana do município de São Vicente, localizado na RMBS, entre os anos de 1963 a 2007, correlacionando-a com os ciclos econômicos e as políticas públicas regionais, com o objetivo de subsidiar o planejamento territorial e ambiental das cidades litorâneas. Para tanto, foram utilizados seis mosaicos de fotografias aéreas de cada década analisada, para o mapeamento das áreas urbanas em ambiente SIG. Os dados sobre a urbanização foram cruzados entre os anos para se obter a expansão urbana no período analisado. O maior crescimento das áreas urbanas (29,75%) foi observado no período de 1972 a 1987, intimamente ligado ao incremento de infraestrutura na região, em especial com a expansão das rodovias que ligam a capital do estado com a Baixada Santista. A área insular de São Vicente já se apresentava bastante consolidada em 1963, com expansão de núcleos urbanos ao longo do período analisado associado ao processo de favelização. A expansão urbana foi maior na área continental do que na área insular, tendo as estradas e ferrovia como vetores de ocupação. O crescimento econômico da Baixada Santista, relacionado à exploração de óleo e gás na Bacia de Santos e à expansão das atividades portuárias, poderá direcionar ainda mais o adensamento urbano para São Vicente, ameaçando os remanescentes de Mata Atlântica das Unidades de Conservação da região. O processo histórico de ocupação identificado indica uma tendência regional de drástica substituição da paisagem natural ainda existente em áreas limítrofes às Unidades de Conservação, por uma paisagem antrópica, que, provavelmente, será representada por ocupações irregulares sem infraestrutura urbana adequada para a sustentabilidade regional.
The Coastal Zone of São Paulo State (Southeast Brazil) has been under a constant process of urban expansion, which usually occurred by an unplanned way, resulting in the suppression of natural areas, especially some sensitive coastal environments such as mangroves, salt marshes and Atlantic rainforest formerly occupying hillsides and lowlands. In this sense, this study analyzed the dynamic of urban growth of São Vicente city, located on the central-south coast of São Paulo, between the years 1963 to 2007, with main concern for the urban expansion in the Coastal Zone. To achieve that, we used six mosaics of aerial photographs from each decade within the analyzed period, in order to r map the urban areas in a GIS environment. Data on urbanization were crossed between the subsequent decades to get the urban expansion in the analyzed period. We correlated the urban expansion cycles with regional public policies, with the aim of subsidize the comprehension of the territorial and environmental planning of coastal cities. The largest growth in urban areas (29.75%) was observed in the period 1972 to 1987, and was closely linked to the establishment of anthropic infra-structure (railways, roads, pipelines, electric transmission lines, among others) in the region, particularly the expansion of highways linking the state capital with the coastal cities (especially Santos, Cubatão, São Vicente, Guarujá). This period is coincident to the larger population growth within the studied timeline, when more than 76,000 inhabitants established in the city. The occupation of the island of São Vicente has already had quite consolidated in 1963, and the further expansion of urban centers during the analyzed period was associated with the process of slumming. Urban expansion was greater in the continental area, reaching to 200%, where roads and railways represented the main vectors of occupation. Territorial occupation was also influenced by the high valuation of terrains situated close to the beaches and the concentration of real state ventures, which were mostly reserved to serve as second residences for richer people, whereas poorer classes were induced to occupy mangroves, estuarine banks and hillside areas, most of them within protected or vulnerable areas. A strong correlation was observed between occupied are and population growth rates, showing that migration and arrival of new inhabitants were associated to loss of natural areas. However, the occupation speed seemed to be regulated by macroeconomic factors, in addition to the expansion of roads. The rates of population and urban growth during the last two periods were reduced in comparison to the initial periods; however, it must be highlighted that both population and urbanization presented a continuous growth, which was initially more intense. Another important factor that historically have exerted pressure on the natural areas of São Vicente is the seasonality, as fluctuating population reaches to more than 1,350 thousand people, which is almost equivalent to the resident population. The recent economic growth of Santos, related to oil and gas exploration in the Santos Basin and the expansion of port and industrial activities, may induce further urbanization for São Vicente, threatening mangroves and the remnants of Atlantic Forest from the local Protected Areas, as well as their nearby areas, which have the function of being buffer zones. Urban sprawl in coastal zones should attend the various planning instruments that are applied to rule territorial ordering and solve land use conflicts, considering the protection of natural environments from economic interests, as predicted by the Federal and State coastal management plans.
