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O objetivo deste trabalho é a análise da variação temporal da cobertura de uso e ocupação do solo de uma região estuarina no litoral centro-norte do Estado de Santa Catarina, reconstruindo as alterações na dinâmica da paisagem em um período de 75 anos (1938 - 2013), além de calcular as variações do Índice de Uso e Ocupação do Solo (IUO) e do Índice de Cobertura Vegetal (ICV). Para a classificação digital de uso e ocupação do solo foi realizada uma classificação visual, em ambiente SIG. Os resultados indicaram que nas décadas de 30, 50 e 70 ocorreram as maiores transformações na área de estudo, sendo que a variação do IUO apontou um crescimento das áreas antropizadas e o ICV demonstrou uma redução das áreas com vegetação. Estudos desta natureza constituem-se ferramentas importantes para a tomada de decisão dos gestores municipais, na busca de um crescimento mais harmônico das cidades, compatibilizando as necessidades dos moradores por moradias e serviços públicos com os remanescentes naturais, que tem igual importância para a qualidade de vida da população.

Inúmeros métodos são utilizados para calcular índices de integridade biótica (IIB) em diferentes regiões do mundo. Esse trabalho teve por objetivo calcular o índice de Integridade Biótica (IIB), para uma área estuarina no Sul do Brasil, a partir de dados da comunidade de peixes e avaliar suas flutuações ao longo dos anos. Neste estudo foram estabelecidos quatro pontos para amostragem da ictiofauna, no estuário Saco da Fazenda em Itajaí-SC, em coletas mensais realizadas entre maio/2012 a abril/2013. As amostras foram triadas e os espécimes identificados até o nível taxonômico de espécie. O valor obtido para o Índice de Integridade Biótica incluiu 11 atributos, em quatro graus de degradação ao longo de um ano de amostragem. Os valores do IIB foram calculados e classificados em diferentes níveis para reconhecer suas variações temporais e espaciais. Foi calculado também o IIB utilizando os dados históricos (2000 a 2005), para mostrar as alterações em comparação com as investigações de campo recentes. O resultado para os anos de 2000-2002 indica uma integridade biótica pobre, sendo regular para os anos de 2003-2005 e regredindo para pobre nos anos de 2012-2013.

Clastic, depositional strandplain systems have the potential to record changes in the primary drivers of coastal evolution: climate, sea-level, and the frequency of major meteorological and oceanographic events. This study seeks to use one such record from a southern Brazilian strandplain to highlight the potentially-complex nature of coastal sedimentological response to small changes in these drivers. Following a 2 to 4 m highstand at ca 5·8 ka in southern Brazil, falling sea-level reworked shelf sediment onshore, forcing coastal progradation, smoothing the irregular coastline and forming the 5 km wide Pinheira Strandplain, composed of ca 500 successive beach and dune ridges. Sediment cores, grab samples and >11 km of ground-penetrating radar profiles reveal that the strandplain sequence is composed of well-sorted, fine to very-fine quartz sand. Since the mid-Holocene highstand, the shoreline prograded at a rate of ca 1 to 2 m yr−1 through the deposition of a 4 to 6 m thick shoreface unit; a 1 to 3 m thick foreshore unit containing ubiquitous ridge and runnel facies; and an uppermost beach and foredune unit. However, the discovery of a linear, 100 m wide barrier ridge with associated washover units, a 3 to 4 m deep lagoon and 250 m wide tidal inlet within the strandplain sequence reveals a period of shoreline transgression at 3·3 to 2·8 ka during the otherwise regressive developmental history of the plain. The protected nature of Pinheira largely buffered it from changes in precipitation patterns, wave energy and fluvial sediment supply during the time of its formation. However, multiple lines of evidence indicate that a change in the rate of relative sea-level fall, probably due to either steric or ice-volume effects, may have affected this coastline. Thus, whereas these other potential drivers cannot be fully discounted, this study provides insights into the complexity of decadal-scale to millennial-scale coastal response to likely variability in sea-level change rates.

This paper presents a comprehensive review on the interaction between hydrodynamic processes, beach morphology and sedimentology at large scale coastal behaviour along the coastline of Santa Catarina, between Laguna and Sao Francisco Island, a microtidal east coast swell environment with headland and bay geomorphologies. The parabolic bay shape equation has proven to be a convenient and practical tool for studying the stability of the headland-bay beaches, tombolos, and salients in Santa Catarina. The beaches exhibit different patterns of sediment removal as a function of the degree of beach curvature. In highly curved beaches, there is a well-developed shadow zone and a range of morphodynamic conditions, from a sheltered low-energy beach adjacent to the downdrift headland to a high-energy exposed beach on the straight end of the headland-bay beach. The less curved beaches instead, tend to show more uniform behaviour since they are directly exposed to incident waves. There is no obvious relationship between average wave height and mean grain size, showing the importance of sediment source to characterize the sedimentary distribution patterns in the study area. The analysis of beaches showed that beach morphodynamics and sequence profiles for a bay–headland coast in a microtidal east coast environment is a function of geological inheritance (e.g., distance between headlands and orientation, nearshore and inner shelf morphology, coastal plain morphology, and sediment source), and hydrodynamic factors (wave conditions, oceanic wave exposure and relative tidal range).

Shoreline salients are low triangular landforms, which project seaward as promontories. The term tombolo is applied when this landform is joined to an island or obstacle. This work presents a literature review of salients and tombolos, with a classification of singular landforms, and discusses the relationships between morphological parameters. It also analyses the planform of these features (sigmoid model and parabolic model) on the coast of the State of Santa Catarina in the south of Brazil. Interpretation of aerial photographs and topographical maps enabled the identification of 15 tombolos and 10 salients. The observed proportions and the symmetry of these landforms are directly related to the geological conditions and predominant wave direction. For salience data, regressions between X/B and B/S presented an R2 of 0.79. Regressions between the obstacle depth (d) and the average length of incident waves were obtained, and the results (B*d / (L2) ~ S*d / (L2)) exhibited high R2 values (0.83 an...

This work has applied an integrated method for defining set-back lines associated with coastal hazards on sandy shores for a 50-year period of interest. This method is based on the shoreline evolutionary trend being the basis for the first set-back line determination. Afterwards the set-back line were adjusted by incorporating changes associated with the acceleration of sea-level rise and the evaluation of the consequences (instantaneous shoreline retreat and potential flood zone) of an extreme storm. The study area was Itapocoroi Bay, in northern coast of Santa Catarina State, southern Brazil. The determined set-back lines were plotted over rectified aerial photographs, allowing for a straight-forward interpretation of results. The segments northward of Picarras river mouth and right before the Itajuba headland were the most susceptible zones due coastal hazard mentioned. The integrated method showed to be an important tool for coastal management since it adopts a worst-case scenario approach.