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This study established the spatial footprint of the industrial trawl fishing fleet operating off southeastern and southern Brazil between 2003 and 2011. It also provides estimates of the area swept by this fleet and the correspondent Utilization Index (swept area/available area) as measures of impact over the benthic ecosystem. Lastly, costs/benefits of trawling were addressed by the cumulative biomass landed during the study period expressed as a proportion of the cumulative swept area (Biomass-Swept Area Index). These variables were mapped and their patterns of spatial-temporal variability were associated with fishing strategies (shrimp trawling, slope trawling and pair trawling), latitudinal strata, depth strata, and substrate types. The trawl fishery footprint during the study period comprised 502,190 km 2 . The total area swept by trawling operations was 680,697.5 km 2 , 1.4 times the available area. Trawling impacts on the substrate were primarily produced by the dominant shrimp trawling strategy. In comparison with other strategies, these vessels used the most extensive shelf area, and disturbed more sand/mud habitat surface to obtain less landed biomass. Delimiting the trawl fishery footprint off southeastern and southern Brazil and its main core areas comprised a first step towards in evaluating impact on such areas, providing preliminary information for future ecosystem-based fisheries management and marine spatial planning strategies.

The particle size of clastic sediments can provide important information about mechanisms of transport, selection and deposition which are related to the dominant hydrodynamic processes. This study describes the superficial sediments of ten intertidal plains located along the North (one site) and South (nine sites) Bays in Florianópolis, SC, where the clam Anomalocardia brasiliana is artisanally exploited. Systematic sedimentological sampling was carried out in all areas during the fall of 2008, summing up 464 samples. In the laboratory, samples were subjected to particle size analysis techniques. Sand was the predominant constituent in all banks analyzed, ranging from 70.59% in Maruim to 97.56% in Maciambú. Mean particle diameter varied from 1φ to 3φ in the study area, corresponding to medium to fine sands. Clay and silt attained higher percentages in Praia da Daniela bank, in North Bay, specially as compared to the banks located in the eastern and southern sectors of the South Bay. Such sediment distribution seems to be related to the more energetic characteristic of the South Bay as compared to the North Bay, where tidal and wind-induced currents are more gentle favouring the deposition of finer sediments.

Thick bay-fill sequences that often culminate in strandplain development serve as important sedimentary archives of land–ocean interaction, although distinguishing between internal and external forcings is an ongoing challenge. This study employs sediment cores, ground-penetrating radar surveys, radiocarbon dates, palaeogeographic reconstructions and hydrodynamic modelling to explore the role of autogenic processes – notably a reduction in wave energy in response to coastal embayment infilling – in coastal evolution and shoreline morphodynamics. Following a regional 2 to 4 m highstand at ca 5·8 ka, the 75 km2 Tijucas Strandplain in southern Brazil built from fluvial sediments deposited into a semi-enclosed bay. Holocene regressive deposits are underlain by fluvial sands and a Pleistocene transgressive–regressive sequence, and backed by a highstand barrier-island. The strandplain is immediately underlain by 5 to 16 m of seaward-thickening, fluvially derived, Holocene-age, basin-fill mud. Several trends are observed from the landward (oldest) to the seaward (youngest) sections of the strandplain: (i) the upper shoreface and foreshore become finer and thinner and shift from sand-dominated to mud-dominated; (ii) beachface slopes decrease from >11° to ca 7°; and (iii) progradation rates increase from 0·4 to 1·8 m yr−1. Hydrodynamic modelling demonstrates a correlation between progressive shoaling of Tijucas Bay driven by sea-level fall and sediment infilling and a decrease in onshore wave-energy transport from 18 to 4 kW m−1. The combination of allogenic (sediment supply, falling relative sea-level and geology) and autogenic (decrease in wave energy due to bay shoaling) processes drove the development of a regressive system with characteristics that are rare, if not unique, in the Holocene and rock records. These findings demonstrate the complexities in architecture styles of highstand and regressive systems tracts. Furthermore, this article highlights the diverse internal and external processes and feedbacks responsible for the development of these intricate marginal marine sedimentary systems.

Eventos extremos de precipitação influenciam a sociedade de forma direta e indireta. Dependendo de sua magnitude e extensão, os danos gerados por estes eventos podem, na maioria das vezes, ser enquadrados na categoria de desastres naturais. O objetivo deste trabalho é estabelecer e discutir valores normais e extremos para a chuva na bacia do Rio Itajaí, através da utilização da técnica estatística dos quantis, utilizando dados de precipitação das estações convencionais da Agência Nacional de Águas (ANA), no período de 1930-2013. O cálculo de frequência de classes de chuva foi realizado empregando-se as classes recomendadas pelo Instituto Nacional de Meteorologia (INMET). A análise de frequência mostrou que a classe de precipitação 0,1-2,5mm é a mais comum, com ocorrência superior a 14,5%. As classes entre 50-100mm e >100mm não chegam a ultrapassar 5% de frequência. Quanto aos anos com os maiores acumulados anuais, destacam-se os anos de 1983 e 1998 e 2008

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.

Estudos voltados para avaliação de áreas suscetíveis a movimentos de massa têm sido realizados em diversas regiões do Globo, especialmente em áreas urbanas e regiões de alta pluviosidade. O objetivo deste trabalho é analisar informações sobre movimentos de massa e extremos de precipitação na bacia do Rio Itajaí, assim como conhecer a magnitude dos eventos adversos a partir dos relatórios da Defesa Civil, através associação entre registros de deslizamento de terra disponíveis no banco de dados do Sistema Nacional de Defesa Civil e chuvas extremas. Os resultados indicaram que 42,7% dos casos de deslizamento de terra ocorreram em dias de chuvas extremas, sendo que, em 94,% dos casos, os extremos foram precedidos por dias consecutivos de chuva. O maior número de ocorrências foi registrado nos anos 2001, 2008, 2011 e 2013, principalmente na estação da primavera.

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).

Numerous methods are used to calculate indices of biotic integrity (IBI) in different regions of the world. This study used data from past works carried out at "Saco da Fazenda" (Itajai / SC) for the years 1996-2007. In addition, monthly samples of birds were held between May 2012 andApril 2013. The value obtained for the IBI matches to 27 attributes, in four degrees of degradation (Good, Regular, Poor, Very Poor). IBI was calculated for all periods to determine their variations over time. The values of IBI ranged between poor and regular throughout the sample period. In the first two years, the results ranged from poor in 1996 (2.60) to regular in 1997 (2.93) returning to the initial condition in 1998 (2.47) and 1999 (2.60). In 2000 (2.93), from 2001 to 2003 (3.00) and 2004 (3.07) IBI showed a considerable increase, indicating a regular condition of biotic integrity of the environment. But in 2005 the index was 2.87, returning to the poor category, which remained in the year 2006-2007 with a value of 2.53. Four years after the last sampling, the area remained in the poor category in the year 2012-2013 with an IBI of 2.87. The IBI is an indicator of degradation or recovery of environments over time, but caution is needed in their use, that should always be made in conjunction with other environmental indicators.

This study provides first-time estimates of direct fuel inputs and greenhouse gas emissions produced by the trawl fishing fleet operating off southeastern and southern Brazil. Analyzed data comprised vessel characteristics, landings, fishing areas and trawling duration of 10,144 fishing operations monitored in Santa Catarina State from 2003 to 2011. Three main fishing strategies were differentiated: 'shrimp trawling', 'slope trawling' and 'pair trawling'. Jointly these operations burned over 9.1 million liters of diesel to land 342.3 million kilograms of fish and shellfish. Annually, 0.023-0.031 l were consumed for every kg of catch landed. Because all fishing strategies relied on multispecific catches to raise total incomes, estimates of fuel use intensity were generally low but increased 200-900% if only nominal targets were considered. In nine years, trawling operations emitted 6.69 GgC to the atmosphere, between 2300 and 3300 tons CO2 per year.

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...

O crescimento e a expansão dos aglomerados urbanos necessitam de políticas públicas que permitam a gestão do uso e ocupação do solo, além de práticas que o viabilizem uma urbanização racional dos espaços, compatibilizando os elementos de origem antropogênica com os atributos naturais. Sistemas de Informação Geográfica têm contribuído nas pesquisas que avaliam o crescimento da urbanização sobre o ambiente natural, considerando atributos relacionados à qualidade da paisagem. Neste sentido, o objetivo deste trabalho foi avaliar as alterações na qualidade da paisagem, utilizando como parâmetro o Índice de Qualidade da Paisagem (IQP), na região do Saco da Fazenda, Itajaí/SC, entre os períodos de 1938 e 2013. Para isto foram utilizadas fotografias aéreas para os anos de 1938, 1957, 1978, 1995 e 2004, na forma de mosaicos georreferenciados, e imagens de satélite georreferenciadas para os anos de 2009 e 2013. Para a classificação das imagens foi realizada uma classificação manual, sendo utilizadas 10 classes. Os resultados do IQP (Índice de Qualidade da Paisagem) para os anos analisados foram de uma qualidade da paisagem “Média” para a área de estudo, porém numa possível replicação deste trabalho, em anos futuros, os resultados da qualidade da paisagem desta região tendem a ser alterados para a classe “Baixa”. Esta situação está relacionada a uma ampliação das classes do meio socioeconômico sobre as áreas remanescentes de vegetação herbácea, solo exposto e planície de inundação, podendo ocasionar o esgotamento da paisagem. Neste trabalho foi possível verificar as alterações na qualidade da paisagem da região avaliada, indicando uma possível degradação da mesma. Avaliações prévias da qualidade da paisagem podem contribuir para o planejamento da expansão de áreas urbanas, permitindo uma melhor adequação das intervenções, diminuindo os impactos negativos na paisagem.

This study provides first-time estimates of direct fuel inputs and greenhouse gas emissions produced by the trawl fishing fleet operating off southeastern and southern Brazil. Analyzed data comprised vessel characteristics, landings, fishing areas and trawling duration of 10,144 fishing operations monitored in Santa Catarina State from 2003 to 2011. Three main fishing strategies were differentiated: 'shrimp trawling', 'slope trawling' and 'pair trawling'. Jointly these operations burned over 141.5millionl of diesel to land 342.3millionkg of fish and shellfish. Annually, 0.36-0.48l were consumed for every kg of catch landed. Because all fishing strategies relied on multispecific catches to raise total incomes, estimates of fuel use intensity were generally low but increased 316-1025% if only nominal targets were considered. In nine years, trawling operations emitted 104.07GgC to the atmosphere, between 36,800-49,500tons CO2 per year.

The aim of this study was to understand how a stream ecosystem that flows from its fountainhead to its mouth inside a city, changes from a water resource to a point pollution source. A multidisciplinary descriptive approach was adopted, including the short-term temporal and spatial determination of physical, chemical, biological and ecotoxicological variables. Results showed that water quality rapidly decreases with increasing urbanization, leading the system to acquire raw sewage attributes even in the first hundred meters after the fountainheads. Despite the tidal circulation near the stream mouth being restricted by shallowness, some improvement of the water quality was detected in this area. The multidisciplinary evaluation showed to be useful for obtaining a more realistic understanding of the stream degradation process, and to forecast restoration and mitigation measures.

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.

The Littoral Sensitivity Index (LSI) is based on geomorphologic characteristics as the exhibition degree to the energy of the waves and tides, the steepness of the coast and the substratum type, fundamental for the determination of the impact degree and permanence of the spilled oil. Each LSI represents the sensibility of a space of the coast, and it varies of the least sensitive (1) to the most sensitive (10). The sensibility maps consist of contingency plans in case of oil spill, and could impede or reduce the caused impacts to the coastal zone. The present work had for general objective to determine the LSI to the spill of oil for southeast and south area of the State of Santa Catarina in order to integrate the project SAO Letters. For obtaining the necessary characteristics, data originated from the project SAO Letters and “field survey” was used. Later they were organized in GIS, to be classified in agreement with the proposed methodology. The computational tool used was the software ArcMap version 8.3. The resulting LSI maps are articulated in 15 Operational Maps at 1:50.000 scales. In the study area 87 segments were identified, totalizing 819,82 Km of extension. The applied methodology showed to be efficient for visualization and determination of the characteristics that distinguish different LSI.