Interações entre evolução sedimentar e ocupação humana pré-histórica na costa centro-sul de Santa Catarina, Brasil

Desde o começo da ocupação humana no litoral centro-sul de Santa Catarina, Brasil, a articulação entre processos naturais e antrópicos modelou uma paisagem fortemente domesticada, marcada pela construção massiva de concheiros de dimensões monumentais e pela permanência milenar. Na planície costeira entre Passagem da Barra (município de Laguna) e lago Figueirinha (município de Jaguaruna), 76 sambaquis foram mapeados, dos quais 48 possuem datação. O levantamento sistemático de sítios e datações permitiu identificar padrões de distribuição espacial nos sambaquis da região, quanto a contexto sedimentar da época de construção, estratigrafia e idade. Desse modo, reconheceram-se nos sítios da região: cinco contextos geológico-geomorfológicos de localização; três padrões estratigráficos; e quatro fases de ocupação sambaquieira baseadas na quantidade de sítios e no tipo de padrão construtivo dominante. O modelo integrado de evolução sedimentar e distribuição tempo-espacial de sambaquis indica que estes sítios eram construídos em áreas já emersas e pouco alagáveis, e que sítios interiores, afastados dos corpos lagunares, podem não se ter preservado ou não estarem expostos devido ao processo de assoreamento contínuo que caracterizou a região após a máxima transgressão holocênica. O cruzamento de dados aqui proposto evidencia a importância de abordagens integradas entre arqueologia e geociências no estudo da evolução das paisagens.

As relações entre construção da imagem corporal, função paterna e hiperatividade: reflexões a partir da Pesquisa IRDI

A partir da psicanálise, 31 indicadores clínicos de risco para o desenvolvimento infantil (IRDI) foram construídos e aplicados em 727 crianças entre 0 e 18 meses. Uma subamostra de 280 crianças foi avaliada com a idade de três anos. Uma primeira análise de resultados mostra uma relação entre imagem do corpo, dificuldade de separação, agitação motora e vínculos corporais estreitos com as mães. Esses resultados são discutidos criticamente à luz da noção atual de hiperatividade.

A dimensão criadora no trabalho docente: subsídios para a formação de professores alfabetizadores

Este artigo tem como objetivo evidenciar a dimensão criadora dos saberes docentes mobilizados por uma professora alfabetizadora, a partir da concepção de saberes docentes desenvolvida pela teoria histórico-cultural. A pesquisa realizou-se em escola pública, no estado de Rondônia, por meio de uma abordagem etnográfica. O trabalho traz para a análise duas cenas recortadas do cotidiano escolar para exemplificar como os saberes docentes são alterados e recriados no enfrentamento dos desafios impostos pela prática pedagógica. Os resultados permitem compreender que a prática docente no cotidiano não se caracteriza apenas como reprodução de modelos ou propostas utilizadas por outros profissionais. Ao contrário, no encontro de uma professora e uma turma de alunos há sempre certa originalidade que demanda a criação de formas específicas de intervenção para aquele grupo, nas condições do contexto. Acompanhar o trabalho da professora durante o período de pesquisa permitiu compreender que há inúmeras possibilidades de condução do trabalho pedagógico e as razões que motivam as escolhas dos professores e das professoras estão fundamentadas em saberes construídos ao longo de suas experiências de formação e atuação. Considera-se, portanto, que as práticas pedagógicas precisam ser conhecidas e estudadas para que se possa compreendê-las, mais do que avaliá-las, tendo-se em vista a contribuição desses estudos para a formação docente.

Headland-bay beach planform stability of Santa Catarina State and of the Northern Coast of São Paulo State

This paper presents the results of the planform stability classification for the headland-bay beaches of the State of Santa Catarina and of the Northern Coast of São Paulo, based on the application of the Parabolic Bay-Shape Equation (PBSE) to aerial images of the beaches, using the software MEPBAY®. For this purpose, georeferenced mosaics of the QuickBird2® satellite imagery (for the State of Santa Catarina) and vertical aerial photographs (for the northern coast of São Paulo State) were used. Headland-bay beach planform stability can be classified as: (1) in static equilibrium, (2) in dynamic equilibrium, (3) unstable or (4) in a state of natural beach reshaping. Static equilibrium beaches are the most frequent along the coast of the State of Santa Catarina and the Northern Shore of São Paulo, notably along the most rugged sectors of the coast and those with experiencing lower fluvial discharge. By comparison, dynamic equilibrium beaches occur primarily on the less rugged sectors of the coast and along regions with higher fluvial discharge. Beaches in a state of natural beach reshaping have only been found in SC, associated with stabilized estuarine inlets or port breakwaters. However, it is not possible to classify any of these beaches as unstable because only one set of images was used. No clear relation was observed between a beach's planform stability and other classification factors, such as morphodynamics or orientation.

O sexo sem lei, o poder sem rei: sexualidade, gênero e identidade no cotidiano travesti

Neste trabalho propomos questionar como são construídos e validados os discursos acerca de sexualidade, gênero e identidade sexual, a partir da história de vida de três irmãos homossexuais nascidos no interior do nordeste brasileiro. Ainda jovens, migraram para a cidade de Diadema - São Paulo, onde se tornaram, no decorrer de alguns anos, travestis e profissionais do sexo. A percepção da homossexualidade foi relatada como parte da infância, e sentida como uma força natural. Já, as transformações realizadas sobre o corpo decorrentes da travestilidade, a decisão pela prostituição, a orientação sexual (por homem ou por mulher), e a construção de uma identidade sexual (gay ou travesti), apareceram como instâncias dissociadas entre si e relacionadas à busca da valorização pessoal e social diante do estigma atribuído ao gay afeminado, pobre e migrante. A religiosidade afro-brasileira e a gramática yorubá assumiram relevância para a constituição desta possibilidade identitária.

Consumo e comportamento alimentar entre adolescentes brasileiros: Pesquisa Nacional de Saúde do Escolar (PeNSE), 2009

O objetivo deste artigo é descrever características de consumo e comportamento alimentar de adolescentes brasileiros e sua associação com fatores sociodemográficos. Estudou-se, em 2009, amostra representativa de alunos do 9º ano do ensino fundamental de escolas públicas e privadas das 26 capitais brasileiras e do Distrito Federal. Utilizou-se questionário autoaplicável sobre atributos sociodemográficos, consumo e comportamento alimentar, entre outros. Estimativas dos indicadores construídos foram apresentadas para o total da população e por sexo. A associação de cada um dos indicadores com variáveis sociodemográficas foi examinada por meio de regressão logística. A maioria dos adolescentes consumia regularmente feijão (62,6%), leite (53,6%) e guloseimas (50,9%), realizava pelo menos o almoço ou o jantar com a mãe ou responsável (62,6%) e comia assistindo televisão ou estudando (50,9%). Em geral, as meninas estavam mais expostas a práticas alimentares não desejáveis, e o melhor nível socioeconômico associou-se a maiores prevalências dos indicadores estudados. Os resultados revelaram consumo regular dos marcadores de alimentação não saudável e consumo inferior ao recomendado dos de alimentação saudável, apontando a necessidade de ações de promoção de saúde dirigidas a jovens.

Physical controls on carbon dioxide transfer velocity and flux in low-gradient river systems and implications for regional carbon budgets

Outgassing of carbon dioxide (CO(2)) from rivers and streams to the atmosphere is a major loss term in the coupled terrestrial-aquatic carbon cycle of major low-gradient river systems (the term ""river system"" encompasses the rivers and streams of all sizes that compose the drainage network in a river basin). However, the magnitude and controls on this important carbon flux are not well quantified. We measured carbon dioxide flux rates (F(CO2)), gas transfer velocity (k), and partial pressures (p(CO2)) in rivers and streams of the Amazon and Mekong river systems in South America and Southeast Asia, respectively. F(CO2) and k values were significantly higher in small rivers and streams (channels <100 m wide) than in large rivers (channels >100 m wide). Small rivers and streams also had substantially higher variability in k values than large rivers. Observed F(CO2) and k values suggest that previous estimates of basinwide CO(2) evasion from tropical rivers and wetlands have been conservative and are likely to be revised upward substantially in the future. Data from the present study combined with data compiled from the literature collectively suggest that the physical control of gas exchange velocities and fluxes in low-gradient river systems makes a transition from the dominance of wind control at the largest spatial scales (in estuaries and river mainstems) toward increasing importance of water current velocity and depth at progressively smaller channel dimensions upstream. These results highlight the importance of incorporating scale-appropriate k values into basinwide models of whole ecosystem carbon balance.

Land-Water interactions in the amazon

Biogeochemistry is hosting this special thematic issue devoted to studies of land-water interactions, as part of the Large-scale Biosphere-Atmosphere Experiment in Amaznia (LBA). This compilation of papers covers a broad range of topics with a common theme of coupling land and water processes, across pristine and impacted systems. Findings highlighted that hydrologic flowpaths are clearly important across basin size and structure in determining how water and solutes reach streams. Land-use changes have pronounced impacts on flowpaths, and subsequently, on stream chemistry, from small streams to large rivers. Carbon is produced and transformed across a broad array of fluvial environments and wetlands. Surface waters are not only driven by, but provide feedback to, the atmosphere.

Small rivers in the southwestern Amazon and their role in CO(2) outgassing

A recent estimate of CO(2) outgassing from Amazonian wetlands suggests that an order of magnitude more CO(2) leaves rivers through gas exchange with the atmosphere than is exported to the ocean as organic plus inorganic carbon. However, the contribution of smaller rivers is still poorly understood, mainly because of limitations in mapping their spatial extent. Considering that the largest extension of the Amazon River network is composed of small rivers, the authors` objective was to elucidate their role in air-water CO(2) exchange by developing a geographic information system ( GIS)- based model to calculate the surface area covered by rivers with channels less than 100 m wide, combined with estimated CO(2) outgassing rates at the Ji-Parana River basin, in the western Amazon. Estimated CO(2) outgassing was the main carbon export pathway for this river basin, totaling 289 Gg C yr(-1), about 2.4 times the amount of carbon exported as dissolved inorganic carbon ( 121 Gg C yr(-1)) and 1.6 times the dissolved organic carbon export ( 185 Gg C yr(-1)). The relationships established here between drainage area and channel width provide a new model for determining small river surface area, allowing regional extrapolations of air - water gas exchange. Applying this model to the entire Amazon River network of channels less than 100 m wide ( third to fifth order), the authors calculate that the surface area of small rivers is 0.3 +/- 0.05 million km(2), and it is potentially evading to the atmosphere 170 +/- 42 Tg C yr(-1) as CO(2). Therefore, these ecosystems play an important role in the regional carbon balance.

Mean sea-level rise impacts on Santos Bay, Southeastern Brazil - physical modelling study

The greenhouse effect and resulting increase in the Earth`s temperature may accelerate the mean sea-level rise. The natural response of bays and estuaries to this rise, such as this case study of Santos Bay (Brazil), will include change in shoreline position, land flooding and wetlands impacts. The main impacts of this scenario were studied in a physical model built in the Coastal and Harbour Division of Hydraulic Laboratory, University of Sao Paulo, and the main conclusions are presented in this paper. The model reproduces near 1,000 km(2) of the study area, including Santos, Sao Vicente, Praia Grande, Cubatao, Guaruja and Bertioga cities.

A framework for selecting appropriate remotely sensed data dimensions for environmental monitoring and management

Two major factors are likely to impact the utilisation of remotely sensed data in the near future: (1)an increase in the number and availability of commercial and non-commercial image data sets with a range of spatial, spectral and temporal dimensions, and (2) increased access to image display and analysis software through GIS. A framework was developed to provide an objective approach to selecting remotely sensed data sets for specific environmental monitoring problems. Preliminary applications of the framework have provided successful approaches for monitoring disturbed and restored wetlands in southern California.

Soil morphological control on saline and freshwater lake hydrogeochemistry in the Pantanal of Nhecolandia, Brazil

Joint pedological, geochemical, hydrological and geophysical investigations were performed to study the coexistence or saline and freshwater lakes in close proximity and similar climatic conditions in the Nhecolandia region, Pantanal wetlands in Brazil. The saline lakes are concentrically surrounded by green sandy loam horizons, which cause differential hydrological regimes. Mg-calcite, K-silicates, and amorphous silica precipitate in the soil cover, whereas Mg-silicates and more soluble Na-carbonates are concentrated in the topsoil along the shore of the saline lake. In saline solutions, some minor elements (As, Se) reach values above the water quality recommendations, whereas others are controlled and incorporated in solid phases (Ba, Sr). Locally, the destruction of the sandy loam horizons generates very acidic soil solution (pH similar to 3.5) through a process not yet understood. The soil distributions indicate that some freshwater lakes are former saline lakes. They are invaded by freshwater after destruction of the sandy loam green horizons, then the freshwater becomes enriched in K(+), SO(4)(2-), Fe, Al, and a stream of minor and trace elements. The formation of these green sandy loam horizons in the saline environment and their destruction in the non-saline one emphasizes the dynamic nature of this environment (C) 2008 Elsevier B.V. All rights reserved.

An evaluation of the evidence for linkages between mangroves and fisheries: A synthesis of the literature and identification of research directions

There is a widely held paradigm that mangroves are critical for sustaining production in coastal fisheries through their role as important nursery areas for fisheries species. This paradigm frequently forms the basis for important management decisions on habitat conservation and restoration of mangroves and other coastal wetlands. This paper reviews the current status of the paradigm and synthesises the information on the processes underlying these potential links. In the past, the paradigm has been supported by studies identifying correlations between the areal and linear extent of mangroves and fisheries catch. This paper goes beyond the correlative approach to develop a new framework on which future evaluations can be based. First, the review identifies what type of marine animals are using mangroves and at what life stages. These species can be categorised as estuarine residents, marine-estuarine species and marine stragglers. The marine-estuarine category includes many commercial species that use mangrove habitats as nurseries. The second stage is to determine why these species are using mangroves as nurseries. The three main proposals are that mangroves provide a refuge from predators, high levels of nutrients and shelter from physical disturbances. The recognition of the important attributes of mangrove nurseries then allows an evaluation of how changes in mangroves will affect the associated fauna. Surprisingly few studies have addressed this question. Consequently, it is difficult to predict how changes in any of these mangrove attributes would affect the faunal communities within them and, ultimately, influence the fisheries associated with them. From the information available, it seems likely that reductions in mangrove habitat complexity would reduce the biodiversity and abundance of the associated fauna, and these changes have the potential to cause cascading effects at higher trophic levels with possible consequences for fisheries. Finally, there is a discussion of the data that are currently available on mangrove distribution and fisheries catch, the limitations of these data and how best to use the data to understand mangrove-fisheries links and, ultimately, to optimise habitat and fisheries management. Examples are drawn from two relatively data-rich regions, Moreton Bay (Australia) and Western Peninsular Malaysia, to illustrate the data needs and research requirements for investigating the mangrove-fisheries paradigm. Having reliable and accurate data at appropriate spatial and temporal scales is crucial for mangrove-fisheries investigations. Recommendations are made for improvements to data collection methods that would meet these important criteria. This review provides a framework on which to base future investigations of mangrove-fisheries links, based on an understanding of the underlying processes and the need for rigorous data collection. Without this information, the understanding of the relationship between mangroves and fisheries will remain limited. Future investigations of mangrove-fisheries links must take this into account in order to have a good ecological basis and to provide better information and understanding to both fisheries and conservation managers.

Hydraulic tracer studies in a pilot scale subsurface flow constructed wetland

Current design procedures for Subsurface Flow (SSF) Wetlands are based on the simplifying assumptions of plug flow and first order decay of pollutants. These design procedures do yield functional wetlands but result in over-design and inadequate descriptions of the pollutant removal mechanisms which occur within them. Even though these deficiencies are often noted, few authors have attempted to improve modelling of either flow or pollutant removal in such systems. Consequently the Oxley Creek Wetland, a pilot scale SSF wetland designed to enable rigorous monitoring, has recently been constructed in Brisbane, Australia. Tracer studies have been carried out in order to determine the hydraulics of this wetland prior to commissioning it with sealed sewage. The tracer studies will continue during the wetland's commissioning and operational phases. These studies will improve our understanding of the hydraulics of newly built SSF wetlands and the changes brought on by operational factors such as biological films and wetland plant root structures. Results to date indicate that the flow through the gravel beds is not uniform and cannot be adequately modelled by a single parameter, plug flow with dispersion, model. We have developed a multiparameter model, incorporating four plug flow reactors, which provides a better approximation of our experimental data. With further development this model will allow improvements to current SSF wetland design procedures and operational strategies, and will underpin investigations into the pollutant removal mechanisms at the Oxley Creek Wetland. (C) 1997 IAWQ. Published by Elsevier Science Ltd.

Effects of habitat characteristics and climate on the distribution and colouration of Dusky Moorhens (Gallinula tenebrosa) in south-east Queensland

We determined which factors predict the presence and abundance of Dusky Moorhens (Gallinula tenebrosa) at wetlands by surveying the ecological and habitat characteristics of 62 sites across south-east Queensland. Moorhens were observed in 48 of the sites sampled. They were more likely to be found at sites surrounded by taller terrestrial vegetation and where free-floating and attached aquatic vegetation was more abundant. The number of moorhens found at a site increased in relation to vegetation height, the abundance of attached aquatic vegetation and the number of purple swamphens observed. These results suggest that there are ecological constraints on the distribution of moorhens, and that food abundance and the availability of suitable nesting sites determine the overall distribution and abundance of moorhens in wetlands. Adult moorhens develop brightly coloured fleshy frontal shields, bills and legs when breeding, although in some populations birds maintain year-round colouration. We observed year-round breeding colouration in 23 out of 34 sampling sites that had moorhens and were surveyed in August. Coloured moorhens were found during winter at sites with higher minimum winter temperatures, and more abundant free-floating and submerged leafy vegetation. In addition, higher proportions of moorhens were coloured at sites with higher mean minimum temperatures. The retention of year-round breeding colouration appears to be restricted to areas with warmer winter temperatures and more abundant food. The results suggest that areas not occupied by moorhens are of inadequate quality to support breeding populations. We suggest that ecological constraints on independent breeding in Dusky Moorhens may have favoured the evolution of their unusual cooperative breeding system, which involves frequent mate-sharing by both sexes.