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A study on sediment surface diatom composition in relation to both protein/carbohydrate content and salinity was carried out in Montevideo Bay and the adjacent coastal zone. Samples were seasonally taken during one year along a human impact gradient, and the trophic conditions were assessed from the biochemical composition of the surface sediment organic matter. The co-occurrence of the marine-brackish (Actinocyclus curvatulus, Actinocyclus gallicus, Coscinodiscus excentricus, Coscinodiscus radiatus, Hyalodiscus subtilis, Paralia sulcata) and freshwater diatom flora (Aulacoseira granulata, Aulacoseira italica, Aulacoseira muzzanensis, Actinocyclus normanii, Amphora copulata, Cyclotella meneghiniana, Nitzschia linearis), suggests myxohaline estuarine conditions in the study area. The sampling stations located within the bay, close to several contamination sources, exhibited hypertrophic conditions as indicated by the highest levels of protein content, but also by the high relative abundances of Actinocyclus normanii and Cyclotella meneghiniana, as both diatom species are very well established cosmopolitan proxies of aquatic degradation. The levels of both protein and carbohydrate content, but also photosynthetic pigments, recorded in the adjacent coastal zone suggest meso-eutrophic conditions as contamination levels from the inner bay might become diluted off shore. Multivariate diatom species-environmental data relationships, indicate that the trophic gradient is hierarchically more important than salinity in explaining the diatom distribution. The present data imply an improvement in our ability of assessing organic contamination in the study area, since both biological and biopolymer variables were introduced for the first time as a tool for assessing the benthic health/degradation in one of the most populated regions of the Río de la Plata.Foi realizado um estudo da salinidade e da composição das diatomáceas presentes no sedimento superficial em relação ao conteúdo de proteínas/carboidratos na Baía de Montevidéu e região costeira adjacente. Foram obtidas amostras sazonalmente durante um ano ao longo de um gradiente de impacto ambiental humano, e as condições tróficas foram determinadas através da análise da composição bioquímica da matéria orgânica do sedimento superficial. A coocorrência de espécies de diatomáceas marinhas-salobras, (Actinocyclus curvatulus, Actinocyclus gallicus, Coscinodiscus excentricus, Coscinodiscus radiatus, Hyalodiscus subtilis, Paralia sulcata) e diatomáceas indicadoras de águas doces (Aulacoseira granulata, Aulacoseira italica, Aulacoseira muzzanensis, Actinocyclus normanii, Amphora copulata, Cyclotella meneghiniana, Nitzschia linearis) sugerem condições mixohalinas estuarinas na área de estudo. As estações amostradas dentro da baía, próximas às fontes contaminadoras, apresentam condições hipertróficas apontadas pelos maiores valores de proteínas e pela alta abundância relativa de Actinocyclus normanii e Cyclotella meneghiniana, sendo que ambas espécies são consideradas cosmopolitas e indicadoras de degradação aquática. As concentrações de proteínas e carboidratos, bem como os pigmentos fotossintéticos registrados na região costeira adjacente sugerem condições meso-eutróficas e uma diluição dos níveis de contaminação do interior da baía rumo à região externa. A análise multivariada entre espécies de diatomáceas e parâmetros ambientais indica que o gradiente trófico possui hierarquicamente maior peso que a salinidade na explicação da distribuição das diatomáceas. Os resultados obtidos demonstram um aperfeiçoamento na habilidade de determinar a contaminação orgânica dentro da área de estudo, já que pela primeira vez tanto as variáveis orgânicas quanto os biopolímeros foram introduzidos como ferramenta para a determinação da relação degradação/saúde de uma das mais populosas regiões do Río de la Plata.

Structure of intertidal and subtidal benthic macrofauna in the northeastern region of Todos os Santos Bay (TSB), northeast Brazil, was investigated during a period of two years. Relationships with environmental parameters were studied through uni-and multivariate statistical analyses, and the main distributional patterns shown to be especially related to sediment type and content of organic fractions (Carbon, Nitrogen, Phosphorus), on both temporal and spatial scales. Polychaete annelids accounted for more than 70% of the total fauna and showed low densities, species richness and diversity, except for the area situated on the reef banks. These banks constitute a peculiar environment in relation to the rest of the region by having coarse sediments poor in organic matter and rich in biodetritic carbonates besides an abundant and diverse fauna. The intertidal region and the shallower area nearer to the oil refinery RLAM, with sediments composed mainly of fine sand, seem to constitute an unstable system with few highly dominant species, such as Armandia polyophthalma and Laeonereis acuta. In the other regions of TSB, where muddy bottoms predominated, densities and diversity were low, especially in the stations near the refinery. Here the lowest values of the biological indicators occurred together with the highest organic compound content. In addition, the nearest sites (stations 4 and 7) were sometimes azoic. The adjacent Caboto, considered as a control area at first, presented low density but intermediate values of species diversity, which indicates a less disturbed environment in relation to the pelitic infralittoral in front of the refinery. The results of the ordination analyses evidenced five homogeneous groups of stations (intertidal; reef banks; pelitic infralittoral; mixed sediments; Caboto) with different specific patterns, a fact which seems to be mainly related to granulometry and chemical sediment characteristics.A estrutura da macrofauna bêntica das regiões entre marés e infralitoral raso na porção nordeste da Baia de Todos os Santos (BTS), nordeste do Brasil, foi investigada durante um período de dois anos. Sua relação com os parâmetros ambientais mensurados foi estudada através de análises estatísticas uni -e multivariadas, sendo os principais padrões de distribuição espacial e temporal relacionados principalmente ao tipo de sedimento e ao conteúdo de três indicadores da matéria orgânica sedimentar (Carbono, Nitrogênio e Fósforo). A macrofauna, composta majoritariamente por anelídeos poliqueta (cerca de 70% do total), apresentou baixa densidade, riqueza de espécies e diversidade, exceto nas estações amostradas nos bancos recifais. Estes se destacam como ambiente peculiar, formado por sedimentos grosseiros, pobres em matéria orgânica e ricos em carbonatos, apresentando fauna abundante e diversificada. A região entre marés e os locais rasos adjacentes à refinaria RLAM são formados por sedimentos compostos principalmente por areia fina e baixo conteúdo orgânico e constituem ambiente instável, com poucas espécies altamente dominantes, como Armandia polyophthalma e Laeonereis acuta. Em outras regiões da BTS, onde dominam os sedimentos pelíticos, densidade e diversidade foram muito baixas, especialmente nas proximidades da refinaria. Aqui, os indicadores biológicos apresentaram seus mais baixos valores, sendo as estações mais próximas (4 e 7) algumas vezes azóicas. A região adjacente de Caboto, inicialmente considerada como controle, apresentou baixa densidade, porém valores médios para diversidade, o que indica ser este ambiente relativamente menos perturbado. Foi possível identificar a existência de 5 grupos com padrões estruturais próprios (entremarés; bancos recifais; infralittoral pelitico; sedimentos mistos; Caboto), que parecem estar relacionados principalmente às características físicas e químicas do sedimento.

Marine Sciences have a very high scientific production worldwide and there are always new research topics, which evidence the continuous progress of these disciplines. In Latin America, Marine Sciences development has had a significant advance in the last 20 years but has not yet achieved the ideal level, and fundamental aspects of some ecosystems and environments in the continent are still unknown. Nowadays, it is very important to promote new challenges in the topic as a way to develop research and management of oceans and their coasts. For this reason, the events conducted along 30 years by the Latin American Association of Researchers in Marine Sciences (ALICMAR-Asociacion Latinoamericana de Investigadores en Ciencias del Mar) show a strong enthusiasm among the scientific community. The Latin American Congress of Marine Sciences (COLACMAR-Congreso Latinoamericano de Ciencias del Mar) is a biannual scientific meeting carried out in different cities of Latin America and the Caribbean uninterruptedly since 1983. These meetings have contributed to encourage research on marine science and related disciplines and to promote sustainable management of aquatic ecosystems.The last edition, the XV COLACMAR “Connecting Marine Sciences in Latin America” was held from 27th to 31th October 2013 in Punta del Este (Uruguay). In this opportunity it was organized by the Faculty of Sciences (University of the Republic-UdelaR) and involved more than 1,000 researchers from 18 countries that presented over a thousand scientific research results. In these five intense days of work and broad discussion scientific results were presented through 16 thematic symposia, which included oral and poster presentations; conferences, seminars, and mini-courses. These activities allowed highlighted important results and recommendations in diverse marine topics developed in universities and management institutions from Latin America and the Caribbean, that was enriched by the relevant contribution of 23 speakers from international cutting-edge research worldwide, who are referents in their subjects.As a result of these intensive days of presentations and discussions, the idea of embodying all these knowledge by publishing the results in a scientific journal arose. This idea is original in the scope of COLACMAR, since it never was done until now, and promoted the search and structuring of a dedicated volume in the

Sorting benthic mactofauna is the slowest and boring stage of ali henthic study. 80, trying to save time, many kind of apparatus have been developed (Lauff et aJ., 1961; Powers & Rohertson, 1965; Worswick & Barhour, 1974; Robinson & Chandler, 1993). Howcver, many of these dcvices are complcx and dirticult to construct (Magdych, 1981). Most of the descrihed designs employs the elutriation technique. It consists in removing the animais from the bottom hy passing a continuous flux of water through the sediment, which puts ali but the heaviest materiais in suspension in the water column. The suspended material is then retained bya collection dcvice. As usual in benthic marine sampling, the sediments are preliminary sieved in the ficld to rcducc their volume. Thc elutriator is employed prior to sorting under stereomicroscope, cleaning the sample and saving time. Usually the described devices for clutriationare designed for small samples, or samples from rivers and places with muddy sediments (Lauff et ai., 1961;Worswick & Barbour, 1974;Magdych, ]981). However, when working with large samples in the continental shelf, sorting is a lengthy process, which dclays very much the analysis of the data. Besides time, sorting is also related withthe type of sediment. On surveys performed in coastal areas, frcquently ali kind ofbottoms are found: from coarse and sandy to fine and muddy, with mixcd types includcd. So, an apparatus that saves time and is effective in alI substrates collected, will be extremely useful to bcnthic researchers. The device described below has proven to be very effeetive in separating the bcnthic macrofauna from a variety of marine coastal sediments, including common coarse botloms.