Dieta natural do siri-azul Callinectes sapidus (Decapoda, Portunidae) na regi\ue3o estuarina da Lagoa dos Patos, Rio Grande, Rio Grande do Sul, Brasil

Na região estuarina da Lagoa dos Patos, o siri-azul Callinectes sapidus Rathbun, 1869 é o mais abundante dentre as espécies do gênero. Apesar do siri-azul exercer influência sobre as comunidades bentônicas, por ser considerado um predador do topo da cadeia alimentar, não existem muitos estudos sobre aspectos ecológicos, inclusive sobre a composição e variabilidade sazonal de sua dieta natural, neste estuário. O objetivo principal deste estudo foi investigar a composição da dieta do siri-azul, evidenciando possíveis relações com a comunidade bentônica da região estuarina da Lagoa dos Patos. O período de estudo foi de março de 2003 a março de 2004, com coletas bimestrais. Os organismos foram coletados com auxílio de rede de arrasto de fundo, com malha de 13 mm entre nós opostos. Ainda em campo os animais foram fixados em formol 10%. Após a coleta os animais foram separados quanto ao sexo, medidos (largura e comprimento da carapaça - cm) e pesados (peso - g). Após a triagem, os animais foram dissecados e os intestinos retirados e pesados. As análises dos conteúdos alimentares dos siris demonstraram que os hábitos alimentares são diversificados, constituindo-se principalmente de invertebrados bentônicos. O item encontrado com maior freqüência foi Detrito, seguido pelo molusco filtrador Erodona mactroides Bosc, 1802 (Erodonidae). Crustáceos da classe Ostracoda e grãos de areia foram importantes componentes dos conteúdos dos intestinos anteriores, sendo que areia não foi considerada como item alimentar, propriamente dito. Também foram encontradas cerdas e mandíbulas de poliquetos, além de sementes das macrófitas Ruppia maritima L. (Potamogatonaceae) e Zannichellia palustris L. (Potamogatonaceae). Este estudo serve como subsídio para medidas de proteção e conservação da população do siri-azul, bem como caracteriza relações tróficas com comunidades bentônicas do estuário da Lagoa dos Patos

Seasonal influence of surface and underground continental runoff over a reef system in a tropical marine protected area

11 pages, 8 figures, 2 tablesContinental runoff is an important source of solutes and nutrients to coastal coral reefs. Nevertheless, they can also act as local stressors due to high coastal urbanization and the associated release of untreated effluents. Here we aimed to qualitatively evaluate the effects of seasonality over reefs from the Costa dos Corais Marine Protected Area (Brazil) and to identify the influence of rivers and submarine groundwater discharge (SGD) on the reefs' environmental status. Surface waters from the reef lagoon, local rivers and shoreline porewaters were sampled monthly during a year and abiotic parameters were determined. The results showed that the reef lagoon is oligotrophic throughout most of the year, with conditions that generally favor biological activities, such as calcification. Chlorophyll-a, with an average of 0.78 ± 0.43 mg m−3, was significantly correlated with salinity and radon in excess. This indicates the influence of rivers and SGD over the reefs, especially during the rainy season. These are important sources of nutrients, regulating primary production. However, signs of anthropogenic pressure were found in the local rivers. In addition, porewaters had a N:P ratio (27.68 ± 24.45) which could potentially impact surface waters through SGD by increasing the local trophic status. In summary, the studied reefs still present good water quality conditions, although continental runoff is a significant transport vector of anthropogenic solutes to the areaThis work is part of the Long-Term Ecological Research – Brazil site PELD-CCAL (Projeto Ecológico de Longa Duração - Costa dos Corais Alagoas) funded by the Brazilian National Council for Scientific and Technological Development – CNPq (grant number #441657/2016-8), the Brazilian Coordination for the Improvement of Higher Education Personnel PELD/CAPES (grant number #23038.000452/2017-16) and the Research Support Foundation of the State of Alagoas – FAPEAL (grant number #60030.1564/2016). This paper is also a contribution of the DICAM project, grant CM II #23038.001423/2014-29 (CAPES)Peer reviewe

Growing knowledge: an overview of Seed Plant diversity in Brazil

Abstract An updated inventory of Brazilian seed plants is presented and offers important insights into the country's biodiversity. This work started in 2010, with the publication of the Plants and Fungi Catalogue, and has been updated since by more than 430 specialists working online. Brazil is home to 32,086 native Angiosperms and 23 native Gymnosperms, showing an increase of 3% in its species richness in relation to 2010. The Amazon Rainforest is the richest Brazilian biome for Gymnosperms, while the Atlantic Rainforest is the richest one for Angiosperms. There was a considerable increment in the number of species and endemism rates for biomes, except for the Amazon that showed a decrease of 2.5% of recorded endemics. However, well over half of Brazillian seed plant species (57.4%) is endemic to this territory. The proportion of life-forms varies among different biomes: trees are more expressive in the Amazon and Atlantic Rainforest biomes while herbs predominate in the Pampa, and lianas are more expressive in the Amazon, Atlantic Rainforest, and Pantanal. This compilation serves not only to quantify Brazilian biodiversity, but also to highlight areas where there information is lacking and to provide a framework for the challenge faced in conserving Brazil's unique and diverse flora