Interconnected marine habitats form a single continental-scale reef system in South America.

Large gaps in reef distribution may hinder the dispersal of marine organisms, interrupting processes vital to the maintenance of biodiversity. Here we show the presence and location of extensive reef habitats on the continental shelf between the Amazon Reef System (ARS) and the Eastern Brazilian Reef System (ERS), two reef complexes off eastern South America. Formations located 20-50 m deep include both biogenic and geogenic structures. The presence of diverse reef assemblages suggests the widespread occurrence of rocky substrates below 50 m. These habitats represent an expansion of both the ARS and ERS and the closure of the only remaining large-scale gap (~ 1000 km) among West Atlantic reef environments. This indicates that the SW Atlantic harbors a single, yet heterogeneous, reef system that stretches for about 4000 km, and thus, represents one of the largest semi-continuous tropical marine ecosystems in the world.

Functional trade-offs in volume allocation to xylem cell types in 75 species from the Brazilian savanna Cerrado.

BACKGROUND AND AIMS: Xylem is a crucial tissue for plant survival, performing the functions of water transport, mechanical support and storage. Functional trade-offs are a result of the different assemblages of xylem cell types within a certain wood volume. We assessed how the volume allocated to different xylem cell types can be associated with wood functional trade-offs (hydraulics, mechanical and storage) in species from the Cerrado, the Brazilian savanna. We also assessed the xylem anatomical characters linked to wood density across species. METHODS: We analysed cross-sections of branches collected from 75 woody species belonging to 42 angiosperm families from the Cerrado. We estimated the wood volume fraction allocated to different cell types and performed measurements of vessel diameter and wood density. KEY RESULTS: The largest volume of wood is allocated to fibres (0.47), followed by parenchyma (0.33) and vessels (0.20). Wood density is positively correlated to cell wall (fibre and vessel wall), and negatively to the fractions of fibre lumen and gelatinous fibres. We observed a trade-off between hydraulics (vessel diameter) and mechanics (cell wall fraction), and between mechanics and storage (parenchyma fraction). The expected positive functional relationships between hydraulics (vessel diameter) and water and carbohydrate storage (parenchyma and fibre lumen fractions) were not detected, though larger vessels are linked to a larger wood volume allocated to gelatinous fibres. CONCLUSIONS: Woody species from the Cerrado show evidence of functional trade-offs between water transport, mechanical support and storage. Gelatinous fibres might be potentially linked to water storage and release by their positive relationship to increased vessel diameter, thus replacing the functional role of parenchyma and fibre lumen cells. Species can profit from the increased mechanical strength under tension provided by the presence of gelatinous fibres, avoiding expensive investments in high wood density.

Aquaculture facilities promote populational stability throughout seasons and increase medusae size for the invasive jellyfish Cassiopea andromeda.

Cassiopea jellyfish have successfully invaded several marine ecosystems worldwide. We investigated if Cassiopea andromeda grows larger (umbrella size) and if their populations are more stable in shrimp farms than in mangroves in the Brazilian coast. Our results show that jellyfish abundance is higher in the shrimp farm during the rainy season and in the mangrove during dry season. The population is stable during both seasons in the shrimp farm, but unstable in the mangroves, as jellyfish are absent during rainy season. Shrimp farm-associated jellyfish are three times larger than those in the mangroves, regardless of season. We recorded the largest (49.2 cm of umbrella diameter) ever C. andromeda individual in the shrimp farm. Unlike the mangroves, the shrimp farm provides environmental intra-annual stability that promotes jellyfish growth and population persistence. Therefore, C. andromeda populations can be seasonally dynamic and artificial environments such as aquaculture facilities may facilitate the invasion process.

Effects of outdoor cultures on the growth and lipid production of Phaeodactylum tricornutum using closed photobioreactors.

One of the principal challenges for large scale production of microalgae is the high costs of biomass production. Aiming for minimize this problem, microalgal biodiesel production should focus on outdoors cultures, using available solar light and allowing lower energy cost process. Testing species that proved to be common and easy to culture may be a good approach in this process. The present work reports indoor-outdoor cultures of Phaeodactylum tricornutum using different bioreactors types, using cell growth, biochemical composition, and the profiles of the fatty acids produced as the parameters to test the optimization processes. The results show that the use of outdoor cultures is a good choice to obtain P. tricornutum biomass with a good potential for biodiesel production. The microalgae produced reached better growth efficiency, major lipid content and showed an increment in the percentage of saturated fatty acids (required on the biodiesel production) respect indoor cultures. These results are important to show the relevance of using outdoor cultures as a way to improve the efficiency and the energetic balance of the biodiesel production with P. tricornutum algae.

O controle externo sobre a administraçäo pública

Nos últimos anos, importantes medidas legais vêm alterando o cenário político institucional do país, ampliando significativamente a atuaçäo dos orgäos de controle da gestäo dos negócios públicos. O principal objetivo do controle exercido pelas Cortes de Contas é assegurar que a administraçäo das finanças públicas, independentemente da dinâmica políico-social, seja realizada dentro dos parâmetros constitucionais da legalidade, economicidade e moralidade. Os Tribunais de Contas devem estar sempre vigilantes para defender esses postulados, sem perder de vista a necessidade de adaptarem-se às novas realidades, acompanhando a evoluçäo dos acontecimentos