No abstract

We report new occurrence records of Euterpe edulis Mart. and compare them to a database of known occurrences data available in online repositories. The new records are from an Atlantic Forest fragment in São José do Capinzal village, municipality of Chapecó, Santa Catarina, Brazil. We found 1,393 occurrence records in the online database, of which 491 are unique records primarily from within the Atlantic Forest remnants. We also present photographs, distribution maps, and ecological characterizations that may be useful for future studies.

O objetivo deste estudo foi avaliar a diversidade vegetal de fanerógamas em três matas de galeria no Distrito Federal, Brasil. O estudo foi realizado na Área de Proteção Ambiental Gama-Cabeça de Veado, a partir do levantamento fitossociológico em 12 parcelas paralelas aos córregos das matas de galerias amostradas, totalizando 3600 m2 de área. Foram identificadas 146 espécies, sendo Fabaceae, Myrtaceae e Rubiaceae as famílias mais representativas. Apenas sete espécies ocorreram concomitantemente nas áreas estudadas, indicando elevada diversidade, sobretudo em termos de árvores e arbustos. Os valores de riqueza de espécies e diversidade de Shannon foram maiores no córrego Cabeça-de-Veado (JBB), comparado ao córrego Capetinga (FAL) e Roncador (IBGE), respectivamente. Enquanto que a Dominância Absoluta apresentou maiores valores no córrego Roncador, comparado aos córregos Capetinga e Cabeça-de-Veado, respectivamente. Assim, observamos que a diversidade de espécies está relacionada à heterogeneidade ambiental das matas amostradas, as quais estão relacionadas as características edáficas e do regime hidrológico.

AIM: The objective of this study was to determine the rate of decomposition of two dominant arboreal species (Rhizophora mangle and Avicennia schaueriana) in two Brazilian subtropical mangroves (Ratones and Itacorubi) and their relationship with abiotic factors during two periods of the year (winter and summer). METHODS: Senescent leaves (4 ± 0.1 g dry weight) were placed into litter bags (20 × 25 cm with 1 cm mesh size) and submersed in mangrove forests during a winter and a summer sampling period. Replicates (n = 4) of each detritus sample were obtained from the mangroves after 7, 15, 30, 60, 90 and 120 days of incubation during both time periods. During each period, in situ measurements were taken to obtain the temperature, electrical conductivity, pH, and dissolved oxygen in the water column. RESULTS: The species R. mangle and A. schaueriana exhibited slow rates of decomposition at Itacorubi and intermediate rates at Ratones during the winter, while quick rates were observed at both sites during the summer; this result suggested that water temperature is an influential factor. There was no difference in the loss of mass between the sites during the winter, but in the summer, the highest values were observed for R. mangle in Ratones site. The highest summer temperatures were negatively associated with mass loss, suggesting that the temperature is an influential factor. During the winter, remaining mass was associated negatively with electrical conductivity, possibly because of a greater resource available to decomposing communities, and it was also positively associated with oxygen, revealing a pattern opposite to that observed in the literature. CONCLUSIONS: Our results showed that decomposition accelerated with higher temperatures and that electrical conductivity decelerated with increased dissolved oxygen, confirming the effects of abiotic factors on both detritus decomposition and mangrove functioning.

The mosquito Aedes aegypti L. (Diptera: Culicidae) is a vector of arboviral diseases such as dengue fever. Currently, the main approach to mosquito control is the application of synthetic insecticides, which can lead to negative environmental impacts and insecticide resistance in mosquito populations. As such, there has been increased interest in developing alternative methods for control of vector populations such as utilizing plant compounds that act as larvicides. The aim of this work is to evaluate the effectiveness of Eucalyptus sp. (Myrtaceae) essential oils for control of Ae. aegypti larvae. The essential oils of seven Eucalyptus species and hybrids were extracted by hydrodistillation and analyzed by gas chromatography coupled to mass spectrometry. The essential oils were further diluted in water with acetone (0.40%) at the following concentrations: 100, 50, 25, and 10 lg ml À1 . Mortality trials were conducted in plastic containers with a solution of ultrapure water and 200 ll of diluted oil for a total volume of 50 ml per treatment. The experiments for each Eucalyptus species/hybrid and concentration were performed in triplicate, using a control containing only water and acetone. Twenty larvae were added to each container and mortality was recorded at 1, 2, 4, and 24 h. The Eucalyptus essential oils showed larvicidal activity in most of the evaluated concentrations, mainly at 50 and 100 lg ml À1 . Eucalyptus benthamii Maiden & Cambage and the hybrid Urograndis displayed the highest larvicidal potential (100% at 24 h) in the 100 lg ml À1 treatment. Larval mortality of Ae. aegypti showed a positive correlation with the compounds c-, o-cymol, o-cymene, terpineol, 3-dodecylfuran-2,5-dione, a-pinene, globulol, and ledol. The most abundant compounds identified in the essential oils were 1,8-cineole and a-pinene. These results highlight the potential of using Eucalyptus essential oils for the isolation of natural larvicidal products.

No abstract

Riparian forests play an important role in stream ecosystems, as they support biodiversity, reduce water erosion, and provide litter that fuels aquatic biota. However, they are affected by great array of anthropogenic threats (e.g., fire, logging, and organic pollution), which alter species composition and their physical structure. Although forest recovery after disturbance such as logging can take decades, the legacy of forest clear‐cut logging on key processes in tropical riparian ecosystems is mostly unknown. Here, we investigated how litter inputs (leaves, twigs, and reproductive parts) and storage, key processes for carbon and nutrient recycling and for forest and stream biota, are influenced by riparian vegetation undergoing succession (after 28 years from logging) through the comparison of reference and logged forest sites in the Cerrado biome. Litterfall was overall similar between forest types, but litterfall of twigs was twofold higher at logged than reference sites. Similarly, litter inputs from the bank to the stream (i.e., lateral inputs) and streambed storage were 50–60% higher at logged than reference sites. The higher litterfall observed in logged forests could be related to higher proportion of tree species that are characteristic of primary and secondary successional stages, including fast‐growing and liana species, which often are more productive and common in anthropogenic areas. Our results showed that the legacy impact of clear‐cut logging, even if residual woody vegetation is maintained in riparian buffers, can shift the type, quantity, and seasonality of litter subsidies to tropical streams. This knowledge should be considered within the context of management and conservation of communities and ecosystem processes in the forest‐stream interfaces. Abstract in Portuguese is available with online material.

RESUMO.O objetivo deste trabalho foi avaliar as condições ecológicas da bacia do rio Pandeiros com base em métricas das comunidades de invertebrados bentônicos (coletados por meio de Surber), amostradas em 20 pontos de fevereiro, maio, setembro e novembro de 2008 ao longo de uma bacia e as respectivas características limnológicas de cada local. Para isso foram calculadas, levando em consideração como replicas os quatro períodos amostrais (fevereiro, maio, setembro e novembro de 2008), a porcentagem de Ephemeroptera, Plecoptera e Trichoptera (%EPT), o índice de qualidade de água BMWP-CETEC (Biological Monitoring Working Party) e o Protocolo de avaliação rápida. Um total de 17468 invertebrados foram coletados, distribuídos em 67 taxa. A Classe Insecta apresentou maior número de indivíduos e se distribuiu em 52 famílias. A elevada diversidade de taxa indica uma alta preservação da bacia com potencialidade em atuar como área de referência para avaliar a qualidade de água em outras bacias hidrográficas. Os trechos alto e médio da bacia apresentaram boa qualidade da água e não distinguiu entre si. O trecho mais a jusante da bacia, principalmente perto da foz com o Rio São Francisco, é a região mais urbanizada e com grande atividade agropecuária, apresentando os piores índices de qualidade da água. Ambas as métricas utilizadas baseadas na comunidade de invertebrados bentônicos (%EPT e BMWP-CETEC) e o Protocolo de Avaliação Rápida foram eficazes na avaliação de impactos antrópicos. Assim estes resultados apesar de serem específicos para bacia do rio Pandeiros permitem que suas conclusões gerais possam ser utilizadas para outros locais de região tropical do bioma Cerrado.[Palabras clave: ecologia de rios, EPT, BMWP-CETEC, protocolo de avaliação rápida] ABSTRACT. Environmental assessment of the Pandeiros river using macroinvertebrates as indicators of water quality:The aim of this study was to assess the ecological conditions of the Pandeiros River Watershed using the metrics of benthic macroinvertebrate communities (collected by Surber), sampling at 20 points (including their limnological characteristics) among February, May, September and November 2008 along watershed. We calculated, taking into account the replicas as four sampling periods (February, May, September and November 2008), the percentage of Ephemeroptera, Plecoptera and Trichoptera (% EPT), the index of water quality-CETEC BMWP (Biological Monitoring Working Party) and the Protocol of rapid assessment. A total of 17468 invertebrates were collected, distributed in 67 taxa. The Insecta class had the greatest number of individuals and was distributed in 52 families. The high diversity indicates a higher rate of preservation of the watershed with the potential to act as a reference for assessing the quality of water in other watersheds. The middle and upper stretches of the water had good water quality and did not distinguish between them. The section further down the watershed, particularly near the mouth of the Rio Sao Francisco, is the most urbanized region, ...