In this study, we compare orchid bee communities surveyed in four forest remnants of the Atlantic Forest and four reforested areas characterized by seasonal semi-deciduous forest vegetation in different successional stages (mature and secondary vegetation), located in southern Brazil. The sizes of forest remnants and reforested areas varied from 32.1 to 583.9 ha and from 11.3 to 33.3 ha, respectively. All reforested areas were located near one forest remnant. During samplings, totaling nine per study area, euglossine males were attracted to eight scent baits and captured with bait trap and entomological nets. Each forest remnant and its respective reforested area were sampled simultaneously by two collectors. We collected 435 males belonging to nine species of orchid bees distributed in four genera. The number of individuals and species did not differ significantly between different areas, except for a reforested area (size 33.3 ha), which was located far from its respective forest remnant. Our findings also revealed an apparent association between an orchid bee species (Euglossa annectans Dressler 1982) and the most preserved area surveyed in our study, suggesting that this bee is a potential indicator of good habitat quality in recuperating or preserved areas. Our results suggest that reforested habitats located near forest remnants have a higher probability of having reinstated their euglossine communities.

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ABSTRACT. Based on the hypothesis that diel vertical migration (DVM) is a mechanism of predator avoidance, the objective of the present study was to test for the occurrence of DVM in planktivorous fish larvae of Hypophthalmus edentatus (Spix, 1829) (Siluriformes, Pimelodidae) and Plagioscion squamosissimus (Heckel, 1840) (Perciformes, Sciaenidae), and zooplankton (rotifers, cladocerans and copepods) in an isolated tropical lagoon in the floodplain of the Upper Paraná River, Brazil (region of Parque Nacional de Ilha Grande). We investigated spatial overlap between predators (planktivorous fish larvae) and prey (zooplankton), and tested which physical and chemical variables of the water are related to the DVM of the studied communities. We performed nocturnal (8:00 pm and 4:00 am) and diurnal sampling (8:00 am and 4:00 pm) in the limnetic region of the lagoon for six consecutive months, from October 2010 to March 2011, which comprises the reproductive period of the fish species analyzed. During the day the larvae tried to remain aggregated in the bottom of the lagoon, whereas at night they tried to disperse in the water column. Especially for cladocerans, the diel vertical migration is an important behavior to avoid predation larvae of H. edentatus and P. squamosissimus once decreased spatial overlap between secured and its potential predators, which corroborates the hypothesis that DVM is a mechanism of predator avoidance. Although significant correlations were observed between the abiotic factors and WMD of microcrustaceans at certain times of day, the effect of predation of fish larvae on zooplankton showed more important in this environment, because the small depth and isolation not allow great variation of abiotic factors seasonally and between strata the lagoon. KEYWORDS.Vertical distribution, spatial overlap, predator-prey interactions, rotifers, microcrustaceans. RESUMO. Migração vertical diária de predadores (larvas de peixes planctívoras) e presas (zooplâncton) em uma lagoa tropical.Com base na hipótese de que a migração vertical diária (MVD) é um mecanismo que visa evitar predadores, o objetivo do presente estudo foi verificar a ocorrência de MVD em larvas de peixes planctívoras de Hypophthalmus edentatus (Spix, 1829) (Siluriformes, Pimelodidae) e Plagioscion squamosissimus (Heckel, 1840) (Perciformes, Sciaenidae), e nos grupos zooplanctônicos (rotíferos, cladóceros e copépodes) em uma lagoa tropical isolada da planície de inundação do alto rio Paraná, Brasil (região do Parque Nacional de Ilha Grande). Foi investigada a sobreposição espacial entre predadores (larvas de peixes) e presas (zooplâncton), bem como verificar quais variáveis físicas e químicas da água estariam relacionadas com a MVD das comunidades envolvidas neste estudo. Foram realizadas amostragens noturnas (20:00 e 4:00) e amostragens diurnas (8:00 e 16:00) na região limnética da lagoa durante um período de seis meses consecutivos, entre outubro de 2010 a março de 2011, que compreende o período reprodutivo das espécies de peixes analisadas...

Due to intense agricultural and industrial activities, the environment has been affected by increasing amounts of pollutants, such as lead, a toxic heavy metal. When introduced to the environment, toxic metals are distributed and incorporated into the liquid medium, sediments, and aquatic biota; bioaccumulating. This research aimed to identify and quantify the levels of toxic metals present in the waters and sediments of Toledo River, compare the obtained results with legislation and other studies, as well as to evaluate the possible pollutant sources of the water body. Six water and sediment samples were taken at seven strategic sites. The concentrations of Cu, Zn, Fe, Mn, Cd, Pb, and Cr in water were compared to the maximum limits established by Brazilian legislation IN CONAMA No. 357/05, for class II fresh waters. The sediment samples were submitted to nitroperchloric digestion, and then the total concentrations of the metals were determined by flame atomic absorption spectrometry (FAAS). The toxicological quality of the Toledo River has been considerably affected by the activities carried out in its surroundings, such as extensive areas of agriculture, pig farming and industrial areas, causing concentrations of Cd, Fe, and mainly Pb, which is observed at concentrations higher than value allowed by the legislation.

A preocupação mundial com a conservação dos recursos hídricos é causa de conflitos, sendo a escassez de água potável provocada pelas mudanças climáticas e principalmente por ações antrópicas. O objeto de estudo deste projeto é o Rio do Ouro, localizado na cidade de Ouro Verde do Oeste, distante 560 km da capital do estado, Curitiba. Os pontos de coleta são acompanhados pela urbanização com áreas de atividades agrícolas, suinocultura e piscicultura. Localizado entre os municípios de Toledo e Ouro Verde do Oeste no estado do Paraná, sua extensão em linha reta é de 22 km. O objetivo do presente trabalho é avaliar a qualidade da água do Rio do Ouro por meio de avaliação das condições toxicológicas. Este estudo trará contribuições importantes para a elaboração e implantação de práticas de conservação e gestão ambiental, além de servir como base de dados para estudos posteriores sobre o Rio do Ouro. Os teores médios dos metais obtidos durante o período de amostragem indicam baixo impacto ambiental, considerando as atividades agroindustriais e atividade urbana presentes, porém, cabe salientar que estas atividades poderão causar maiores impactos ao referido curso hídrico futuramente, caso o manejo conservacionista das áreas marginais seja abandonado.Palavras-chave: Recursos hídricos. Avaliação toxicológica. Poluição. Paraná. IntroduçãoCerca de 97,5% da água de nosso planeta está presente nos oceanos e mares, na forma de água salgada, ou seja, imprópria para o consumo humano. Dos 2,5% restantes, que perfazem o total de água doce existente, 2/3 estão armazenados nas geleiras e calotas polares. Apenas aproximadamente 0,77% de toda a água está disponível para o nosso consumo, sendo encontrada na forma de rios, lagos, água subterrânea, incluindo ainda a água presente no solo, atmosfera (umidade) e na biota.