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A new species of Moneuptychia Forster (Lepidoptera: Satyrinae, Euptychiina) from the highlands of Southeastern Brazil
Freitas, André V.L.;
Neotropical Entomology , 2007, DOI: 10.1590/S1519-566X2007000600014
Abstract: this paper describes a new species of moneuptychia forster from the summits of the mantiqueira and espinha?o mountain ranges in southeastern brazil, details the morphology of adults and immatures of this species, and discusses the definition of the genus moneuptychia.
Soils associated with rock outcrops in the Brazilian mountain ranges Mantiqueira and Espinha?o
Benites, Vinicius M.;Schaefer, Carlos Ernesto G. R.;Simas, Felipe N. B.;Santos, Humberto G.;
Brazilian Journal of Botany , 2007, DOI: 10.1590/S0100-84042007000400003
Abstract: espinha?o and mantiqueira are two mountain ranges of great importance in brazil. in the uppermost parts of these areas, unique ecosystems occur, generally associated with rock outcrops, they are collectively called high altitude rocky complexes. these environments show distinct soil and biota characteristics in relation to the surrounding biome. the soils are generally shallow, coarse textured, with high al3+ and varying amounts of organic matter. entisols, inceptsols and histosols are dominant, directly associated with the rock outcrops, and forming a complex mosaic of soils. some of these soils are endemic, based on peculiar conditions of parent materials, topography and vegetation, and this pedodiversity is important for detecting unique and endangered soils. in these soils, organic matter is highly humified, with a great amount of soluble forms and conspicuous presence of charcoal. spodic horizons and dark water rivers are typically associated with quartzite and quartzite outcrops, formed by illuviation of organic compounds, being less common in granitic rocks. the very low nutrient content of these soils and other environmental limitations required the development of specific physiological and morphological plant adaptations. most high altitude environments are unstable under current climatic conditions, and anthropic interventions may be accelerating this process. detailed soil surveys are necessary for a better understanding of the role of these soils in ecological processes and for the development of adequate conservation policies.
Insetos indutores de galhas da por??o sul da Cadeia do Espinha?o, Minas Gerais, Brasil
Carneiro, Marco Antonio A.;Borges, Rafael A. X.;Araújo, Ana P. A.;Fernandes, G. Wilson;
Revista Brasileira de Entomologia , 2009, DOI: 10.1590/S0085-56262009000400007
Abstract: galling species richness is higher at intermediate latitudes on warm habitats and sclerophyllous vegetation under water and nutrient stress. in the tropical region, galling species richness is higher in rupestrian fields. here the gall-inducing insects and their host plants of the southern portion of the espinha?o range, southeastern brazil are described. 60 study sites from six distinct regions along the espinha?o range, at minas gerais state were selected. in each study site 100 plants were sampled summing up to 6,000 plants censused along an altitudinal gradient ranging from 668m to 1860m a.s.l. a total of 241 distinct galls morphotypes were found on 142 host plant species belonging to 29 families from a total 384 species censused. the richest galling fauna was found in the asteraceae (42%), mainly the genus baccharis. the largest proportion of galls (85%) was induced by cecidomyiidae followed by lepidoptera (4%) and homoptera (3%). stems were the most frequently galled plant organ (72%) while the most common shapes were elliptical (37%) and globoid (36%). the host plant species presenting the highest number of gall morphotypes types was baccharis pseudomyriocephala with 10 galls. this study supported the assertion that rupestrian fields present the highest galling species richness.
Riffle and pool fish communities in a large stream of southeastern Brazil
Langeani, Francisco;Casatti, Lilian;Gameiro, Helena Seixas;Carmo, André Bellucco do;Rossa-Feres, Denise de Cerqueira;
Neotropical Ichthyology , 2005, DOI: 10.1590/S1679-62252005000200009
Abstract: the structure of the fish communities of a pool and a rapid in the ribeir?o santa bárbara is described. this stream of 5th order is a direct tributary of the rio tietê in the system of the upper rio paraná. thirty three species, from nine families and three orders, were referred in the two mesohabitats: the pool with 31 species, and the rapid with 18. orders characiformes, siluriformes, and perciformes presented the greatest number of species in the two mesohabitats. the families characidae and loricariidae were the most specious, followed by cichlidae in the pool, and by parodontidae in the rapid. most species were accidental, 17 in the pool, and 10 in the rapid, and only six were constant in the two mesohabitats. the greatest diversity and evenness occurred in the pool. the seasonal variation for both assemblages was high, with the pool having a high turnover of species that could be due to the proximity with main channel of the rio tietê.
Stream fish, water and habitat quality in a pasture dominated basin, southeastern Brazil
Casatti, L.;Langeani, F.;Silva, A. M.;Castro, R. M. C.;
Brazilian Journal of Biology , 2006, DOI: 10.1590/S1519-69842006000400012
Abstract: a fish survey in 35 stream reaches (from 1st to 3rd order) with physicochemical and habitat assessment in the s?o josé dos dourados system, southeastern brazil, was conducted. most of the basin land cover (77.4%) is used for pasture. from the sampled stream reaches, 24 were of good physicochemical quality, 10 of fair quality, and only one of poor quality. a habitat assessment showed that 10 stream reaches were considered fair, 22 were poor, and 3 were very poor. fifty species were collected and their abundances showed strong correlation with habitat descriptors. in addition to the correlation between fish abundance and habitat, some species also showed optimal distribution related to the degree of physical habitat conservation. streams located in this region experience organic pollution, but the most important aspect is the decline of the instream physical habitat condition, especially in first order streams, which negatively affects coarse substrates and water column dependent fish species. effluent control, riparian vegetation restoration programs, siltation control and adequate sustainable soil use are practices which could mitigate such impacts.
Seasonal diet shifts of seven fish species in an Atlantic rainforest stream in Southeastern Brazil
Deus, C. P.;Petrere-Junior, M.;
Brazilian Journal of Biology , 2003, DOI: 10.1590/S1519-69842003000400005
Abstract: we analyzed the stomach contents of 116 individuals belonging to seven fishes species in order to investigate seasonal changes in feeding strategy and how trophic interactions between species affect community structure in an atlantic rainforest stream in southeastern brazil. oligosarcus hepsetus and pimelodus sp. consumed fewer items during the winter. phalloceros caudimaculatus switched feeding habits from detritus during summer to algae during winter. these examples are related to variations in food availability and species feeding selectivity. the highest diet overlap values, for most species, as measured using schoener's index, were observed in summer, along with a species tendency to be more generalist. feeding pattern variation may influence the fish community structure.
Seasonal diet shifts of seven fish species in an Atlantic rainforest stream in Southeastern Brazil  [cached]
Deus C. P.,Petrere-Junior M.
Brazilian Journal of Biology , 2003,
Abstract: We analyzed the stomach contents of 116 individuals belonging to seven fishes species in order to investigate seasonal changes in feeding strategy and how trophic interactions between species affect community structure in an Atlantic rainforest stream in Southeastern Brazil. Oligosarcus hepsetus and Pimelodus sp. consumed fewer items during the winter. Phalloceros caudimaculatus switched feeding habits from detritus during summer to algae during winter. These examples are related to variations in food availability and species feeding selectivity. The highest diet overlap values, for most species, as measured using Schoener's index, were observed in summer, along with a species tendency to be more generalist. Feeding pattern variation may influence the fish community structure.
Fish assemblage structure in a first order stream, southeastern Brazil: longitudinal distribution, seasonality, and microhabitat diversity
Casatti, Lilian;
Biota Neotropica , 2005, DOI: 10.1590/S1676-06032005000100009
Abstract: this study was carried out on a first order stream in the morro do diabo state park, southeastern brazil. three equidistant stream stretches - upper, middle, and lower - were chosen for underwater observations and fish collections that were performed in the dry (june and september 2000) and wet seasons (december 2000 and march 2001). of the 18 fish species documented, 11 were considered resident year round. phalloceros caudimaculatus, hypostomus nigromaculatus, hisonotus francirochai, trichomycterus diabolus, and hypostomus ancistroides represented 90% of the collected specimens. the highest richness and abundance occurred during the wet season. in general, the longitudinal addition of species follows the addition of microhabitats. sexually mature individuals were present throughout the year for the majority of the species, which suggests broad reproductive activity. however, given that most juveniles specimens were collected during the wet season, it is hypothesized that reproduction and survival rates must be higher during this season due to higher availability of critical resources, most probably food and shelter.
Ephemeroptera, Plecoptera and Trichoptera assemblages in litter in a mountain stream of the Atlantic Rainforest from Southeastern Brazil
Crisci-Bispo, Vera L.;Bispo, Pitágoras C.;Froehlich, Claudio G.;
Revista Brasileira de Zoologia , 2007, DOI: 10.1590/S0101-81752007000300004
Abstract: the study of ephemeroptera, plecoptera and trichoptera associated with litter in southeastern brazil streams aimed to answer the following questions: 1) does richness and composition of ept fauna differ between riffle and pool mesohabitats despite being associated to the same substratum, litter? 2) does the similarity of the ept fauna between both mesohabitats change with time? 3) does the ept functional feeding structure differ between both mesohabitats (riffles-pools)? in order to answer these questions, monthly collections, from november 1999 to june 2000, were done in ribeir?o (stream) bocaina with a d-net (10 litter patches in riffles and 10 in pools). the ept fauna at ribeir?o bocaina was more diversified and more abundant in the litter in riffles than in the litter in pools, although, when richness was standardized for the same number of individuals it became similar in both conditions. ept fauna was very different between both mesohabitats in terms of faunal composition as well as in terms of function. probably it was due to differences in water speed, in the time of litter residence and in the concentration of dissolved oxygen between both mesohabitats.
Spatial and temporal variability of agricultural pollutants in an agricultural headwater stream within a multipond system,southeastern China
Spatial and temporal variability of agricultural pollutants in an agricultural headwater stream within a multipond system, southeastern China

MAO Zhan-po,YIN Cheng-qing,SHAN Bao-qing,
MAO Zhan-po
,YIN Cheng-qing,SHAN Bao-qing

环境科学学报(英文版) , 2004,
Abstract: The spatial and temporal variability of nutrients and suspended solids were investigated for two years in a 1.8 km agricultural headwater stream, located by Chaohu Lake, southeastern China. The stream form was greatly modified by human activities into channelized, pond and estuary shapes. The stream could be divided into 4 channelized reaches(1.3 km), a pond reach(0.15 km) and 3 estuary reaches(0.36 km). It was found that nutrients and TSS concentrations in the stream showed temporal variability, and higher concentrations occurred in months with high precipitation and intensive agricultural activities. And, retention of total nitrogen(TN), nitrate(NO- 3-N), ammonium(NH 4-N) and total suspended solids(TSS) predominantly occurred in the pond reach and estuary reaches with larger width and low current velocity. Pollutants retained in these reaches accounted for more than 50% of those retained in whole stream. The retention mostly happened in the rain-runoff events and it was 7 to 27 times than that in base flow. The results showed that the channelized reach was the most important source for pollutants release under either runoff or base flow, and its release accounted for more than 90% of whole stream release. There was a high spatial variability of nutrients retention in different channelized reaches. The channelized reach directly discharging into the pond did always retain nutrients and TSS under base flow and runoff conditions, whereas the other channelized reaches performed differently in different hydrological conditions. The high spatial and temporal variability of nutrients and TSS in the stream indicated that anthropogenic disturbance of the agricultural headwater stream, such as channelization and excavation, would be expected to decrease the capacity of nutrients retention in the stream.
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