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Os impactos ambientais provocados pela piscicultura podem levar a alterações nos ecossistemas aquáticos e principalmente nas comunidades de peixes. Neste artigo buscamos investigar as possíveis alterações provocadas a partir da construção de viveiros em leitos de igarapés amazônicos sobre as cadeias tróficas das comunidades de peixes naturais da Amazônia Central. Os locais de estudos foram nos municípios de Novo Airão e Presidente Figueiredo (Amazonas). Foram realizadas amostragens de captura de peixes (sem piscicultura) nos igarapés com piscicultura e sem piscicultura, segundo a metodologia estabelecida e em pararelo realizamos análises limnológicas. As espécies foram classificadas em categorias tróficas. Realizamos análises comparativas entre riqueza, abundância e biomassa total por igarapé e por local amostrado e posteriormente, realizamos análises de componentes principais (PCA) nas categorias tróficas, a fim de verificar modificações na estrutura das categorias tróficas entre os pontos estudados. Foram coletados 2302 peixes. Os resultados relativos aos parâmetros limnológicos foram similares aos descritos para ambientes aquáticos amazônicos. As categorias tróficas para os locais apresentaram similaridade ao descrito na literatura, com preferência alimentar pelos insetos alóctones. Não foi possível afirmar que mudanças nas categorias tróficas poderiam estar ocorrendo em função da atividade de criação de peixes em canais de igarapés.

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes. Made available in DSpace on 2021-09-03T12:00:26Z (GMT). No. of bitstreams: 1 Program-for-Biodiversity-Research-2021.pdf: 4613827 bytes, checksum: 04b1875a6efdcba448fd73c1ecddf986 (MD5) Previous issue date: 2021

To determine the effect of rivers, environmental conditions, and isolation by distance on the distribution of species in Amazonia. Location: Brazilian Amazonia. Time period: Current. Major taxa studied: Birds, fishes, bats, ants, termites, butterflies, ferns + lycophytes, gingers and palms. We compiled a unique dataset of biotic and abiotic information from 822 plots spread over the Brazilian Amazon. We evaluated the effects of environment, geographic distance and dispersal barriers (rivers) on assemblage composition of animal and plant taxa using multivariate techniques and distance- and raw-data-based regression approaches. Environmental variables (soil/water), geographic distance, and rivers were associated with the distribution of most taxa. The wide and relatively old Amazon River tended to determine differences in community composition for most biological groups. Despite this association, environment and geographic distance were generally more important than rivers in explaining the changes in species composition. The results from multi-taxa comparisons suggest that variation in community composition in Amazonia reflects both dispersal limitation (isolation by distance or by large rivers) and the adaptation of species to local environmental conditions. Larger and older river barriers influenced the distribution of species. However, in general this effect is weaker than the effects of environmental gradients or geographical distance at broad scales in Amazonia, but the relative importance of each of these processes varies among biological groups.

Made available in DSpace on 2018-11-30T03:55:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-19 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Several hypotheses are used to explain species richness patterns. Some of them (e. g. species- area, species-energy, environment-energy, water-energy, terrestrial primary productivity, environmental spatial heterogeneity, and climatic heterogeneity) are known to explain species richness patterns of terrestrial organisms, especially when they are combined. For aquatic organisms, however, it is unclear if these hypotheses can be useful to explain for these purposes. Therefore, we used a selection model approach to assess the predictive capacity of such hypotheses, and to determine which of them (combined or not) would be the most appropriate to explain the fish species distribution in small Brazilian streams. We perform the Akaike's information criteria for models selections and the eigenvector analysis to control the special autocorrelation. The spatial structure was equal to 0.453, Moran's I, and require 11 spatial filters. All models were significant and had adjustments ranging from 0.370 to 0.416 with strong spatial component (ranging from 0.226 to 0.369) and low adjustments for environmental data (ranging from 0.001 to 0.119) We obtained two groups of hypothesis are able to explain the richness pattern (1) water-energy, temporal productivity-heterogeneity (AIC = 4498.800) and (2) water-energy, temporal productivity-heterogeneity and area (AIC = 4500.400). We conclude that the fish richness patterns in small Brazilian streams are better explained by a combination of Water-Energy + Productivity + Temporal Heterogeneity hypotheses and not by just one. Univ Fed Para UFPA, Lab Ictiol Altamira, Altamira, Para, Brazil Univ Estadual Maringa, Nucleo Pesquisas Limnol Ictiol & Aquicultura Nupe, Maringa, Parana, Brazil Univ Estadual Paulista UNESP, Lab Ictiol, Sao Jose Do Rio Preto, SP, Brazil Univ Paulista, Sorocaba, SP, Brazil Univ Estado Rio De Janeiro, Dept Ecol, Rio De Janeiro, RJ, Brazil Univ Fed Ceara, Dept Biol, Ctr Ciencias, Fortaleza, Ceara, Brazil Univ Fed Ceara, Inst Ciencias Mar LABOMAR, Fortaleza, Ceara, Brazil Univ Fed Rio Grande do Norte UFRN, Dept Bot Ecol & Zool, Ctr Biociencias, Natal, RN, Brazil Univ Fed Lavras UFLA, Dept Biol, Lavras, MG, Brazil UFT, Porto Nacl, Tocantins, Brazil Univ Fed Para UFPA, Inst Ciencias Biol, Belem, Para, Brazil INPA, Coordenacao Biodiversidade, Manaus, Amazonas, Brazil Univ Brasilia, Dept Zool, Brasilia, DF, Brazil Univ Fed Sao Carlos, Sorocaba, SP, Brazil Pontificia Univ Catolica Goias, Programa Mestrado Sociedade Tecnol & Meio Ambient, UNIEvangel, Goias Ctr Biol Aquat, Goiania, Go, Brazil UFES, Dept Ciencias Agr & Biol, Ctr Univ Norte Espirito Santo CEUNES, Sao Mateus, ES, Brazil Univ Estadual Paulista, Inst Biociencias, Botucatu, SP, Brazil Univ Fed Minas Gerais, Dept Genet Ecol & Evolucao, Inst Ciencias Biol, Belo Horizonte, MG, Brazil Univ Fed Goias, Dept Ecol, Inst Ciencias Biol, Campus 2 UFG, Goiania, Go, Brazil Univ Estadual Paulista UNESP, Lab Ictiol, Sao Jose Do Rio Preto, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Botucatu, SP, Brazil CNPq: 457463/2012-0 CNPq: 552009/2011-3 CNPq: 471283/2006-1 CNPq: 304002/2014-3 FAPEMIG: 304002/2014-3

There is broad consensus that the diversity of functional traits within species assemblages drives several ecological processes. It is also widely recognized that rare species are the first to become extinct following human-induced disturbances. Surprisingly, however, the functional importance of rare species is still poorly understood, particularly in tropical species-rich assemblages where the majority of species are rare, and the rate of species extinction can be high. Here, we investigated the consequences of local and regional extinctions on the functional structure of species assemblages. We used three extensive datasets (stream fish from the Brazilian Amazon, rainforest trees from French Guiana, and birds from the Australian Wet Tropics) and built an integrative measure of species rarity versuscommonness, combining local abundance, geographical range, andhabitat breadth. Using different scenarios of species loss, we found a disproportionate impact of rare species extinction for the three groups, with significant reductions in levels of functional richness, specialization, and originality of assemblages, which may severely undermine the integrity of ecological processes. The whole breadth of functional abilities within species assemblages, which is disproportionately supported by rare species, is certainly critical in maintaining ecosystems particularly under the ongoing rapid environmental transitions. © 2016 The Author(s) Published by the Royal Society. All rights reserved.

Studies about fish assemblages in Brazilian streams have grown in recent years, however, it remains unclear whether this increase is followed by increments in the diversity of addressed topics and theoretical frameworks adopted by researchers. We performed a systematic search for Brazilian studies on stream fish assemblages recording study region, publication year, objectives, and spatial and temporal scales adopted. The number of studies is unevenly distributed among regions. Most papers describe the general structure of local fish assemblages and their scientific objectives have not varied through time. Studies have been conducted mainly at small temporal and spatial scales, though the latter is increasing over time. We argue for the need of focusing on recently developed ecological theories and frameworks, and expanding the temporal and spatial scales of studies. These changes will improve regional and local conservation policies, and the visibility of aquatic Brazilian research in the global scientific community. © 2016 Associação Brasileira de Ciência Ecológica e Conservação

SUMMARY 1. The effects of seasonal inundation on the biology of fishes on floodplains of large Amazonian rivers are well studied. However, the small seasonal changes in headwater streams are generally considered to have little effect on fish assemblages. 2. In this study, we analysed seasonal changes in the species composition and abundance of fish in small Amazonian forest streams. We sampled fish with hand and seine nets in headwater streams in a 10 000 ha terra-firme forest reserve near Manaus, Brazil. Each stream was surveyed at the end of the 2005 dry season, at the beginning of the 2006 rainy season and at the beginning of the 2006 dry season, by means of a standardized sampling effort. 3. The numbers of individuals and species caught were higher in the dry season, but rarefaction analyses indicated that greater species numbers could have been due simply to the larger number of individuals caught. 4. Between the dry and rainy season, the direction of changes in species composition in multivariate space varied among sites, especially for quantitative (abundance) data. However, the observed variation among sites was the less than expected if the directions of change were random. 5. Fish assemblages in the second dry season were more similar to those in the previous dry season than expected if changes in species composition among seasons were random. This indicates that a general seasonal pattern in fish assemblages can be detected, despite the existence of some erratic site-specific changes. 6. Most of the species that showed large seasonal variations in density occupy temporary ponds during the rainy season, when much of the valley is inundated and pond networks form adjacent to streams. Short-duration lateral migrations to these ponds may play an important role in the seasonal fish-assemblage dynamics in Amazonian headwater streams. 7. Our results contrast with previous studies on small Amazonian streams, which have found little seasonal change in fish assemblages, and highlight the importance of the abundance of common species as an indicator of general fish assemblage structure in biological monitoring programmes.

SUMMARY 1. The effect of habitat structural features and physicochemical characteristics of the water on the composition and richness of fish assemblages in temporary ponds near streams were examined at three spatial scales: among ponds, among streams and between drainage basins, in a ‘terra-firme’ (not subject to long-term flooding) forest reserve in Central Amazonia. 2. The fish assemblage in temporary ponds was composed of subsets of 18 small-bodied species widely distributed in the reserve. The assemblages had a nested subset structure, where smaller ponds contained subgroups of the species found in larger ponds. 3. Species composition and richness in temporary ponds were similar between drainage basins, although the fish assemblages in streams differed between basins. 4. Fish assemblage structure was influenced by local factors related to habitat structure, such as pond area and depth, canopy cover and hydroperiod. Physicochemical characteristics of the water in the ponds were similar between drainage basins and had little detectable effect on the structure of pond fish assemblages. 5. No correspondence was found between the composition, richness or abundance of fishes in the ponds and in stretches of the streams adjacent to the ponds. Therefore, it is not possible to predict the composition of these temporary pond fish assemblages from the fish assemblages found in adjacent streams.

Resemblance to dead leaves is a well known type of camouflage recorded for several small vertebrates that dwell in the leaf and root litter on the ground. We present here instances of such resemblance in three species of nocturnal fishes (Siluriformes and Gymnotiformes) that spend the daytime among submersed root-tangle with leaf litter in Amazonian streams. All three species are very difficult to spot visually, due both to their shape and colors which blend with the substrate, as well as to the heterogeneous nature of their cover. Two species were recorded to lie on their sides, which adds to their resemblance to dead leaves. When disturbed, one species may drift like a waterlogged leaf, whereas another moves upwards the root-tangle, exposing its fore body above the water surface. We regard their leaf-like shapes, cryptic colors, and escape movements as a convergence in defensive responses to visually hunting aquatic vertebrates, most likely diurnal predaceous fishes. Semelhança com folhas mortas é um tipo bem conhecido de camuflagem, presente em diversos pequenos vertebrados que vivem em meio à serapilheira do chão da floresta. Apresentamos aqui exemplos deste tipo de semelhança em três espécies de peixes de hábitos noturnos (Siluriformes e Gymnotiformes) que permanecem durante o dia em meio a aglomerados de raízes e folhas submersas em igarapés amazônicos. As três espécies são difíceis de localizar visualmente, tanto devido ao formato e cores, que se confundem com o substrato, como pela heterogeneidade estrutural dos seus abrigos. Duas espécies foram observadas deitadas de lado durante o dia, o que aumenta sua semelhança com folhas mortas. Quando perturbada, uma das espécies deixa-se levar à deriva como uma folha semi-encharcada, ao passo que outra espécie se desloca para cima, nos aglomerados de raízes, expondo a porção anterior do corpo acima da superfície da água. Consideramos o formato semelhante a uma folha, as cores crípticas e os movimentos de fuga, como uma convergência de respostas defensivas a vertebrados aquáticos que caçam visualmente orientados, provavelmente peixes predadores de hábitos diurnos.

Small streams with acidic, nutrient-poor waters form a dense hydrological system in Central Amazonia. However, little is known about the fish assemblages that occur in these systems. We investigated the relationships among stream size, substrate, and other physical-chemical factors and fish distributions. Fish assemblages and stream characteristics were sampled in 50-m long sections of streams at 38 sites distributed throughout the 100-km2 florestal reserve. Forty-nine species were encountered. The mean richness was similar among sites; however, community composition was correlated with physical and chemical characteristics of the streams. The mean number of species per site (X = 9) was low in relation to the total number of species recorded from the reserve (49) and in relation to the ichthyofauna that has been recorded from small forest streams near the study area. This contrasts with studies in temperate zones where strong patterns of species addition along the river continuum were found, res...

Globally, natural resource management agencies are increasingly recognizing the importance of long-term ecological research (LTER) for monitoring biodiversity, ranging from relatively simple, known, local-level issues, such as managing tourist impacts in a conservation park, to more complex, multifaceted, pervasive, and far-reaching impacts, such as global climate change. Much previous literature has confused protocols for LTER projects to answer current research questions, with developing a system for long-term ecological monitoring. Contrary to perceptions that these LTER systems are not driven by well-defined objectives, we argue that LTER systems can be designed and implemented with the specific objective of providing a basis for both LTER projects and long-term monitoring. We present an overview of RAPELD, an LTER system developed in Brazil, with comparable infrastructure established in Australia and Nepal. The standardized biodiversity infrastructure and research platform provides a long-term basis for powerful multi-disciplinary, multi-scale analyses.

Small headwaters streams of the Neotropical region usually have high species richness and diversity. This study aimed to investigate the species composition and abundance of fish fauna in the headwaters streams of the Madeira-Purus interfluvial plain in the Brazilian Amazon. A total of 22 streams of 1st to 3rd order were sampled during two expeditions at two separate locations in April-May and July of 2007. A total of 5508 fishes were captured using hand and small seine nets, belonging to 78 species, 22 families and six orders. Characiformes was the most diverse taxonomic group in the samples, followed by Gymnotiformes and Siluriformes. Our findings indicate that the fish fauna of streams in the Madeira- Purus interfluvial plain is both rich and diverse and should be considered during the implementation of strengthened environmental conservation strategies in this region. © 2011 Check List and Authors.

Diet and feeding activity of Leporinus amblyrhynchus before, during and after the damming of the rio Corumbá (Goiás State March 1996 to February 1998) were investigated. The diet, evaluated using the Feeding Index (IAi), showed that this species presents an invertivore feeding habit, preying on basically Chironomidae larvae. The feeding activity, estimated using the quantity of food in the stomach during a 24-hour cycle, showed that the feeding occurs mainly in the daytime. Considering the feeding aspects of this species during the formation of the reservatório of Corumbá there were small variations in the parameters (diet and feeding activity) dealt in this study. Neste estudo, foram avaliadas a dieta e atividade alimentar diária de Leporinus amblyrhynchus, antes, durante e após o represamento do rio Corumbá, GO (março 1996 a fevereiro 1998). A dieta, avaliada pelo Índice Alimentar (IAi) mostrou que esta espécie apresenta hábito alimentar invertívoro, consumindo basicamente larvas de Chironomidae. A atividade alimentar diária, estimada pela quantidade de alimento nos estômagos, evidenciou tratar-se de uma espécie basicamente diurna que forrageia preferencialmente nos períodos de maior intensidade luminosa. Tanto a alimentação quanto o comportamento na tomada do alimento aparentemente não foram afetados pelo impacto causado pelo represamento do rio Corumbá.