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Macroecology is the study of the mechanisms underlying general patterns of ecology across scales. Research in microbial ecology and macroecology have long been detached. Here, we argue that it is time to bridge the gap, as they share a common currency of species and individuals, and a common goal of understanding the causes and consequences of changes in biodiversity. Microbial ecology and macroecology will mutually benefit from a unified research agenda and shared datasets that span the entirety of the biodiversity of life and the geographic expanse of the Earth.

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We investigated spatial and seasonal variation of fish assemblages of Caño Maraca, a creek in Venezuela's Western Llanos, a region with strong wet-dry seasonality. Fishes were surveyed over a 19-year period at three sites along the longitudinal gradient: a headwater site with a narrow channel, a middle site with shallow channels traversing a seasonal wetland, and a lower site where the channel has higher banks. Assemblage composition and presence of species with juveniles and various life history strategies were compared during wet and dry seasons. Overall, fish species richness was lowest at the headwater site and highest at the downstream site. During the wet season, however, species richness is greatest at the middle site, a pattern associated with migration into the site for reproduction and use of the wetland as a nursery. During the dry season, species richness is greater at the downstream site where habitat quality is sufficient to provide suitable habitat for many species. Fish movements and population dynamics in Caño Maraca respond to seasonal environmental changes, and the fish metacommunity appears influenced by species sorting (habitat selection), mass effects (source-sink dynamics), patch dynamics (interspecific differences in colonization and species interaction) as well as random factors (dry-season strandings).(AU)

Investigamos la variación espacial y temporal de los ensambles de peces en el Caño Maraca, un arroyo localizado en los Llanos Occidentales de Venezuela, región caracterizada por una fuerte estacionalidad húmedo-seco. La ictiofauna fue evaluada en intervalos durante un período de 19 años, en tres sitios a lo largo del gradiente fluvial longitudinal: El primer sitio en la cabecera con un canal estrecho e hidrología estable, el segundo, intermedio con canales poco profundos atravesando un humedal estacional y el ultimo en la zona baja donde el canal tiene bancos más altos. La composición del ensamblaje y la presencia de especies con juveniles y diversas estrategias de historia de vida fueron comparadas durante las estaciones húmedas y secas. En general, la riqueza de especies de peces fue menor en el sitio de la cabecera y más alta en el sitio aguas abajo. Sin embargo, durante la época húmeda, la riqueza de especies fue mayor en el sitio central, patrón asociado con la reproducción de peces y el uso del humedal como criadero. Durante la época seca, la riqueza de especies fue mayor en la zona baja donde la calidad del hábitat es suficiente para proporcionar un hábitat adecuado para muchas especies. El movimiento de los peces y la dinámica poblacional en Caño Maraca están relacionadas a cambios ambientales estacionales. Adicionalmente la metacomunidad de peces parece estar influenciada por el ordenamiento de especies (selección de hábitat), efectos de masas (dinámica fuente-sumidero), dinámica de parches (involucrando diferencias interespecíficas en la tasa de colonización y capacidad competitiva) y factores aleatorios (relacionados con la duración de la estación seca).(AU)

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Objetivo: Caracterizar a série histórica do número de municípios infestados por Aedes aegypti e por Aedes albopictus no estado de São Paulo (ESP), de 1986 a 2015. Analisar sua sazonalidade, temperaturas médias, indicadores de infestação de cada espécie, e verificar sua interdependência espacial na Região Metropolitana do Vale do Paraíba Paulista (RMVP). Material e Métodos: Os dados das ações de vigilância entomológica foram obtidos com o índice de Breteau (IB), do banco de dados da Superintendência de Controle de Endemias (Sucen). Foram calculadas as médias aritméticas por mês e ano, e analisadas pelo teste de Wilcoxon. Os mapas de temperatura foram obtidos junto ao Instituto Nacional de Meteorologia (INMET). Para análise geoespacial das espécies na RMVP foi empregado o indicador global de Moran (I) e o estimador de densidade Kernel (k). Resultados: O estado de São Paulo apresentou-se quase que totalmente infestado pelas duas espécies, com registro de coexistência em 93,64% dos municípios. A trajetória geográfica dessas espécies vetoras apresentou-se antagônica, com a sobreposição prevalecendo com o tempo, e sempre com diferenças na abundância larval. A sazonalidade evidenciou o primeiro trimestre de cada ano como o período mais favorável. O aumento das temperaturas médias foi coincidente com a expansão geográfica e temporal de Ae. aegypti. No ESP, a estimativa de densidade larvária de Ae. aegypti foi 4,27 vezes maior do que a observada para Ae. albopictus. Para a RMVP, verificou-se declínio da espécie precursora, Ae. albopictus, após o estabelecimento do Ae. aegypti. O índice global de Moran (I) não revelou dependência espacial entre os municípios analisados. A intensidade da 7 infestação pelo Kernel indicou distribuição heterogênea com áreas críticas para as duas espécies. Conclusão: Ae. aegypti e Ae. albopictus apresentaram, inicialmente, ocupação de áreas geográficas distintas e opostas, porém com o decorrer do tempo observou-se variação no padrão de infestação e coexistência das espécies, onde Ae. aegypti foi a espécie predominante, o que sugere sua superioridade competitiva no ESP. Ambos os vetores mostraram comportamento nitidamente sazonal, com maiores abundâncias nos meses mais quentes. A elevação das temperaturas médias e a expansão da ocorrência de Ae. aegypti foram coincidentes, demonstrando sua contribuição na dispersão desta espécie. A ausência de autocorrelação da infestação dos municípios da RMVP mostrou independência espacial sendo, portanto, dependente de suas características locais. O estimador de densidade de Kernel apontou conglomerados de municípios estratégicos para redução de densidade populacional do vetor. (AU)

Objective: To characterize the historical series of the number of cities infected by Aedes aegypti and by Aedes albopictus in the state of São Paulo (ESP), from 1986 to 2015. To analyze their seasonality, average temperatures, infestation indicators of each species, and to verify their spatial interdependence in Metropolitan Region of the Vale do Paraíba Paulista (RMVP). Material and Methods: The data from entomological surveillance actions were obtained using the Breteau index (IB), from the database of the superintendence of Control of Endemics (Sucen). The arithmetic means were calculated by month and year and, then, analyzed by the Wilcoxon test. The temperature maps were obtained at the National Institute of Meteorology (NIMET). For the geospatial analysis of the species in the Metropolitan Region of the Paraiba Valley (RMVP), Moran global indicator (I) and Kernel density estimator (K) were used. Results: The state of São Paulo demonstrated to be almost totally infected by these two species, with record of coexistence in 93,64% of the cities. The geographic track of these vectors species was antagonistic, but the overlap prevailed over time, and always with differences in larval abundance. The seasonality highlighted the first quarter of every year as the most favorable time. The elevation of average temperatures and the expansion of the occurrence of Ae. aegypti were coincident, demonstrating their contribution in the dispersion of this species. In the ESP, the estimate of Ae. aegypti larval density was 4.27 times higher than that observed for Ae. albopictus. For the RMVP, it could be verified the decline of the precursor species, Ae. albopictus, after the establishing of the Ae. aegypti. The Moran global index (I) did not reveal the spatial dependency 9 among the analyzed cities. The infestation intensity by Kernel indicated a heterogenic distribution with critical areas for both species. Conclusion: Ae. aegypti and Ae. albopictus presented, initially, occupancy in distinct and opposite geographic areas, but with the passage of time it was observed variation in the pattern of infestation and coexistence of the species, where Ae. aegypti was the predominant species, which suggests its competitive superiority in ESP. Both vectors showed distinctly seasonal behavior, with higher abundances in the warmer months. The elevation of average temperatures and the expansion of the Ae. aegypti occurrence, showed its contribution in the dispersion of this species. The absence of the infestation autocorrelation in the cities of the Metropolitan Region of the Paraiba Valley showed spatial independency, being, therefore, dependant of its local characteristics. The Kernel density estimator pointed conglomerates of strategic cities for the reduction of the vector population density. (AU)

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Relationship between diet and morphology of cichlid were analyzed considering that the trophic apparatus determines differential food use among species. Cichlasoma dimerus and Satanoperca pappaterra showed a generalist diet, while Chaetobranchopsis australis and Crenicichla vittata consumed zooplankton and fish, respectively. Significant correlation between morphology and diet was not found, but C. australis differed from the others species in the upper mouth and longer gill rakers. The morphology data and food size segregated the cichlids into three groups. The first was comprised by C. australis, which has many and longer gill rakers and a more protractile mouth, the second by C. vittata, which have a larger and more-protruded mouth and the third by S. pappaterra and C. dimerus, with a smaller and lower mouth. The latter two groups have more widely spaced gill rakers and consumed larger food. Overall, our results showed different patterns of species grouping when considering morphological or diet data. However, to C. australis the gill rakers determine both the type and size of food.(AU)

A relação entre dieta e morfologia de ciclídeos foi analisada considerando que o aparato trófico determina o uso diferencial dos recursos alimentares entre as espécies. Cichlasoma dimerus e Satanoperca pappaterra, apresentaram dieta generalista, enquanto Chaetobranchopsis australis e Crenicichla vittata, consumiram zooplâncton e peixes, respectivamente. Nenhuma correlação significativa foi encontrada entre a morfologia e a dieta, entretanto, C. australis se distanciou das demais espécies, por apresentar boca superior e rastros branquiais longos e numerosos. Os dados de morfologia e tamanho do alimento consumido segregaram os ciclídeos em três grupos. O primeiro foi composto por C. australis , que possui rastros branquiais longos e numerosos, além de maior protractibilidade da boca, o segundo por C. vittata , que tem maior amplitude e protrusão da boca e o terceiro por S. pappaterra e C. dimerus que possuem boca pequena e inferior. Os dois últimos grupos apresentaram ainda, maior distância entre os rastros e consumiram alimentos maiores. Nossos resultados mostraram que, quando somente os dados morfológicos são considerados, as espécies foram agrupadas de forma diferente do que quando apenas os dados de dieta foram considerados. Entretanto, para C. australis os rastros branquiais determinam o tipo e tamanho do alimento.(AU)

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Urban forests are now recognized as essential components of sustainable cities, but there remains uncertainty concerning how to stratify and classify urban landscapes into units of ecological significance at spatial scales appropriate for management. Ecosystem classification is an approach that entails quantifying the social and ecological processes that shape ecosystem conditions into logical and relatively homogeneous management units, making the potential for ecosystem-based decision support available to urban planners. The purpose of this study is to develop and propose a framework for urban forest ecosystem classification (UFEC). The multifactor framework integrates 12 ecosystem components that characterize the biophysical landscape, built environment, and human population. This framework is then applied at the neighbourhood scale in Toronto, Canada, using hierarchical cluster analysis. The analysis used 27 spatially-explicit variables to quantify the ecosystem components in Toronto. Twelve ecosystem classes were identified in this UFEC application. Across the ecosystem classes, tree canopy cover was positively related to economic wealth, especially income. However, education levels and homeownership were occasionally inconsistent with the expected positive relationship with canopy cover. Open green space and stocking had variable relationships with economic wealth and were more closely related to population density, building intensity, and land use. The UFEC can provide ecosystem-based information for greening initiatives, tree planting, and the maintenance of the existing canopy. Moreover, its use has the potential to inform the prioritization of limited municipal resources according to ecological conditions and to concerns of social equity in the access to nature and distribution of ecosystem service supply.

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RESUMO: Renealmia L.f. é um gênero de Zingiberaceae com inúmeros usos, entre eles: ornamental, medicinal e alimentício. Visando ressaltar a importância deste gênero como potencial fonte de recursos agroeconômicos apresenta-se esta revisão sobre aspectos botânicos, ecológicos, farmacológicos, e agronômicos. De um universo de 87 espécies formalmente inseridas em Renealmia, registrou-se indicação de uso popular para 18 destas. Em sua maior parte as indicações de uso estiveram associadas a R. alpinia, R. exaltata e R. guianensis englobando, principalmente, os usos ornamental, alimentício e medicinal. Dentre as 14 espécies com indicação de uso popular medicinal, registram-se pesquisas farmacológicas para apenas quatro: R. alpinia, R. exaltata, R. nicolaioides e R. thyrsoidea. Entretanto, estas pesquisas evidenciam um amplo espectro de bioatividade, com ênfase na ação anticancerígena e antiofídica, especialmente de R. alpinia. Apenas seis espécies foram avaliadas quanto a composição química (R. floribunda, R. guianensis, R. alpinia, R. chrysotricha, R. exaltata e R. nicolaioides), identificando-se perfil químico que corrobora a potencialidade anticancerígena e antiofídica para os representantes deste gênero. Evidenciou-se grande lacuna no que se refere ao conhecimento científico ou técnico para o cultivo de espécies de Renealmia. Isto pode se configurar num impedimento importante na utilização destas espécies como recurso econômico.

ABSTRACT: The Renealmia L.f. is a genus that belongs to the Zingiberaceae with several applications, including the ornamental, medicinal and food ones. Aiming to emphasize the importance of this genus as a potential agro-economic resource, a review of its botanical, pharmacological and agronomic aspects is presented. From 87 species formally inserted in the Renealmia, 20 were registered with popular uses. In general, these popular uses were associated with R. alpinia, R. exaltata and R. guianensis, mainly including the ornamental, nourishing and medicinal uses. Among 14 species with indication of popular medicinal use, pharmacological studies were registered for only four: R. alpinia, R. exaltata, R. nicolaioides and R. Thyrsoidea. However, these studies show a large bioactivity range, with emphasis in the anti-carcinogenic and antiophidic action, especially for R. alpinia. Only six species were analyzed in terms of chemical composition (R. floribunda, R. guianensis, R. alpinia, R. chrysotricha, R. exaltata and R. nicolaioides). Their chemical profiles corroborate the anti-carcinogenic potential for the representatives of this genus. There is a great scientific or technical gap on the cultivation of Renealmia species. This can be an important limiting factor in the use of these species as economical resource.

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Esta artículo, derivado de las discusiones fruto de varias investigaciones realizadas,tiene como objetivo proponer una acción de ruptura respecto a la dinámicadevastadora de la humanidad ante los recursos ambientales y ecosistemas, para lo cual se propone la generación de “incertidumbres semilla” que actúan a modo de acciones pedagógicas de cambio instauradas desde la infancia como registros de acción, retroacción e interretroacción pedagógica-social. Para ello se plantea que la responsabilidad medioambiental y la reconciliación de la humanidad con los ecosistemas, emergen como constructos dialógicos de sentido ecologizante, por lo que deben ser apuntalados en el proceso educativo y (de)construidos en quienes alteran la organización de los sistemas vivos.

This article, derived from the product of several investigations carried out discussions, aims to propose an action of rupture on the devastating dynamics of humanity to environmental resources and ecosystems, which proposes the generation of “uncertainty seeds” that act as a pedagogical actions of change, installed from childhood as records of pedagogical and social action, feedback and inter-feedback. This raises the environmental liability and the reconciliation of humanity with theecosystems, to emerge as dialogic constructs of greening sense, so that it must be underpinned in the educational process and (de) built on those who disrupt the organization of living systems.

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The EC Water Framework Directive (WFD) clearly states that undisturbed reference states of aquatic ecosystems should be used to set standards for restoration. Across Europe defining biological reference status and setting boundaries for ecological status classes continues to represent a major challenge. In the present study we investigate if a paradigm exists among experts that can guide the development of assessment systems based on the normative definitions of ecological status classes of the WFD. Our main questions were: 1) Will experts from species abundance data and typology descriptors independently arrive at similar assessments of ecological status, and 2) Can the expert interpretation of ecological status be transferred into a statistical model allowing for a standardization of assessments from plant assemblages in lowland streams? We used a large dataset covering 1244 randomly distributed stream sites in Denmark and asked a group of experts to independently classify the sites using the WFD's normative definitions of ecological status. According to the combined expert group, no Danish stream sites belonged to the undisturbed reference state. For the remaining ecological status classes we found good concordance in the classification made by the five experts. From this we infer that a common paradigm does exist, which may guide the development of assessment methods for aquatic plants in lowland streams. We also found that the common view of the experts could be transferred into a supervised classification model that can serve as a classification tool for aquatic plant assemblages in lowland streams. We conclude that the combined use of experts and advanced multivariate statistics can provide a useful approach in the development of systems for assessment of ecological status in water types, where a reference network cannot be established.

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Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae) in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase (COI) I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n=179) is presented for the first time in 60 years.

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Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae) in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase ( COI ) I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n = 179) is presented for the first time in 60 years.

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Este artículo de investigación pretende brindar elementos de análisis sobre el complejo tema de la colonización de la naturaleza. En él se hace una argumentación descriptiva basada hallazgos teóricos sobre las relaciones entre el extractivismo, una práctica propia del dispositivo colonial, y lo que aquí denominamos colonización de la naturaleza. El artículo presenta inicialmente un balance del impacto en la configuración de la visión-apropiación ancestral del territorio y su contenido cultural, a raíz de la imposición de una nueva semántica, en referencia al dispositivo de poder colonial. Luego, se analiza la relación del extractivismo con el proceso de colonización de la naturaleza, para finalmente esbozar una reflexión breve vinculando contextos y problemas contemporáneos.

This research paper aims at providing some elements of analysis on the complex issue of the colonization of nature. In it a descriptive argument is carried out based on theoretical findings on the relationships between extractivism, which is a proper practice of the colonial device, and what is here called colonization of nature. The article initially presents an assessment of the impact on the configuration of the ancestral vision and appropriation of the territory and its cultural contents, as a result of the imposition of a new semantics, in reference to the device of the colonial powers. Then, the relationship between extractivism and the process of colonization of nature is analyzed; to finally sketch a brief reflection, by linking contemporary issues and contexts.

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Ecological regionalizations define geographic regions exhibiting relative homogeneity in ecological (i.e., environmental and biotic) characteristics. Multivariate clustering methods have been used to define ecological regions based on subjectively chosen environmental variables. We developed and tested three procedures for defining ecological regions based on spatial modeling of a multivariate target pattern that is represented by compositional dissimilarities between locations (e.g., taxonomic dissimilarities). The procedures use a "training dataset" representing the target pattern and models this as a function of environmental variables. The model is then extrapolated to the entire domain of interest. Environmental data for our analysis were drawn from a 400 m grid covering all of Switzerland and consisted of 12 variables describing climate, topography and lithology. Our target patterns comprised land cover composition of each grid cell that was derived from interpretation of aerial photographs. For Regionalization 1 we used conventional cluster analysis of the environmental variables to define 60 hierarchically organized levels comprising from 5 to 300 regions. Regionalization 1 provided a base-case for comparison with the model-based regionalizations. Regionalization 2, 3 and 4 also comprised 60 hierarchically organized levels and were derived by modeling land cover composition for 4000 randomly selected "training" cells. Regionalization 2 was based on cluster analysis of environmental variables that were transformed based on a Generalized Dissimilarity Model (GDM). Regionalization 3 and 4 were defined by clustering the training cells based on their land cover composition followed by predictive modeling of the distribution of the land cover clusters using Classification and Regression Tree (CART) and Random Forest (RF) models. Independent test data (i.e. not used to train the models) were used to test the discrimination of land cover composition at all hierarchical levels of the regionalizations using the classification strength (CS) statistic. CS for all the model-based regionalizations was significantly higher than for Regionalization 1. Regionalization 3 and 4 performed significantly better than Regionalization 2 at finer hierarchical levels (many regions) and Regionalization 4 performed significantly better than Regionalization 3 for coarse levels of detail (few regions). Compositional modeling can significantly increase the performance of numerically defined ecological regionalizations. CART and RF-based models appear to produce stronger regionalizations because discriminating variables are able to change at each hierarchic level.

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Wetland landscape ecological classification, as a basis for the studies of wetland landscape ecology, directly affects the precision and effectiveness of wetland-related research. Based on the history, current status, and latest progress in the studies on the theories, indicators, and methods of wetland landscape classification, some scientific wetland classification systems, e.g., NWI, Ramsar, and HGM, were introduced and discussed in this paper. It was suggested that a comprehensive classification method based on HGM and on the integral consideration of wetlands spatial structure, ecological function, ecological process, topography, soil, vegetation, hydrology, and human disturbance intensity should be the major future direction in this research field. Furthermore, the integration of 3S technologies, quantitative mathematics, landscape modeling, knowledge engineering, and artificial intelligence to enhance the automatization and precision of wetland landscape ecological classification would be the key issues and difficult topics in the studies of wetland landscape ecological classification.

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The ecological security index (ESI) system including 27 indices for Heilongjiang Province was built up with the pressure-state-response (P-S-R) model. The weights of the indices were determined by analytical hierarchy process (AHP) and the ecological security status classification was evaluated by the ESI model for the years of 2000-2005. Then the development trend of ecological security from 2006 to 2010 was forecasted with the grey dynamic model. The results showed that the ecological security ranked the V grade in 2000 and the III grade in 2005, indicating the increase of ecological security. The forecasting results show that the ecological security will be the III grade for 2006, the II grade for 2007-2009, and the I grade for 2010 (ideal security). Thus it can be seen that the ecological security is ascending year by year, and the ecological environment quality is obviously improved with the implementation of eco-province construction since 2000. Through the effective facilitation of eco-province construction etc., the sustainable and healthy development of ecological security will be finally realized in Heilongjiang Province.

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Two approaches for setting ecological class boundaries, response curves and a simplified mathematical boundary-setting protocol, were tested for coastal, transitional and open waters in the Gulf of Riga, Baltic Sea. The simplified mathematical boundary-setting protocol defines acceptable ecological status based on expert judgment by a uniform relative deviation from reference conditions. In contrast, response curves derive class boundary definitions from observed changes in biological quality elements along environmental pressure gradients for class boundary definitions. Identification of relevant environmental pressures for the construction of response curves was based on a conceptual model of eutrophication in the Gulf of Riga. Response curves were successfully established for summer chlorophyll a and transparency, as well as for macrozoobenthos abundance in the Central Gulf, macrozoobenthos biotic coefficient in the Southern Gulf, and maximum depth of phytobenthos in the Northern Gulf. In the Gulf of Riga response curves almost always permitted a larger deviation from reference conditions than the 50% deviation applied for the simplified mathematical boundary-setting protocol. The case study clearly demonstrated that class boundary definitions should take into account the sensitivity of the target water body. Also, the class boundaries for different ecological quality elements were internally more consistent than those derived by the simplified mathematical boundary-setting protocol.

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A ictiofauna de quatro trechos da bacia hidrográfica do rio Tibagi foi amostrada mensalmente de maio de 2001 a abril de 2002, com redes de espera (totalizando 1.000 m²) para analisar a dominância, constância e similaridade. Um total de 68 espécies (32 Characiformes, 32 Siluriformes, 2 Gymnotiformes e 2 Perciformes) e 2.758 exemplares foram capturados. O trecho com maior riqueza de espécies foi Tibagi abaixo (50 espécies), seguido por Tibagi acima (40 espécies), Iapó (35) e Fortaleza (14). No Fortaleza ocorreu o menor número de espécies, mas foi verificada a maior abundância, com 508 dos 877 exemplares capturados pertencentes à espécie Astyanax paranae, o que elevou o índice de dominância desse local para 37,9 por cento. As dez espécies mais abundantes corresponderam a 65,5 por cento do total de exemplares coletados, apresentando uma proporção que variou de 3,9 a 18,6 por cento. Do maior para o menor percentual, as espécies foram A. paranae, Astyanax fasciatus, Prochilodus lineatus, Hypostomus sp. I, Hypostomus regani, Rhamdia quelen, Astyanax eigenmanniorum, Apareiodon ibitiensis, Apareiodon affinis e Leporinus amblyrhynchus. Quanto à freqüência de ocorrência, 25 espécies foram capturadas em apenas um dos trechos; 11 em dois trechos; 25 em três; e apenas R. quelen, A. ibitiensis e A. affinis foram capturadas em todos os trechos. Muitas espécies migratórias foram capturadas, destacando-se P. lineatus e Salminus brasiliensis. A ictiofauna de Fortaleza, Iapó, Tibagi acima e Tibagi abaixo diferiu significativamente em riqueza de espécies, indicando que as assembléias de peixes são diferentes entre os trechos. Da análise de similaridade de Bray-Curtis, verificou-se maior similaridade entre Tibagi acima e Tibagi abaixo, seguido por Iapó e, finalmente, Fortaleza. Já pela análise de similaridade de Jaccard, a maior similaridade foi entre Iapó e Tibagi acima, depois Tibagi abaixo e Fortaleza.

The ichthyofauna of four stretches of rio Tibagi hydrographic basin was monthly sampled from May 2001 to April 2002, with gillnets (totalling 1,000 m²) in order to analyze the dominance, constancy and similarity indexes. A total of 68 species (32 Characiformes, 32 Siluriformes, 2 Gymnotiformes and 2 Perciformes) and 2,758 individuals were captured. The stretch with greatest richness of species was Tibagi abaixo (50 species), followed by Tibagi acima (40 species), Iapó (35) and Fortaleza (14). In Fortaleza occurred the smallest number of species, but the greatest abundance was verified with 508 of 877 captured individuals of Astyanax paranae, what elevated the place's dominance index to 37.9 percent. The ten more abundant species corresponded to 65.5 percent of the total specimens collected, presenting a proportion that varied from 3.9 to 18.6 percent. From the greatest to smallest percentage, the species were A. paranae, Astyanax fasciatus, Prochilodus lineatus, Hypostomus sp. I, Hypostomus regani, Rhamdia quelen, Astyanax eigenmanniorum, Apareiodon ibitiensis, Apareiodon affinis and Leporinus amblyrhynchus. In frequency of occurrence, 25 species were captured in only one of the stretches; 11 in two stretches; 25 in three; and only R. quelen, A. ibitiensis and A. affinis were captured in all of the stretches. Many migratory species were captured, with highlight to P. lineatus and Salminus brasiliensis. The ichthyofauna of Fortaleza, Iapó, Tibagi acima and Tibagi abaixo differed significantly in richness of species, indicating that the fish assemblages are different among stretches. From similarity analysis of Bray-Curtis among stretches, the greatest similarity was verified among Tibagi acima and Tibagi abaixo, followed by Iapó and, finally, Fortaleza. On the other hand, in similarity analyses of Jaccard, the greatest similarity was among Iapó and Tibagi acima, followed by Tibagi abaixo and Fortaleza.

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