Main drivers of dragonflies and damselflies (Insecta; Odonata) metacommunities in streams inside protected areas in the Brazilian Amazon.

The evaluation of environmental and spatial influence in freshwater systems is crucial for the conservation of aquatic diversity. So, we evaluated communities of Odonata in streams inside and outside sustainable use areas in the Brazilian western Amazon. We predicted that these streams would differ regarding habitat integrity and species α and ß diversity. We also predict that environmental and spatial variables will be important for both suborders, but with more substantial effects on Zygoptera species, considering their nature of forest-specialist. The study was conducted in 35 streams, 19 inside and 16 outside sustainable use areas. The streams outside presented high species richness, abundance, and number of exclusive forest-specialist species from Zygoptera and higher scores of habitat integrity. In contrast, one sustainable use area presented the lowest values of these metrics. Besides, we found that environmental and spatial variables were significantly associated to Zygoptera species composition, but not with Anisoptera, which can be explained by their cosmopolitan nature. Our results indicated that an interplay between environmental and spatial processes determines the structure of the metacommunities of Zygoptera. The less effective dispersal rates and narrow ecological tolerance of Zygoptera species make them more influenced by local conditions and dispersal limitation, and more sensible to habitat modifications. We highlight the importance of improving the local management of the sustainable use areas by environmental agencies, mainly on areas that are losing their capacity to maintain the aquatic fauna, and implementation of social policies toward traditional people.

Concordance between macroinvertebrate communities and the typological classification of white and clear-water streams in Western Brazilian Amazonia / Concordância entre comunidade de macroinvertebrados e classificação tipológica de igarapés em águas brancas e claras no oeste Amazônico, Brasil

In this study we have attempted to answer whether there is correspondence between aquatic macroinvertebrate communities and the typological classification of white and clean-water streams in western Amazonia lowlands. We worked within two distinct hydrographic basins: Moa River catchment (clear-water streams) and Azul River catchment (white-water streams) in Serra do Divisor National Park, Acre State, Brazil, sampling 10 streams in each basin. A total of 2,952 individuals were collected, distributed among 134 taxa. Our results show that macroinvertebrate communities, at genus as well as family level, are in concordance to a priori classifications that distinguish between white and clear water streams. The main implication of our results for biomonitoring is that biotic variation between white and clear streams can be partitioned regionally, which would improve the bioassessment accuracy of the Amazonian streams.

Neste trabalho, nós investigamos se há correspondência entre comunidade de macroinvertebrados e classificação de igarapés em águas claras e brancas no oeste da Amazônia. Nós trabalhos em duas bacias hidrográficas, Rio Moa (águas claras) e Rio Azul (águas brancas) no Parque Nacional da Serra do Divisor, Acre, Brasil, amostrando 10 igarapés em cada bacia. Coletamos 2952 indivíduos, distribuídos em 134 taxa. Nossos resultados mostram que a comunidade de macroinvertebrados, identificada com baixa e alta resolução taxonômica, responde claramente a classificação tipológica de igarapés em águas claras e brancas.A principal implicação dos nossos resultados no âmbito de biomonitoramento é que a partição da variação biótica entre igarapés de águas claras e brancas pode melhorar a racionalidade e implantação de sistemas de avaliação ambiental na Amazônia.