Resumo A regularização de rios tem papel fundamental para o desenvolvimento socioeconômico de uma região, porém resulta em alterações em larga escala no regime de fluxo natural e modifica potencialmente uma ampla gama de fatores abióticos e bióticos, sendo considerado um dos impactos ambientais mais significativo nos rios em todo o mundo. Este estudo tem como objetivo avaliar os impactos na comunidade de macroinvertebrados ocasionado pela construção de uma barragem para armazenamento de água no rio Poxím-Açú, bem como características biológicas e ecológicas locais. Foram realizadas coletas de macroinvertebrados em três pontos a jusante da barragem em dois períodos distintos: anterior a construção da barragem (2013) e posterior a barragem (2015). A qualidade da água foi classificada como de boa e excelente qualidade, respectivamente, por meio dos índices bióticos. Alterações nas comunidades de macroinvertebrados foram observadas devido as modificações do regime de vazão, como resultado da construção da barragem, que influenciou na composição e estrutura das comunidades de macroinvertebrados e se reflete nas mudanças na diversidade, equitabilidade, riqueza e número de indivíduos no período anterior e posterior a barragem.

Abstract River regularization plays an important role in socio economic development. However, it also modifies the natural flow system of the river and its biotic and abiotic characteristics, causing significant impacts on rivers. To evaluate the impacts on the macroinvertebrate community caused by dam construction on the Poxim-Açú River, metrics of composition and community structure of the macroinvertebrates were analyzed, as well as ecological and biological traits of the region. Macroinvertebrates were collected at three sites located downstream the dam, before (2013) and after (2015) dam construction. The water quality was classified as “good” to “excellent” according to the biotics indices. The alterations of the flow regime of the river after the dam construction influenced the macroinvertebrate communities, modifying their diversity, equitability, richness, and the number of individuals.

Abstract On this study, we used camera traps in a Semi deciduous Seasonal Forest, northeast of Brazil, to estimate the frequencies of occurrence of two Neotropical herbivorous mammals: the spotted paca (Cuniculus paca) and the tapeti (Sylvilagus brasiliensis), analyzing their seasonal variations of spatial distribution. We also characterized the activity pattern of the species and their seasonal variation. The herbivorous frequencies of occurrence were constant during all the seasons. In general, both species were mostly active at night. However, between the rainy and dry season, we identified differences in spotted paca activity peaks. Here we present one of the first studies on the tapeti, whose ecology is understudied. Our results also show a general view of the spotted paca and tapeti behavior strategies to seasonal variations. Due to the scarce food resource in the dry season, possibly these herbivorous need to search for different kinds of food available IFS around.