Ant assemblages (Hymenoptera: Formicidae) from areas under the direct influence of two small hydropower plants in Brazil

Abstract

Current energy production has been the subject of studies on
 environmental impacts and the need to adequately understand that the
 relationship to biodiversity loss is growing. One of the ways of assessing
 environmental changes is the use of bioindicator species, and ants
 represent an alternative in this regard. This study aimed to evaluate
 ant assemblages occurring in different environments in areas under the
 direct influence of two small hydropower plants (SHPP). Sampling was
 carried out using pitfall traps in forest and agricultural fragments, as
 well as pasture areas, along the Andrada River, municipality of Cascavel,
 state of Paraná, in July 2016 and March 2017. The sampled ant
 assemblages were evaluated for richness, abundance, and composition.
 The rarefaction analysis was used to compare the richness sampled in
 the two areas under direct influence. Abundance was analyzed based
 on the number of occurrences. The nonmetric multidimensional scaling
 (NMDS) was applied to test whether the abundance and composition
 of ant assemblages differ at the same site when sampled in both
 seasons. In total, 63 species belonging to 23 genera and 6 subfamilies
 were identified. The subfamily Myrmicinae was the most speciesrich
 (S = 25), followed by the subfamily Formicinae (S = 21). The most
 species-rich genus was Camponotus (S = 15) followed by Pheidole
 (S =11). A total of 41.3% richness was registered concurrently in the two
 assemblages. The study contributes to the expansion of knowledge of
 the ant fauna occurring in the state of Paraná and serves as a basis for
 monitoring impacts caused by the implementation of SHPP and other
 developments.