Effect of the mining pipeline on habitat quality and the diversity of semiaquatic bug communities (Heteroptera: Gerromorpha) in streams of the eastern Amazon

Assessing how the disturbances affect the physical structure and biodiversity of freshwater ecosystems has become a critical research priority. Bauxite mining is economically important in the Amazon, but associated infrastructure may influence freshwater biodiversity. We evaluated the effects of a bauxite ore pipeline on the community structure of semiaquatic bugs (Heteroptera: Gerromorpha) in 40 streams of the eastern Amazon, including 20 sites crossed by the pipeline and 20 control sites. We tested whether (i) species abundance and richness upstream and downstream of control sites would be higher than in pipeline sites, (ii) upstream sites would show greater abundance and richness due to species sensitivity and habitat alteration in sites crossed by the pipeline, (iii) community composition would differ between pipeline and control sites, with characteristic species for each treatment, and (iv) the pipeline would indirectly influence communities through changes in habitat quality, riparian cover, and abiotic variables. Multivariate analyses indicated clear differences in community composition, with indicator species characterizing each condition, including the species Rhagovelia jubata in pipeline streams and Stridulivelia alia and Stridulivelia strigosa in control streams. Abundance showed a tendency to be higher in control streams, whereas richness was associated with abundance but not with habitat integrity. These findings indicate that, although diversity metrics remained similar, pipeline installation is linked to changes in species composition, reflecting shifts in local environmental conditions.