SEASONAL SUCCESSIONS OF BENTHIC MACROINVERTEBRATE COMMUNITIES IN THE BOSNA RIVER IN THE AREA OF THE CITY OF ZENICA

This research describes seasonal successions of the qualitative-quantitative composition of benthic macroinvertebrate communities in the Bosna River in the area of the city of Zenica. Collection of benthic macroinvertebrates was conducted from October 2014 to May 2015 at 5 measurement locations along the course of the Bosna River in the city of Zenica. Biological diversity indices (Shannon–Weaver index, Simpson's index), a species evenness indicator, and Bray–Curtis cluster analysis was used for data analysis. The study of benthic macroinvertebrates identified 34 taxa and 4224 individuals, with a dominance of preimaginal stages of aquatic insects with 21 taxa. The highest observed Shannon–Weaver diversity index was 2.26 in the spring aspect at the Balnozi site, while the lowest was 0.27 in the summer aspect at the Raspotočje site. Using the Simpson's index, values ranged from 0.07 in the summer period at the Raspotočje site to 0.82 in the winter period at the Balnozi site. Analysis of species evenness between communities at the investigated sites revealed similarity in benthic fauna between the first (0.64) and second (0.67) sites, as well as between the fourth (0.76) and fifth (0.70) sites. According to the results of the cluster analysis, the investigated sites have similar macroinvertebrate communities classified by seasons of benthic macroinvertebrate examination.