Effects of floods on macroinvertebrate communities in the Zarin Gol River of northern Iran: implications for water quality monitoring and biological assessment

Abstract Background The timing, magnitude, and duration of extreme hydrological disasters have the potential to threaten species diversity river habitats. On August 8, 2014, 19, 2017, disastrous floods struck mountainous regions Iran’s Zarin Gol River basin. Macroinvertebrate communities were studied at seven upstreams prior in June 2014 2017 after September 9 months second flood 2018. effects on macroinvertebrate communities, recovery rate community resilience influencing factors investigated. Results Despite fact that only reason disruption, biological water quality assessment metrics disaster comparable those heavily polluted waters. Biological indicators revealed unaffected floods, remained within acceptable limits. Following disasters, density macroinvertebrates declined, demonstrated severe depletion quality. Community (species richness, percent model affinity (PMA), Ephemeroptera, Plecoptera, Trichoptera (EPT) richness) rebounded (June 2018), demonstrating River’s could recover even impact floods. As a result, samples taken from flood-affected areas flooding, rather than decrease quality, causes loss abundance. Conclusion Because shifts regimes streams around world, understanding short-term impacts strong flooding comparatively quick ecosystems has important consequences for bio-assessment programs