Independent and interactive effects of humic substance supplementation, temperature and UVB on free-living and host-associated coral reef bacterial communities

In the present study, we assessed both free-living (sediment and seawater) and host-associated bacterial communities from a number of benthic coral reef taxa, including two hard corals (M. digitata and M. capricornis), one soft coral (S. glaucum), one zoanthid (Zoanthus sp.) and one sponge (Chondrilla sp.) using 16S rRNA gene amplicon sequencing. All organisms were maintained in aquaria under ambient conditions prior to use in a multifactorial microcosm experiment where we investigated the interactive and independent effects of humic substances, temperature and UVB radiation on several coral reef species in addition to sediment and water.