Anchialine cave 16S amplicon sequences and metagenomic dataset

Defined clines in anchialine ecosystems act as selection barriers that influence species distributions. Along with light resources and nutrient limitations, cline areas are recognized promoters of microbial evolution in these complex habitats. To reveal microbial diversity and its potential ecological role in biogeochemical cycles along a salinity gradient, we sampled different water masses and analyzed microbial diversity. The stable halocline promoted sulfide accumulation in anoxic (euxinic) water layers situated between the oxic surface layer (characterized by lower salinity and influenced by precipitation) and the seawater layer (characterized by oxygen-saturated seawater with high salinity entering the cave). Sequencing was performed at the Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna under the project ID JMF-2110-14.