Cladophoraspp. (Chlorophyta) modulate environment and create a habitat for microalgae in hypersaline waters

Cladophoraspp. constantly or periodically form floating and benthic mats in Crimean hypersaline lakes and lagoons. In 2017-2018, characteristics of theCladophoramats and the microalgae onCladophorafilaments were studied employing field research and microscopy. The wholeCladophoramat has a vertical structure, including the upper and lower layers of the floating mat and benthic mat. In total, 50 species of microalgae were found: 40 of them belonged to Bacillariophyta (Bacillariophyceae and Mediophyceae), two to Haptophyta (Coccolithophyceae), four to Miozoa (Dinophyceae), one to Chlorophyta (Zygnematophyceae) and three to Cyanobacteria (Cyanophyceae). Floating layers of the mat differed significantly in species composition from the benthic mat. The total abundance of microalgae and their biomass onCladophora(per unit area of filaments) varied widely within sampling sites from 3.79 x 10(6)to 5.04 x 10(8)cells m(-2)and 2.6 to 2197.8 mg m(-2). The total mass of microalgae achieved more than 32% of the mass ofCladophora, averaging 7.7% (standard deviation = 13.3).

Automated summary

The study found that Cladophora forms floating and benthic mats in Crimean hypersaline lakes and lagoons, with a diverse range of microalgae species. There were differences in species composition between the floating and benthic mats. The abundance and biomass of microalgae on Cladophora varied significantly, with microalgae accounting for a considerable proportion of Cladophora's mass.