Spatiotemporal Changes in the Macrophytobenthos in the Coastal Zone of Karanskii Nature and Landscape Reserve (Sevastopol, Black Sea)

• Published in: Biology bulletin of the Russian Academy of Sciences 2021-12, Vol.48 (10), p.1941-1949
• Main Authors: Mironova, N. V., Pankeeva, T. V.
• Format: Article
• Language: English
• Subjects: Algae; Aquatic plants; Biochemistry; Biodegradation; Biomass; Biomedical and Life Sciences; Cell Biology; Coastal zone; Comparative analysis; Deposits; Dominant species; Ecology; Epiphytes; Eutrophic environments; Life Sciences; Macrophytes; Marine flora; Phyllophora crispa; Preservation; Species diversity; Vegetation; Zoology
• ISSN: 1062-3590; 1608-3059
• DOI: 10.1134/S1062359021100320

—For the first time, the landscape approach was used to conduct a comparative analysis of the macrophytobenthic species diversity and changes in its biomass in the coastal zone of Karanskii Nature and Landscape Reserve over the period of 1964–2016. A landscape map of the submarine nearshore slope was produced, and three benthic natural complexes (BNCs) have been distinguished. The main such complex is the BNC of psephitic deposits with the predomination of Carpodesmia crinita and Treptacantha barbata (up to 89.7% of the total macrophyte biomass). The complex is distinguished by a high floristic diversity and the maximum macrophytobenthic biomass. The BNC of psephitic deposits predominated by C. crinita and Tr. barbata with alternating pebble–gravel deposits and broken shells predominated by Phyllophora crispa is distinguished by the highest floristic diversity and lower shares of C. crinita and Tr. barbata ; the share of Ph. crispa in the total macrophyte biomass amounts to 14.4%. The BNC of psammitic deposits with the predomination of Ph. crispa and with individual randomly scattered blocks where Nereia filiformis and Zanardinia typus predominate features a low floristic diversity, the predominance of Phyllophora crispa (74.3% the total macrophyte biomass), and good preservation of perennial species. Over the course of more than 50 years, the plant component underwent restructuring and degradation in all BNCs of the reserve (at depths of 0.5–10 m). Apparently, this can be explained by the intensification of anthropogenic activities in the coastal zone. Eudesme virescens , Dictyota dichotoma , Feldmania irrgularis , Dasya baillouviana , and Rhodochorton purpureum inhabiting clean open coastal areas disappeared from the benthic vegetation; while macrophytes typical for eutrophic waters ( Cladophora laetevirens , Ectocarpus siliculosus , and C. virgatum ) appeared there. The biomass of epiphytes has sharply increased from 0.1 to 42.6% of the total macrophyte biomass, while the role of dominant species decreased: the share of C. crinita and Tr. barbata dropped from 99.9 to 78.6% of the total macrophyte biomass; the share of Ph. crispa , from 52.9 to 14.4%. The designation of Karanskii Reserve contributed to the preservation and partial restoration of the unique natural complex of marine flora and benthic vegetation; the increased floristic diversity of algae acting as indicators of clean waters and the increased share of Red Data Book species confirm this.