Пространственно‐временные изменения макрофитобентоса бухты Круглая (Черное море)

Abstract

Aim . The aim of the present study is a comparative analysis of spatio ‐ temporal changes in the macrophytobenthos of Kruglaya Bay over a 40 ‐ year period (1977 ‐ 2018) using a landscape approach. Material and Methods . Submarine landscape research of Kruglaya Bay was carried out in the summer of 1977 and 2018 by the method of detailed study of the bottom using landscape profiling. The landscape mapping of Kruglaya Bay waters was done based on the constructed profiles and interpretation tables Results . This research presents for the first time through landscape mapping the results of a comparative analysis of qualitative and quantitative changes in the plant components of BNC (bottom natural complexes) carried out in Kruglaya Bay over a period of more than 40 years. Conclusions . Comparative analysis showed that the composition, structure and distribution of bottom vegetation have marked significant changes. For the BNC upper shoreface abrasion slope composed of psephitic sediment, the dominance of Cystoseira species (the share of which decreased from 76 ‐ 99 [1977] to 55 ‐ 92% [2018] of the total biomass of macrophytes) is characteristic. The most noticeable changes in the BNC occurred in the gently dipping accumulation plain composed of silt ‐ psammitic sediments, where the dominant community was seagrass throughout the study period with its contribution accounting for 96 ‐ 99% of total macrophyte biomass. It was revealed that a change in the Zostera ‐ based phytocoenoses occurred Zostera marina dominating with Z. noltei co ‐ dominant to Zostera‐Stuckenia ‐ based phytocoenoses where Z. noltei and Stuckenia pectinata predominate. The changes in the structure and composition of the macrophytobenthos of Kruglaya Bay are probably associated with the influence of both natural and anthropogenic factors.