Publication Date:
2022-05-31
Description:
The influence of eutrophication on the occurrence of the red algae Furcellaria lumbricalis and Phyllophora truncata was studied in the sea area of Turku. Due to increased sediment load and planktonic production, light penetration in the water has decreased in the northern parts of the study area. Furthermore, the quality of the sea bottom has changed. Plots of 1 m2 (N = 100} in the upper littoral zone (0.5-6 m} were studied by SCUBA diving, in order to investigate the factors controlling the occurrence of the red algae. Two transects were situated in the eutrophicated area, and two in the reference area. In the plots, the percentage cover of each plant species and of Mytilus edulis was documented, and the Secchi disc visibility and depth was measured. The numerical data were analyzed by correlation analysis and stepwise multiple regression analysis (BMDP2R}. In the eutrophicated area, abiotic factors (percentage cover of plain bottom and bottom quality} explained 81.28 % of the variation of red algae cover. In the reference area, the biotic factors (total number of species and Mytilus cover in %} were the most important factors, explaining 66.4 % of red algae cover.
Type:
Article
,
NonPeerReviewed
Format:
text
