Characteristics and Ecosystem Changes of Marine Algal Communities in Wangdol-cho on the East Coast of Korea

Abstract

This study sought to examine the characteristics and patterns of marine algae community changes in Wangdol-cho in order to establish a theoretical basis for the development of a maintenance and management plan for the marine communities of the region. Here, two locations were selected to represent marine algal communities in both spring and summer from 2017 and 2018, and the covering ratio (%) by algae type was recorded. During the study period, 114 marine algae species were identified at the survey sites, which were further classified as 8 green, 18 brown, and 88 red algal species. The total average biomass in the survey period was found to be 1,383.17 g/m2, including green (2.40 g/m2), brown (987.40 g/m2), and red (393.36 g/m2) algae. Cluster analysis of the communities was conducted on three groups: Group A (Spring 2017 and Spring 2018), Group B (Summer 2017), and Group C (Summer 2018). ANOSIM analysis showed a significant difference for the biomass data associated with the season with a global-R value of 0.717 (p = 0.002). The community status was determined as ‘Good-High’ for the three survey periods except for the summer of 2017 which showed ‘Good-Moderate’. Among the cluster indices calculated based on the number of abundant species, the R/P ratio ranged from 3.14 to 11.25, and the (R+C)/P ratio ranged from 3.29 to 12.00. Richness, evenness, diversity, and dominance indices were based on the biomass of abundant species, and were determined as 15.35, 0.36, 1.68, and 0.31 over the entire sea area, respectively. The results of this survey indicate that the marine algal community in the Wangdol-cho area is suffering from severe barren grounds due to non-geniculate coralline coverage of the rock matrix, as well as turf-forming red algae. Therefore, further resource and ecological analyses will be required to establish a plan to restore and manage the ecosystem of Wangdol-cho to maintain a healthy marine ecosystem and algal resources.