Data from: Differences in subtidal macrobenthic community structures and influencing factors between Jindo and Jeju Islands in South Korea

Although islands in South Korea have been significantly impacted by human
activities, marine ecological studies focusing on island coasts have been
limited. Due to their distinct characteristics, Macrobenthos are
extensively utilized to assess the impact of anthropogenic influences on
the marine environment. In August 2010, August 2011, and September 2012,
samples of macrobenthic communities, bottom water, and sediment were
collected from the subtidal zones around southern Jindo and northern Jeju
Islands. Macrobenthos were identified to the species level using a
stereomicroscope. Bottom seawater quality was evaluated, with a focus on
dissolved heavy metal concentrations (As, Cr, Cd, Cu, Pb, and Zn).
Additionally, we measured the organic matter content and mean grain size
of the sediment. There were marked differences in macrobenthic community
structures between the two islands, including the number of species,
species abundance, species richness index, and Pielou’s evenness index
(p<0.05). Cluster analysis and Non-metric analysis revealed
variations in macrobenthic communities between the two islands and over
the years 2010, 2011, and 2012. According to the Biota-Environment
Matching (BIO-ENV), distance-based redundancy analysis (dbRDA), and
Distance-based Linear Model analyses, the principal environmental
variables influencing the distribution of macrobenthic communities are Cd
and As. These variations likely result from different levels of human
activity on each island. Moreover, interannual variations in macrobenthic
communities, especially in 2012, were predominantly influenced by Pb and
Cr, likely due to alterations in the influence of the Changjiang diluted
water.