Hyun Je Parka, Jung Hyun Kwaka,b, Hee Yoon Kangb, Kee-Young Kwonc, Weolae Limd, Chang-Keun Kangb,*
aDepartment of Marine Bioscience, Gangneung-Wonju National University, Gangneung 25457, Republic of Korea
bSchool of Earth Science & Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
cResearch and Development Planning Department, National Institute of Fisheries Science, Busan 46083, Republic of Korea
dOcean Climate and Ecology Research Division, National Institute of Fisheries Science, Busan 46083, Republic of Korea
Harmful algal blooms involving the dinoflagellate Cochlodinium polykrikoides occur every summer off the Korean peninsula's central southern coast. To determine whether Cochlodinium bloom-derived organic carbon is incorporated into the subtidal macrobenthic food web, we compared the δ13C and δ15N values of suspended particulate organic matter (SPOM) and sedimentary organic matter, and macrobenthic consumers between bloom and non-bloom seasons. Chemotaxonomic analysis revealed the presence of Cochlodinium blooms in summer and a predominance of diatoms in autumn. Both the δ13C and δ15N values of SPOM were higher in the bloom than in the non-bloom seasons. Such temporal shifts in the δ13C and δ15N values were also observed for most macrobenthic consumers collected in both seasons. Consistent temporal isotopic shifts in SPOM and macrobenthos revealed that the Cochlodinium bloom-derived carbon was incorporated into the coastal benthic food web, resulting from its increasing availability during blooms.