Submarine sediment distribution and its controlling factors around the western areaoff Tokara Islands and southern area off Yakushima Island

A comprehensive analysis of submarine sediment distribution around the western Tokara Islands and southern Yakushima Island reveals strong influences from the Kuroshio Current on both geological and biological processes. The study, conducted through 95 surface sediment sampling points and one core sample, found that sediment types—ranging from coarse sand to mud—are shaped by abundant fine-grained material supplied from surrounding landmasses and localized bottom currents. In Yakushima's southern region, extensive rock exposures along ridge lines and the presence of biogenic debris in sandy sediments suggest intensified erosion and sediment movement linked to Kuroshio Current dynamics. Analysis of foraminifera, coral distributions, and environmental DNA further indicates that biological productivity is closely tied to these oceanographic factors.

SUZUKI, Y., ITAKI, T., KATAYAMA, H., KANEKO, N., HARIGANE, Y., SAITO, N., IWATANI, H., MATSUI, H., ISHIZUKA, O., YAMASAKI, M., ARIMOTO, J., TOKUDA, Y., SENTOKU, A., IKEUCHI, E., IGUCHI, A., SUZUKI, A., & SEIKE, K. (2024). トカラ列島西方海域及び屋久島南方海域の底質分布とその制御要因. Bulletin of the Geological Survey of Japan, 75(5-6), 223–248. https://doi.org/10.9795/bullgsj.75.5-6_223