Station-level sediment chemistry and macrobenthic density data from shellfish-farming grounds in Yeojaman Bay, South Korea, September 2023

This dataset contains station-level environmental measurements and macrobenthic density records from 15 shellfish-farming stations in Yeojaman Bay, South Korea, sampled in September 2023. Ten northern stations (N1–N10) correspond to Boseong ST-1–ST-10; five middle stations (M1–M5) correspond to Goheung area 2 ST 2-1–ST 2-5. The data accompany the manuscript “Sediment metal contamination and associations with macrobenthic communities in shellfish farming areas of Yeojaman Bay, Korea”. The deposit includes the 40-taxon analytical density matrix, 19 environmental variables including seven sediment metals, station metadata, the recorded taxon inventory, archived diversity summaries, source worksheet excerpts, a variable dictionary and provenance information. Source excerpts retain original blank cells; the separately labelled analytical matrix treats those blanks as zero, as in the manuscript analysis. TOC values were verified individually against matching source records and are expressed as percent dry sediment mass. The three principal data tables are also supplied in an Excel workbook. Data quality notes: biological values are reported station densities (ind. m−2), not original grab-level counts. Their numerical conversion remains unresolved: the author confirms two 0.05-m2 grabs pooled over 0.10 m2, whereas some archived values occur in increments of 5 ind. m−2. Sigambra hanaokai at M4 is blank in the analytical source but equals 5 ind. m−2 in the regional source; both versions are preserved. These discrepancies have not been silently corrected or rescaled. The README and data_issues.csv describe the source versions, method qualifications and conditions for reuse. Original grab-count sheets and instrument output files were not available.