瀬戸内海全域にわたり、1993年10月、1994年1、4、6月に4回の海域環境と低次生物生産に関する総合的観測調査を行った。これらのうち、ここでは底質に関する調査結果をとりまとめた。各調査では瀬戸内海全域にわたり15～20測点において採泥し、海底直上水中の溶存酸素量、底泥の温度、含水率、強熱減量、pH、酸化還元電位、酸揮発性硫化物量を測定した。

Sediment qualities were analysed at 15-20 stations in the Seto Inland Sea during four cruises in October, 1993, January, April and June, 1994. Surface sediment was collected at each station, and temperature, pH, oxidation-reduction potential, water content, acid volatile sulfide and ignition loss of the collected sediment were determined along with dissolved oxygen concentration in the overlying water of the sediment. Seasonal and regional variations of sediment quality were reported.