Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8528, Japan
The sediment quality of Hiroshima Bay and the neighboring area, Suo Nada, was compared using 5 years' monitoring data. Water content (WC) and ignition loss (IL), which is an index of organic matter, were significantly higher in the Hiroshima Bay sediment than in the Suo Nada sediment. Acid-volatile sulfide (AVS) content was also higher in the Hiroshima Bay sediment in winter and spring. While WC and IL showed almost no seasonal change in both areas, AVS showed the maximum in autumn and oxidation-reduction potential (ORP) was low in summer and autumn. These differences of the sediment quality in the two areas are discussed in terms of differences in social background, area usage and oceanographic structures.