Studies on the Survey of Sea Water Pollution along the Seashore of Kei-yo Industrial Area. II. Variations of Pollution Indicators at Each Sampling Station, with the Lapse of Four Seasons and Behaviors of Them in Akashio

Abstract

Survey of sea water pollution along the seashore of Kei-yo industrial area (Chiba Prefecture) was carried out during 12 years from 1965 to 1976. Variations of pollution indicators at each sampling station with the lapse of four seasons and their behavior in Akashio (red tide), were examined. Maximum of sea water pollution was observed in the northeast Kei-yo industrial area. Seasonally, at summer, maximum of pH, COD, and SS, and minimum of NH₄-N, NO₂-N, and PO₄-P, were observed. In Akashio, the value of COD increased remarkably and NH₄-N, NO₂-N, and PO₄-P, decreased extremely.