FIELD OBSERVATION OF AQUATIC ENVIRONMENT IN MIYAKO BAY, IWATE, JAPAN AFTER THE GREAT EAST JAPAN EARTHQUAKE

Abstract

 Auatic environment in Miyako Bay, Iwate, Japan after the Great East Japan Earthquake has been still unknown because no field observation of it has been conducted after the earthquake. Therefore, we conducted field observations of water temperature, salinity, turbidity, dissolved oxygen and chlorophyll a at 0.1 m vertical intervals for 24-28 locations in the bay in September and December, 2013 using a portable multi-item water quality analyzer.
 The observed results revealed the characteristic feature of aquatic environment in the bay including the existence of low salinity water masses around Hei and Tsugaruishi rivers due to freshwater inflow and around the center-east part of the bay. The results also showed that sea surface distributions of chlorophyll a and turbidity have changed greatly within 6 hours.