Observation on dynamics of ecosystem and material cycling in Otsuchi Bay

Fiscal Year

2015

Title

Observation on dynamics of ecosystem and material cycling in Otsuchi Bay

Project and Theme

Project 2. Studies on the Mechanisms of Marine Ecosystem Change
Representative Organization: Atmosphere and Ocean Research Institute The University of Tokyo
Theme3. Study on material circulation process changes accompanying the earthquake
Representative personToshi Nagata
OrganizationAtmosphere and Ocean Research Institute The University of Tokyo
DepartmentDepartment of Chemical Oceanography, Marine Biochemistry

Research Information

Period and Interval
2015/04/01 - 2016/03/31
Once for two months
Research Area
Otsuchi Bay
Category
Field survey
Overview
Bimonthly observation at Otsuchi Bay is planned to reveal effect of the Great East Japan Earthquake. 7 sampling stations will be established covering inner half area of Otsuchi Bay from center of the bay to mouse of Unosumai River. CTD observation will be conducted at all sampling station. Water sample organisms will be collected from some depth layers at selected 4 stations within the 7 stations by Niskin bottle. Sediment sampling will be conducted collected from surface of sea floor at selected all stations by Smith-Mcintyre sampler. River water for nutrient analysis will be also collected from the surface of Otsuchi, Kozuchi and Unosumai River.

Overview of the Observation

Research Point Table
Point
Name2
Coordinates39.343,141.946
Name4
Coordinates39.335,141.939
Name6
Coordinates39.341,141.93
Name8
Coordinates39.349,141.918
Name11
Coordinates39.336,141.913
Name16
Coordinates39.333,141.902
NameM (Ex. 1)
Coordinates39.363,141.99
NameO1
Coordinates39.364,141.9025
NameK1
Coordinates39.35695,141.8933
NameU1
Coordinates39.3315,141.8858
Research Point Map & Track Chart Map & Point List
0094_R01.png
Results and Future Plan
Observation was conducted on 26/May, 21/Jul, 15/Sep, 18/Nov/2015, 14/Jan, and 7/March/2016 by R/V Grand Maillet. We obtained vertical profiles of water temperature and salinity, water samples for analysis of nutrients, chlorophyll a, dissolved organic carbon/nitrogen, particulate organic carbon/nitrogen, abundances of virus, prokaryote and protist and related environmental parameters and sediment samples for analysis of organic carbon/nitrogen content. CTD observation was conducted at all sampling station. Water samples were collected from several layers from the surface to the bottom at Station M, 2, 6, 11 and 16. River water for nutrient analysis was collected from the surface of three rivers. Sediment samples were collected at station M, 2, 4, 6, 8, 11 and 16. The observation will be held once for two months in the next fiscal year.

Investigation Item and Data Acquisition

Investigation ItemData Acquisition
Water propertyTemperature, salinity, concentrations of chlorophyll a, dissolved organic carbon/nitrogen and particulate organic carbon/nitrogen and related physicochemical environmental parameters
Planktonic oragnismAbundances of virus, prokaryote and protist
Sediment propertyOrganic carbon/nitrogen contents

Reference

Related Observation Plan
FY2015 Observation on dynamics of ecosysytem and material cycling in Otsuchi Bay.
Related Observation Data
Observations of Otsuchi Bay

Person in charge of Investigation

Representative personHideki Fukuda
OrganizationAtmosphere and Ocean Research Institute The University of Tokyo
DepartmentInternational Coastal Research Center, Coastal Conservation

Keywords

Fiscal Year2015
OrganizationAtmosphere and Ocean Research Institute, The University of Tokyo
CategoryField survey
Research AreaSouth Sanriku
DisciplineOcean physics -> Water temperature
Ocean physics -> Salinity
Ocean chemistry -> Salinity
Ocean chemistry -> Nutrients
Ocean chemistry -> Organic matter
Ocean environment -> Nutrients
Ocean environment -> Plant pigments
Ocean environment -> Transparency
Ocean environment -> Organic carbon
Ocean environment -> Organic nitrogen
Ocean environment -> Seawater
Ocean environment -> Suspended solids
Ocean environment -> Sediment
Ocean biology / Ocean ecology -> Biomass
Ocean biology / Ocean ecology -> Viruses
Ocean biology / Ocean ecology -> Bacteria
Ocean biology / Ocean ecology -> Archaea
Ocean biology / Ocean ecology -> Protists