Projet Grand Maillet is named after the first new research vessel built for the International Coastal Research Center in Otsuchi since the disaster. The name of Otsuchi town means ‘big maillet’ in English and ‘grand maillet’ in French.

Studies on the mechanisms of marine ecosystem change Otsuchi Bay, Sanriku coastal region

(PGM Director: Kazuhiro Kogure)

Study on the disaster’s impact on the ecology and resources of living organisms in the coastal area, as well as elucidation of the subsequent recovery process. Highlighting the steps needed to restore the fishing industry by means of continuous observation and monitoring.

1. Construction of a monitoring system for the coastal region, and the establishment of the Marine Analysis Center

(Principal Investigator: Atsushi Tsuda)

Our task is to continuously monitor the marine environment 0f the Otsuchi Bay and its surrounding area and create a system to collect information in real time. In addition, we will establish a center to adopt unified high sensitive methods for analyzing diverse samples gathered during the project.


2. Study on the disruption to and the subsequent recovery process of the ecosystem hit by the earthquake and tsunami

(Principal Investigator: Tomohiko Kawamura)

The earthquake and tsunami caused the disturbance of marine ecosystems. (The impacts varied in scale depending on the coastal landforms.) It had an effect on a number of factors, such as the distribution, habits, and behavior of the living organisms in the region. By combining the knowledge and skills of various specialists, our continuous research on numerous subjects will clarify the impact of the disaster, as well as possible steps in the process towards recovery.


3. Study on material circulation process changes accompanying the earthquake

(Principal Investigator: Toshi Nagata)

Continuous nutrient supply to the Sanriku coastal region supports phytoplankton growth, which is responsible for the seafood abundance in the area. The earthquake and tsunami produced changes in landforms, causing new patterns of freshwater inflow in coastal areas, as well as alterations in ocean currents. These changes had an impact on the processes of nutrient supply and the food chain structure. Through detailed analysis of this impact, we aim to elucidate mechanisms of maintenance and production of fishery resources.


4. Elucidation of the actual status and impact of land-based pollutant inflows

(Principal Investigator: Hiroshi Ogawa)

The destruction of the town caused by the earthquake and tsunami is predicted to have changed the quantity and quality of various substances that poured into the sea from the land. Furthermore, there is a possibility that some of the buildings and their contents that were swept into the sea may still remain on the bottom or within the sediment of the coastal region and release artificial substances into the water. By using highly sensitive detection technology, we will elucidate the existence, fate and impact of environmental pollutants.


5. Construction of an integrated model combining ecosystem and physical processes

(Principal Investigator: Kiyoshi Tanaka)

Otsuchi Bay is located along the western margin of the North Pacific in an area where the Tsugaru, Oyashio, and Kuroshio currents form a complex mixture of waters. The movement of these currents has a significant impact on the flow dynamics and the mixing process of chemicals, as well as on biological processes. We want to study the movement of these currents and combine the results of this research with biological information by constructing an integrated model of the ecosystem.


6. Analysis of the chemical dynamics in water catchment areas, rivers, estuaries, and coastal waters

(Commissioned by Iwate University, Principal Investigator:
Teruyuki Umita)

Chemicals from the land flow into the coastal waters, which affects not only the primary production of plants, but also a variety of biological processes in the coastal area. By means of basic research of the rivers in the Sanriku area, we will clarify the impact of freshwaters on the coastal ecosystem.

   katagishi river

7. Monitoring and modeling of river water mixing and diffusion in estuaries, brackish waters, and coastal areas  (~2014)

(Commissioned by Tokyo University of Marine Science and Technology, Principal Investigator:
Hidekatsu Yamazaki)

Depending on various factors, such as the quantity of the flow, temperature, and the structure of estuaries and the seabed, the river water gradually mixes with the seawater and flows to the open sea. In order to estimate the dynamics of the chemicals and their contribution to the biological production in the bay, it is important to accurately clarify the mixing and diffusion process. We will elucidate and model physical processes, making full use of the observation equipment originally developed for the project.