14.3 Ocean Organic Resources Development
The operation of the demonstrative unit of the density current generator was started by Marino Forum 21 in Gokasho Bay of Mie Prefecture. The unit pumps up the bottom water which is poor in oxygen concentration, eutrophic and low in temperature by an electric impeller, and mixes it with the surface layer water which is high in oxygen concentration and high in temperature to diffuse the mixed water which is appropriately eutrophic and appropriate in oxygen concentration far away to improve the water quality in an extensive range. Because the mixed water (density current) of the medium density is naturally diffused between the surface layer water and the bottom water, the small power is also characteristic. Various methods of utilization of the deep water will be proposed in future.
14.4 Ocean Space Utilization
The second-term research on the super-large floating marine structure (Mega Float) was started. The research is achieved for three years from 1998 to 2000, aiming at the verification of the functions requested for the application of the airport through the demonstrative test. Thus, the air port model of 1000m in length and 60m in width, which is larger than that in the first term, will be constructed by the fall of this year, and the demonstrative test such as the landing/taking-off of aircrafts will be actually carried out making use of this model, and further, the simulation program will be developed.
The construction results by private companies include the break water, the floating pier, and the fishery reef.
14.5 Ocean Observation
A large survey ship “SHOYO” owned by the Maritime Safety Agency was constructed by Mitsui Engineering & Shipbuilding. The ship is equipped with the high-tech equipment including the sonars which are available among 8 ones in the world and capable of precisely observing the fluctuated geography due to the landslide and the fault of the deep sea bottom, and the ship is expected to contribute to the survey and research of the precise oceanographic geology.
The research on the deep-sea drilling technology development (OD21 Project) has been promoted under the leadership of the Science and Technology Agency and the Japan Marine Science and Technology Center. This is because many needs for the scientific drilling are distributed over the waters of at least 2500m in water depth, and the large depth drilling technology is expected under the International Deep-sea Drilling Plan (ODP). Contribution to the study of the global fluctuation and the search of the undersea life and resources (gas hydrate, etc.) is expected.
[Takaaki MIZOKOSHI]
