<< Research into artificial sea mountains is becoming increasingly important >>
<< World population and food >>
The world’s population, which was around 2.5 billion in 1950, has increased 3.2 times to around 8.2 billion in 2025, 75 years later. It is still increasing by 77 million people per year at a rate of 1.2%. By 2050, the world’s population is expected to reach 9.3 billion according to the United Nations’ medium-term estimates. In this situation, improving food self-sufficiency is a major issue for most countries in the world. Agricultural technology, which gave birth to many ancient civilizations, has created environments suitable for growing crops by utilizing sunlight, water, and fertilizer. Even now, breeding is being carried out using biotechnology, however, the fear that land-based production alone will not be able to support the world’s population is growing year by year.
<< Food production in oceans >>
Food production in oceans, which cover 70% of the earth’s surface, has long been a dream for humanity, and it has been very difficult to fully realize. In addition, it is said that the world’s fishing industry is facing a crisis of destruction due to the increase in fish consumption worldwide due to the current health and safety orientation, overfishing, and marine pollution (Figure: Science. Vol. 314). In relation to such a major issue, Japan’s First Basic Plan for Ocean Policy, which was approved by the Cabinet in March 2008, states that basic production will be increased in offshore areas that have not been used by humans until now. We have a responsibility to comply with the Basic Act for Ocean Policy while giving due consideration to the environment.
<< Food Production and Photosynthesis >>
The origin of biological production is photosynthesis, which is carried out by almost all phytoplankton and algae in the ocean as well as on land. Unlike agriculture, photosynthesis in the ocean is not limited by water or temperature, but is limited by the concentration of nutrient salts in the euphotic zone. When seawater from the euphotic zone downwards, which is rich in nutrient salts, is mixed into the euphotic zone by wind or tidal energy, biological production begins. The Fisheries Agency focused on the principle of how good fishing grounds are formed around reefs and shoals, and conducted a demonstration project to increase the amount of phytoplankton by building artificial mountain ranges on the continental shelf for the first time in the world. This project was conducted for six years from 1995, and achieved remarkable results, including a significant increase in the amount of phytoplankton and the amount of fish caught.
<< Utilization of Exclusive Economic Zone >>
Japan’s exclusive economic zone is the sixth largest in the world. If we can produce food, especially seafood, which is high-quality protein, in this area, we can improve our food self-sufficiency rate. The artificial sea mountains project is an innovative technology that artificially creates natural reefs that have been used by fishermen for generations, and uses natural currents to supply the nutrient layer with nutrients, thereby stimulating the photosynthesis of phytoplankton and increasing food production.
This project is also about providing a source of protein for Japan’s population of 130 million people, using the country’s own seas. Once completed, the artificial sea mountains will create an environment that uses no artificial energy at all, and instead uses natural forces to increase the amount of phytoplankton.
<< A society in harmony with nature and a recycling-oriented society >> The artificial sea mountains range is an important infrastructure development project that is being implemented to produce food in the ocean. In the vast ocean, it may be a project the size of a needle, but tens of thousands of cubic meters of material are used in each project. Where is it best to procure this material as a public works project? In the artificial submarine mountain range projects that have been carried out so far, two types of material have been used. One is hardened blocks made from recycled coal ash, which were used in the first three projects. The other was made from valuable natural stone quarried from mountain forests, and was used in five projects. Time will tell which is more compatible with nature and in line with the spirit of the Basic Law for Establishing a Recycling-based Society. It will also be verified that the sea mountains made up of large blocks of stone allow a greater variety of fish and shellfish to live together, and that they form rich reef ecosystems.
We would be happy if we could realize humanity’s dreams by sharing the results of our observations, catches and analysis with everyone on the world.