Deep-sea plastic trash first full-scale survey August 18 19:59
With ocean pollution from plastic waste becoming a serious problem, the Japan Agency for Marine-Earth Science and Technology has made a full-fledged investigation into the status of deep-sea pollution and its impact on ecosystems for the first time.
In April, the Japan Agency for Marine-Earth Science and Technology launched a new group to study the actual state of marine pollution from plastic waste.
The survey will be carried out for about 3 weeks from the 28th of this month, off the coast of Sagami Bay and off the Boso Peninsula.
Collect sediment from a depth of 1200m to 9200m, measure the amount of microplastic less than 5mm in size and the age at which it is of concern to affect the ecosystem, Check for any plastic.
In addition, the plastics that are sold on the market and special plastics that are decomposed by microorganisms into water, carbon dioxide, etc., are placed on the seabed at a depth of 1200 meters for three years, and experiments are conducted to see how much the plastics are decomposed in the deep sea. about it.
Masafumi Tsuchiya, group leader of the Ocean Plastics Dynamics Research Group, said, “In many cases, we do not know how much plastic waste is spread and how much is collected in the deep sea. I think that it might have reached the Mariana Trench, and that would be a chance to think about the problem of marine pollution. "
Plastic waste is on the coast after the typhoon
On the 16th when Typhoon No. 10 passed, plastic garbage such as plastic bags and plastic bottle lids were launched on Katase Beach in Fujisawa City, Kanagawa Prefecture.
A man in his thirties in Okayama Prefecture who was visiting the coast said, “I feel sorry because I hear that birds will get tangled in plastic waste or eat garbage and die.”
Also, a teenage woman from Kyoto Prefecture said, “I'm careful to throw it in the trash, but I think everyone will clean the ocean if that happens.”
Current state of marine pollution from plastic waste.
Marine pollution from plastic waste has become a global issue.
Once plastic waste flows into the sea, it is difficult to collect, and whales may be swallowed with food and die, which affects the ecosystem.
In addition, while floating in the sea for a long time, it is shattered under the influence of wave power and ultraviolet rays, and becomes a “micro plastic” with a size of 5 mm or less. It has been confirmed that it would enter the body of a living creature.
At the G20 Osaka Summit in June, it was agreed that marine pollution from plastic waste became a major agenda and that measures would be taken globally.
Marine pollution from plastic waste is being investigated and researched in various countries, but the actual situation in the deep sea is unknown.
The Japan Agency for Marine-Earth Science and Technology has been conducting various surveys in the deep sea until now, but after checking the images and images taken during the survey since 1982, it was found that a lot of plastic garbage was reflected.
In order to get to know the current state of the deep sea, we have made a database of garbage videos available on the Internet for two years.
Of these, a picture taken in May 1985 of Sagami Bay near a depth of 1100 meters shows that plastic bags are scattered.
Also, in the vicinity of about 500 meters deep off the coast of Otsuchi, Iwate, taken in May 2012, you can see that the sea anemone hides something like a plastic bag.
On the other hand, in May, an American seabed explorer witnessed contamination by plastic bags, etc. when he first succeeded in the world's first diving at a depth of 10,927 meters in the Mariana Trench in the Pacific Ocean. There is interest in deep-sea plastic pollution.
Sea area to investigate
UNEP = According to the United Nations Environment Program, plastic waste that has flowed into the sea is likely to gather at specific locations due to the effects of ocean currents and winds.
Of these, the place close to Japan is called the “Pacific Garbage Belt”. In this survey, Sagami Bay faces Tokyo, Kanagawa Prefecture, etc., where population is large, economic activity is high, and waste is expected to be large. We investigate off the Boso Peninsula and the surrounding waters around the Izu Islands.
This means that there is a possibility that a lot of plastic waste is collected in the deep sea due to the influence of the ocean currents, not only from Japan but also from other Asian countries.
Focus on micro plastic
In this survey, we will examine in detail the small plastic waste called “micro plastic”.
Microplastics are plastics that are finely crushed to a size of 5 mm or less by the force of waves or ultraviolet rays. They are easy to attach harmful substances and are easy to swallow fish. It is.
The survey uses a manned diving research ship "Shinkai 6500" to collect sediment from the seabed at a depth of 1200 to 6000 meters and measure the amount and type of microplastic contained in it and the age at which it was deposited. In addition, we will directly collect seabed organisms and microplastics with a tubular device.
In addition, we can collect organisms in addition to sediments by using an unmanned device even at a depth of 9200 meters, which cannot be reached with Shinkai 6500, and check for microplastic in the stomach.
Furthermore, we will conduct experiments to see how much plastic is decomposed in the deep sea where ultraviolet rays do not reach and water temperature is low and water pressure is high.
Put a plastic that is generally sold in small cylindrical containers with holes to allow seawater and plankton to enter and exit, and a special plastic called `` biodegradable '' that decomposes into water and carbon dioxide by microorganisms. This means that it will be placed on the seabed at a depth of 1200 meters off Hatsushima in Shizuoka Prefecture for 3 years.
In addition to this, the net that is 1 meter and 75 centimeters in length is connected to the ship and pulled to collect the microplastic on the sea surface of the survey point, so that the waste accumulates due to the difference in the types and amount of garbage in the deep sea and the sea surface. I will guess the process.