Reconstruction work Remaining tidal flat reclamation canceled Iwate Rikuzentakata Hirota Bay September 18, 18:59

Despite being damaged by the tsunami caused by the Great East Japan Earthquake, a rich ecosystem has been formed since then, and it is valuable due to the reclamation of residual soil by the city on the tidal flats of Rikuzentakata City, Iwate Prefecture, which has been selected as an important wetland by the Ministry of the Environment. A group of experts has requested that the landfill be suspended and that the method of treating the tidal flats be reconsidered, as the ecosystem may be lost.

The reclamation work is being carried out on a tidal flat called "Otomoura" in Hirota Bay, Rikuzentakata City, Iwate Prefecture, which is known for "Miracle Pine".

After the place that was a tidal flat was reclaimed in the 1965's, the embankment collapsed due to the tsunami of the Great East Japan Earthquake and it became a tidal flat again, and rare species of shellfish etc. have been confirmed, and in 2016 the environment It has also been selected as an "important wetland" in the province.

Since late last month, Rikuzentakata City has been working on this tidal flat to reclaim 54,000 cubic meters of residual soil generated by the earthquake reconstruction work.

According to the city, the landfill site is planned to be sloped and covered with sand to regenerate the tidal flats in the future.

The Natural Environment Conservation Committee of the Benthos Society of Japan, which is made up of experts in benthic organisms, said that the current method of landfilling with surplus soil would result in the loss of the existing tidal flat ecosystem. We decided to review and submit a request to the city to protect the tidal flats and creatures.

MatsuMasashi Masatoshi professor of Iwate Medical University, which has conducted a survey in local place kind of "biological is large already been reclaimed, the history of the creatures of the 10 years after the earthquake. Had been returned to the white paper

becomes yuan as expected I don't know if it is, and if it does, I should reconsider the future design after understanding that it will take time. In the

reconstruction work, there are cases where the important natural environment is lost, so I would like you to include the perspective of biodiversity. I point out.

In response, Yasuhiro Sugano, chief of the Fisheries Division of Rikuzentakata City, said, "In response to the opinions of the residents that the tidal flats should be regenerated, the city intends to carry out the construction while giving consideration to living things. Since there are some indications, I would like to proceed with the construction while listening to the opinions of experts as far as I can. "

Expert "I want you to recognize the value of highly diverse tidal flats"

At Otomoura, research groups such as Iwate Medical University, Tohoku University, and the National Institute for Environmental Studies have conducted a survey on changes in the environment after the earthquake as part of a survey by the Ministry of the Environment.

As a result, there were 49 species of organisms living in the tidal flats such as crabs and shellfish in 2013, 56 species in 2014, 60 species in 2015 and 2016, and in 2017. It was found that 84 species and 88 species were increasing year by year in 2018, and 161 species have been confirmed so far.

In addition to the mantis shrimp that inhabits only Otomoura in Iwate Prefecture, which is called "Balsanajako", shellfish such as "Unenashitomayagai" and "Onogai", which are designated as near-threatened species in the Red Data Book of the Ministry of the Environment, etc. The inhabitation of a wide variety of creatures was confirmed.

Professor Masatoshi Matsumasa of Iwate Medical University, who has conducted the survey, said, "There are no large tidal flats in the Sanriku region, and while construction of seawalls is underway, the remaining areas are extremely valuable, especially Otomoura, which is not large but ecological. The diversity of the system was high, and it had a positive effect on the surrounding environment. I want you to recognize the value of such tidal flats. "