Researchers at the Graduate School of Tohoku University conducted an annual survey of the ecosystems of the tidal flats scattered across Sendai Island, which were greatly affected by the tsunami following the Great East Japan Earthquake. I confirmed that it had returned to its original form.The survey was carried out with the cooperation of citizen volunteers and a research team formed by the National Institute for Environmental Studies and high school teachers in Miyagi Prefecture.
The magnitude 2011 Great East Japan Earthquake that occurred on March 3, 11 caused a huge tsunami, which caused major changes not only to the townscape but also to the coastal ecosystem.Many of the tidal flats that dot Sendai Island have been documented for the drastic decline of inhabiting species and the emergence of previously unknown organisms.However, it was not known how the biological community would change after such a large natural event.
Therefore, with the cooperation of a total of 500 citizen volunteers, the research team conducted a biodiversity survey on the coast of Sendai over a period of about 10 years.Eight tidal flats in Sendai, including the Gamo Tidal Flat, whose biota was known before the earthquake, Torinoumi, Matsukawaura, and Matsushima Sokanzan.
As a result, in the two to three years immediately after the earthquake, the biota of each tidal flat changed year by year, but as the environment around the tidal flat returned to its original state, species that lived before the earthquake began to be confirmed. After 2 to 3 years, most of the tidal flats returned to their pre-earthquake and indistinguishable biological communities.However, before the earthquake, reeds thrived in the depths of the Gamo tidal flat, and a unique community of organisms was observed.
The results of this survey revealed that the biological community of the tidal flats along the Tohoku coast is an ecosystem with high resilience that can recover from ecosystem disturbances caused by tsunamis in about 10 years if the surrounding environment does not change. and
Paper information:[Limnology Oceanography Letters] Recovery of macrobenthic communities in tidal flats following the GreatEast Japan Earthquake