FUKUSHIMA--With the help of generous prefectures, Fukushima Prefecture is starting a nine-year plan to restore disaster-prevention coastal forests along a 145-kilometer stretch of the 185-km tsunami-inundated coastline.
The prefecture will plant 4.6 million seedlings in an area covering about 460 hectares, or about 700,000 seedlings annually for seven years, starting in fiscal 2014, according to a report on the plan.
The prefecture will start collecting seeds from pine cones this fiscal year that will grow into seedlings in two years. The first of a planned pine forests will be erected on a 30- to 40-km stretch.
Coastal forests in six prefectures, from Aomori Prefecture to Chiba Prefecture, were swamped by the tsunami triggered by the Great East Japan Earthquake on March 11, 2011.
In Fukushima Prefecture, 295 hectares of forests were inundated and 70 percent were destroyed. The trees that survived now face death because of the salt left in the ground by the seawater.
Some of the forests did their job in preventing the disaster from becoming worse in certain areas.
The rich pine forest on Matsukawaura beach in Soma, Fukushima Prefecture, functioned as a breakwater, weakening the tsunami and blocking debris from flowing into the inland area. The forest, however, was wiped out.
In Iwaki, Fukushima Prefecture, the tsunami reached the top of the first floor of a hospital building about 100 meters from the coast.
But the thick pine forest about 100 to 200 meters wide along the 10-km-long Shin-Maikohama beach weakened the tsunami and stopped the waters around rice fields near a community 500 meters from shore.
“Without the pine forest, our community would have been destroyed,” said a 70-year-old woman who farms in the area. “I am grateful to our ancestors (who raised the forest).”
The history of coastal disaster-prevention forests in Fukushima Prefecture dates back to the Edo Period (1603-1867).
The forest on Shin-Maikohama beach is believed to have been built by the Iwakitaira clan, while the Matsukawaura pine forest was created by the Soma Nakamura clan.
In Hachinohe, Aomori Prefecture, a coastal forest stopped more than 20 ships and the tsunami waves from reaching residential areas.
The standard width of the new forests in Fukushima Prefecture will be widened from the conventional 50 meters to 200 meters. The Forestry Agency said in a report in February that a 200-meter-wide disaster-prevention forest can weaken the strength of a tsunami by 30 percent.
Embankments will be built to keep the trees deep-rooted. However, the forests within a 20-km radius of the crippled Fukushima No. 1 nuclear power plant will be excluded from the plan.
Fukushima Prefecture possessed enough pine seeds for only 180,000 trees a year, so it sought help from other prefectures. Ibaraki, Tochigi, Kanagawa, Ishikawa, Shiga, Yamaguchi and Ehime prefectures agreed to supply seeds for 650,000 trees.
Half of those will come from Shiga Prefecture.
Shiga Governor Yukiko Kada met with Fukushima Governor Yuhei Sato on April 18 and handed over pine seeds, saying, “Please restore the coastlines of white sand and green pines.”
Miyagi Prefecture can self-supply seeds for 3.5 million seedlings in 10 years, and is considering seeking outside support for 4 million more seedlings.
Iwate Prefecture has secured seeds to build forests on 45 hectares that are deemed priority areas for disaster prevention.
However, it will take time to come up with a restoration plan in Iwate Prefecture. Some forests, including Takatamatsubara, known for the miracle tree that survived the tsunami, have sunk below ground level.
This article was written by Yoshinori Hayashi and Takemichi Nishibori.
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