Izumi Washitani is not only a professor of conservation ecology at the top-flight University of Tokyo, she’s also a committed activist who applies her studies to restoring threatened biodiversity.
One of the threatened species she has researched is the so-called floating-heart plant (Nymphoides peltata) in Kasumigaura, Japan’s second-biggest lake, which straddles Ibaraki and Chiba prefectures.
Washitani, 57, and her fellow scientists have monitored the plant for the Red Data Book compiled by the Environment Ministry. What they found, among many other things, was that in 1996 it covered some 99,497 sq. meters in the lake — but by 2000 it was down to 10,081 sq. meters.
Floating heart plants suffered such a calamitous decline, the researchers found, mainly because of bank- protection engineering projects carried out around the lake in 1995 by the construction ministry.
“When the banks were concreted, plants like the floating heart that used to thrive there before lost their natural habitat,” Washitani said.
To restore the species, a local citizens’ group set up a project and Washitani has supported the initiative. As the plant needs to be in contact with water when it puts forth buds, she suggested reconstructing the angle of the lake’s banks to restore them to how they were by dredging up earth from the bottom of the lake.
“The earth from the lake bottom contains living seeds of floating hearts and other endangered plants,” Washitani said, explaining that she regards such earth as a “soil seed bank.”
“The seeds can revive the ecology that used to exist,” she says with an excited twinkle in her eye.
The project was carried out with the cooperation of the citizens’ group, Washitani and other researchers and authorities.
As a result, floating hearts revived to cover 21,204 sq. meters in the lake by 2006.
“Restoring diverse and suitable plants for an area is the most important task when we try to restore an ecosystem,” she said.
Washitani’s passion for nature goes back to her childhood, when she spent vacations in the countryside outside Tokyo, where she lived, and found many plants there that enriched her young life.
But for Washitani, the road to becoming a professional botanist was not entirely smooth. After earning her Ph.D. in botany at the University of Tokyo in 1978, she at first found it very difficult to get a job. Back then, as she recalls, universities and companies did not provide equal job opportunities for women and men.
“I thought that if I couldn’t find a good job, I should study what I really wanted to,” she said.
As a postgraduate student who had to pay her own research expenses, Washitani studied the evolution of various plants, while also working at cram schools and raising two daughters. Then, at age 36, she got her first job as a lecturer at the University of Tsukuba in Ibaraki Prefecture.
There, as she delved deeper into plant ecology, it wasn’t long before she realized that many, many species were being threatened by development.
“All the plants that I am interested in are dying out. I don’t want wonderful nature to disappear,” she said — adding that this situation drove her to focus on conservation ecology.
“Unless we preserve biodiversity, we cannot secure sustainability for human life,” Washitani stressed.