The world has moved on since that 1986 catastrophe, but at Chernobyl, one thing hasn't changed very much: The dead trees, plants and leaves at the contaminated site don't decay at nearly the same rate as plants elsewhere, researchers have found.

"We were stepping over all these dead trees on the ground that had been killed by the initial blast," Tim Mousseau, a professor of biology at the University of South Carolina, said in a statement. "Years later, these tree trunks were in pretty good shape. If a tree had fallen in my backyard, it would be sawdust in 10 years or so." [Images: Chernobyl, Frozen in Time]

Mousseau and Anders Møller of the Université Paris-Sud have made ongoing investigations into the biology of radioactive areas like Chernobyl and Fukushima, Japan.