白化现象对珊瑚有长期不良影响

A new study by a Florida State University biologist shows that bleaching events brought on by rising sea temperatures are having a detrimental long-term impact on coral. Professor Don Levitan, chair of the Department of Biological Science, writes in the latest issue of Marine Ecology Progress Series that bleaching -- a process where high water temperatures or UV light stresses the coral to the point where it loses its symbiotic algal partner that provides the coral with color -- is also affecting the long-term fertility of the coral.

"Even corals that didn't bleach aren't reproducing at the levels they should," Levitan said.

Most corals reproduce by releasing sperm and eggs into the ocean during brief annual spawning events. The chance of sperm finding and fertilizing an egg depends on corals spawning in close proximity and in synchrony with each other.

In a study of the corals that build the major framework of Caribbean coral reefs, Levitan's team found that the species living in shallower water experienced near total reproductive failure, while the species living in deeper water was about half as likely to spawn.

"The remarkable finding from this study was that the reduction in spawning persisted for three additional years, long after the corals had regained their symbiotic partners and regained their normal appearance," Levitan said.