Loss of Ocean Seagrass Beds Accelerating Due to Human Activity

Saturday, November 14, 2009 by: David Gutierrez, staff writer
Tags: oceans, seagrass, health news

(NaturalNews) As critical for ocean life as coral reefs but less well known, seagrass beds around the planet are also in sharp decline, according to a study conducted by researchers from Australia, Spain and the United States, and published in the Proceedings of the National Academy of Sciences.

"Seagrass beds are at least as economically and ecologically important as tropical forests or coral reefs," said co-author James Fourqurean of Florida International University.

Seagrass meadows provide important habitat and nurseries for large numbers of shellfish and fish, which in turn draws larger marine life to these areas to feed. They also help prevent coastal erosion by stabilizing sediments on the ocean bottom, and filter out many of the wastes that flow into the ocean from the land.

Yet according to the study, the rate of annual seagrass decline has leaped from 1 percent per year before 1940 to 7 percent per year today. An estimated 58 percent of all seagrass meadows around the world are currently in a state of decline. Since 1879, a full 29 percent, or 19,690 square miles, of the meadows have disappeared.

"Globally, we lose a seagrass meadow the size of a soccer field every thirty minutes," said co-author William Dennison of the University of Maryland.

Development has been the primary driving force behind sea grass destruction. Forty-five percent of the world's population lives along the coast, and the industrial revolution led directly to sea grass declines in North America and Europe due to water pollution and outright dredging of sea grass meadows. The major areas of sea grass decline are now along coasts of the Pacific and Indian oceans.

"Seagrasses are disappearing because they live in the same kind of environments that attract people," Fourqurean said. "They live in shallow areas protected from large storm waves, and they are especially prevalent in bays and around river mouths."

Global warming is expected to exacerbate sea grass decline due to ocean warming and rising sea levels.

Sources for this story include: www.reuters.com.