Coastal Seagrass In Danger: 58 Percent Of Meadows In Decline

WASHINGTON — Coastal development and declining water quality are threatening seagrasses worldwide, researchers report. A study of coastal grasses around the world shows that 58 percent of the seagrass meadows are in decline, according to a report in Tuesday's edition of Proceedings of the National Academy of Sciences.

Seagrass provides habitat for coastal life and helps reduce the impact of sediment and nutrient pollution.

"The combination of growing urban centers, artificially hardened shorelines and declining natural resources has pushed coastal ecosystems out of balance. Globally, we lose a seagrass meadow the size of a soccer field every thirty minutes," co-author William Dennison of the University of Maryland Center for Environmental Science said in a statement.

"With the loss of each meadow, we also lose the ecosystem services they provide to the fish and shellfish relying on these areas for nursery habitat. The consequences of continuing losses also extend far beyond the areas where seagrasses grow, as they export energy in the form of biomass and animals to other ecosystems including marshes and coral reefs," Robert Orth of the Virginia Institute of Marine Science of the College of William and Mary added.

The researchers said that since 1990 there has been about a 7 percent loss of seagrass per year, with the major impacts coming from coastal development and dredging and reductions in water quality.

The research was supported by the National Center for Ecological Analysis and Synthesis (NCEAS) in Santa Barbara, California, through the National Science Foundation.

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On the Net:

PNAS: http://www.pnas.org

Comments

[RomeoMD25]

06:43 PM on 07/01/2009

# 1. Each year 186 billion tons of CO2 enter the earth's atmosphere. Of that, only 6 billion tons are from human activity (3.2%). Some 90 billion tons come from biologic activity in earth's oceans and the rest from such sources as volcanoes and decaying land plants.
# 2. CO2 is an odorless, colorless, and tasteless gas. The CO2 that goes into the atmosphere does not stay there for long. It is continually recycled by terrestrial plant life and earth's oceans -- the great retirement home for most terrestrial carbon dioxide. The buffering capacity of the oceans is enormous. The oceans currently contain about 50 times as much CO2 as the atmosphere.
# 3. Plants absorb CO2 and emit oxygen as a waste product. Humans and animals both breathe oxygen and emit CO2 as a waste product that helps keep our bodies' pH normal. It works out nice for all those involved.
# 4. CO2 is a nutrient to plants, not a pollutant. Plant-growers introduce more CO2 into their planting sheds when they want to stimulate growth. And all life -- plants and animals alike -- benefit from more of it. All life on earth is carbon-based and CO2 is an essential ingredient.

[elmerfude]

03:15 PM on 07/01/2009

Another environmental nail in our coffin for the illiterate id ots to deny.