Featured Research

from universities, journals, and other organizations

Invasion Of New Beach Grass Could Weaken Shoreline Protection

Date:
September 26, 2007
Source:
Oregon State University
Summary:
An invasion of American beach grass is under way along the Oregon coast, threatening to change dune ecology and reduce the ability of dunes to protect roads, property and towns from coastal storms. Scientists have documented a slow but steady takeover by this beach grass, an invasive species. They found that protective "foredunes" covered by the new grass species are only about half as high as those created by the European species of grass that were formerly dominant.

A housing development behind a foredune created by European beach grass at Pacific City, Ore.
Credit: Image courtesy of Oregon State University

An invasion of American beach grass is under way along the Oregon coast, threatening to change dune ecology and reduce the ability of dunes to protect roads, property and towns from coastal storms.

Related Articles


Scientists at Oregon State University have documented a slow but steady takeover by this beach grass, an invasive species. They found that protective “foredunes” covered by the new grass species are only about half as high as those created by the European species of grass that were formerly dominant.

This phenomenon has already occurred from Long Beach, Wash., to Pacific City, Ore., and is continuing to spread, the researchers say.

“This decrease in dune height may translate into a significant decrease in coastal protection from storms and tsunamis,” said Eric Seabloom, an OSU assistant professor of zoology.

In continuing studies, scientists plan to use oceanographic models to show just how much protection is lost when European beach grass is replaced by American beach grass.

The European grass – also an invasive species – has been dominant since it was first introduced to the area around the turn of the 20th century, to help stabilize blowing sand on the coast.

“It did its job extremely well,” said Sally Hacker, an OSU associate professor of zoology and expert on marine and estuarine communities. “Without it, the sand would cover towns and roads.”

The European beach grass did so well that by the 1930s it had spread along the entire Oregon coast, and created an extensive “foredune” system, large protective sand hills found in front of almost every sandy beach in Oregon. These dunes can provide significant protection for homes, roads, towns and other infrastructure, and serve as a barrier against flooding during major storm surges and perhaps even tsunamis.

But the second invasion by the American beach grass species had gone practically undetected. Introduced near the mouth of the Columbia River in the mid-1930s, also to stabilize beaches, American beach grass tends to out-compete its European cousin. The status of this beach grass variety went unnoticed for more than 50 years, until Seabloom and a colleague discovered it had crept as far south as Tillamook Head and as far north as the Olympic Peninsula.

Surveys of the entire Oregon coast have determined that the current range of domination of American beach grass extends from Long Beach, Wash., to Pacific City, Ore. But even beyond that, from Pacific City south, most of the beach grass is the American beach grass, with just a few pockets of European beach grass.

“Lower dune heights, increasing wave heights that have been observed over the last 50 years, and global climate change could create a scenario in which the dunes no longer serve a coastal protection function,” Hacker said.

Beyond the protection concerns, there are other ecological issues in play as well.

While the foredune system created by European beach grass is good for coastal landowners, it is not so good for endangered beach plant species and the federally-threatened Western snowy plover, scientists say. As more sand accumulates in growing stands of beach grass, the land behind the dune tends to get “terrestrialized,” or turned into wetlands and forest habitats.

“The willows and other trees and larger shrubs you often see behind the dunes are an indication that wetlands are being formed in the mini-valley behind the dunes,” Hacker said.

As that process advances, beach habitat disappears, taking with it the plovers’ critical nesting grounds. The southward march of the American beach grass species could reverse the terrestrialization trend, as the American variety creates a much smaller foredune.

Hacker and Seabloom have received funding from Oregon Sea Grant to study the impacts and interactions of these invasive grasses on the Oregon coast. They are also working with Peter Ruggiero, a geomorphologist in the Department of Geosciences at OSU, to understand the coastal protection capabilities of dunes along the coast.


Story Source:

The above story is based on materials provided by Oregon State University. Note: Materials may be edited for content and length.


Cite This Page:

Oregon State University. "Invasion Of New Beach Grass Could Weaken Shoreline Protection." ScienceDaily. ScienceDaily, 26 September 2007. <www.sciencedaily.com/releases/2007/09/070923203558.htm>.
Oregon State University. (2007, September 26). Invasion Of New Beach Grass Could Weaken Shoreline Protection. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2007/09/070923203558.htm
Oregon State University. "Invasion Of New Beach Grass Could Weaken Shoreline Protection." ScienceDaily. www.sciencedaily.com/releases/2007/09/070923203558.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
New Fish Species Discovered, Setting Record for World's Deepest

New Fish Species Discovered, Setting Record for World's Deepest

Buzz60 (Dec. 22, 2014) A new species of fish is discovered living five miles beneath the ocean surface, making it the deepest living fish on earth. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins