Scott

October 26, 2010 | General

Employing Marsh Grass And Compost To Heal The Gulf


BioCycle October 2010, Vol. 51, No. 10, p. 24
Gulf Saver Bags designed to stabilize eroding marshlands give young restoration plants a good start and place hydrocarbon-eating microbes at the ready.
Dan Sullivan

LONG before back-to-back hurricanes Katrina and Rita or the massive BP oil spill assaulted the Gulf Coast, the area’s fragile ecosystem had been ravaged by progress. Unfortunately, says one local organization dedicated to marshland rehabilitation, that damage over time impaired the area’s natural defenses against such onslaughts.
“A century of neglect of this coastline has led to the loss of 2,300 square miles of landmass,” says Natalie Snider, science director and restoration ecologist for the nonprofit Coalition to Restore Coastal Louisiana (CRCL), based in Baton Rouge. “Typically we’re losing 25 to 35 square miles a year. With Katrina and Rita, we lost over 200 square miles over a two-day period because of these two events. Another large chunk will be lost to the BP oil spill. As long as we are vulnerable and not doing the full-scale remediation that’s needed, the coastline remains under multiple threats.” According to a National Wildlife Federation bulletin, oil can kill or reduce growth of marsh grasses, a key source of food and cover for wildlife. “This vegetation loss will also lead to erosion and contribute to the coast’s already rapid rate of land loss,” notes the bulletin.
The nonprofit CRCL has been leading grassroots restoration in the area for more than 20 years, with big-picture goals that include reintroducing the sediments and fresh water required of wetlands ecosystems now being flushed into the Gulf and over the continental shelf due largely to manmade levees constructed to prevent flooding of the Mississippi River. In addition to damage caused by the levees and navigation channels in the Mississippi, channels dug for oil and gas exploration in the Gulf throughout the 1960s and 1970s have allowed for the intrusion of salt water into these same estuaries, decreasing the productivity of bank-stabilizing vegetation.
While coastal Louisiana’s man-induced challenges began at least a century ago, Katrina, Rita and BP have all brought unprecedented attention to the region. “The Coalition has run a community based coastal restoration program for over 10 years now,” explains Snider. “We have several restoration projects on the ground with volunteers from the community and elsewhere. After the oil spill, we had nearly 30,000 people sign up to volunteer. One of our objectives is to engage people in this issue of coastal land loss and get them in touch with and out into the marshes and swamplands. We’ve done seven projects since the spill and have two more planned. We’ll be planting 70,000 grasses … on the north shore of Lake Ponchartrain.”
Educating the public about historic degradation along the Gulf Coast, its causes, potential solutions and ongoing consequences has remained a core theme of CRCL’s work. While all those channels and levees help supply the nation with goods and services, Snider says, “they also degrade and erode the marsh. If we had restored some of the marshes, the BP oil spill wouldn’t have had the same effect that it did, and the hurricanes definitely would not have. We have to reconnect the Mississippi River back to the wetlands, which are starved for sediment and fresh water.”
Freshwater or sediment diversions – creating passageways that would allow for the delivery of river water and sediments that are a natural part of coastal estuaries without impinging on the levees’ structural integrity or functionality – could actually help nature fight back when an event such as the BP oil spill occurs, suggests Snider. “There was a large area of the delta where there was oil and where there was no oil,” she says, explaining that where there was a balanced, healthy ecosystem – versus saltwater intrusion – the fresh water appeared to “push the oil out.”

SOWING THE FUTURE

Short of a major civil engineering undertaking to rebalance the ecosystem, the CRCL is doing what it can to curtail the loss of coastal marshlands. CRCL teamed up to launch the Gulf Saver campaign with RMP Ecosystems (a New York-based native plant nursery specializing in fast-growing trees for restoration and conservation), Restore the Earth Foundation (a nonprofit set up to administer and campaign for the project), Trident Environmental Services (a compost consultant), Barataria —Terrebonne National Estuary Program, Audubon, The Nature Conservancy and others. At the root of the campaign, designed to tap into the massive desire to volunteer in the wake of the BP oil spill, is the Gulf Saver Bag. The campaign’s website (gulfsaversolutions.com) describes the bag as: “a package of native marsh grasses with its own supply of totally natural nutrients and billions of oil eating microorganisms to support, feed and protect the marsh grasses, promoting survival and growth, restoring the ecosystems and habitats.” The idea is to have volunteers in shallow draft boats place the biodegradable planted burlap bags at the edge of the eroding marshes, to stabilize the banks and introduce enough nutrients in the sediment-challenged environment to root the marsh grasses, which will do their own bank stabilizing and sediment building as they mature and the burlap sacks decay.
While the efficacy of compost to clean up hydrocarbons has been well-documented (see “Oil and Compost Could Prove a Good Mix in the Gulf,” May 2010), the CRCL makes it clear that any such benefits remain tangential to preventing more land loss. CRCL officials also say they are unconcerned with suggestions from skeptics that the bags will wash away before the young native marsh grasses establish.
“The coalition is viewing this not as a remediation strategy but to stabilize the shoreline,” says CRCL’s Snider. “The idea is that the bags will root in before they are swept away by wave energy. There are secondary benefits with the [enhanced] microbial community, but that is not our main focus at this point. The bags weigh 25 pounds each, will become waterlogged and will be self-anchoring. For the most part they would stabilize themselves.”
Adds CRCL executive director Steven Peyronnin, “Our goal is not to place these bags in an oiled environment. We’re planting new vegetation to offset some of the damage that’s already been done and, should some of the oil ever find its way into these marshes, we are enhancing the system’s ability to respond via natural organic processes.”
He explains that the areas identified for bag deployment are inland marshes that don’t see significant wave energy. “They are shallow bays fairly removed from the open Gulf,” Peryonin says. “These areas have suffered land loss, but they are not exposed to high winds, high wave action or tides.” Additionally, he says, the bags will be placed in such a manner that they will maintain linear integrity.
These inland marshes – typically a mixture of fresh and brackish water – offer critical habitat, he adds. “It’s an abundant area for fisheries – it’s a critical area that allows a place for development from juveniles into maturity.”

WAITING FOR A PERMIT

For all the wannabe volunteer power and partnership clout the Gulf Saver program has lined up, the waters still need to be tested, so to speak. Other challenges remain as well.
Funds for full deployment – some of which could come from BP – fall well short of the 880,000 bags the partners hope to deploy, and boats and volunteers are sidelined until a 404 wetlands permit is approved by the U.S. Army Corps of Engineers and a green light given by the Louisiana Department of Natural Resources. “Since we’re adding sediment, we need the permits,” says Jeremy Henley, a CRCL staff member who has been leading the charge for the organization and is a student in the Coastal Restoration Science program at the University of New Orleans.
Another reason the project has forestalled is concern about the tropical storm season. “One could come in and completely wipe out our efforts,” Henley says, adding that by the time hurricane season passes he hopes the Corps will have issued a blanket permit for the restoration work and not require a separate procedure for each project moving forward.
“The microbes being introduced are native and natural to the environment,” he explains, one of them [pseudomonas putida] perhaps having evolved to eat hydrocarbons that are both human introduced and which naturally seep through the ocean floor. “In un-oiled areas they lie dormant,” Henley says. “As soon as hydrocarbons are introduced, they thrive. Then they start to die back and become food for zooplankton and phytoplankton … so it’s a full cycle. The microbes also work in concert with each other,” he says. “One digests hydrocarbon; another feeds off of decaying plant matter and nutrients and adds oxygen. The microbe that digests oil uses that oxygen added to the system and breaks down the oil into water and carbon dioxide.”
So far CRCL has identified three sites for deployment. The pilot site is west of Empire, Louisiana, on the Mississippi River delta on land owned by Conoco-Phillips, Inc. “They own the marsh where the product is going to be placed,” says Henley, adding that the site encompasses about 4 linear miles of marsh edge and 10 square miles of marshland. Conoco-Phillips also owns the marina that will serve as the staging area for the first full-scale Gulf Saver Bag project. The company has pledged the use of vessels to monitor the project in terms of growth, survivability and establishment plants, and their ability to handle any introduced oil, but to date has offered no financial support, he adds. “They might come out see what we’re doing, but they’re not involved in planning or placement. We have their full permission to use any of their land – they’re one of the largest landowners in south Louisiana.”


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