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General
RESTORATION OF MARSH VEGETATION IMPACTED BY THE AMOCO CADIZ OIL
SPILL AND SUBSEQUENT CLEANUP OPERATIONS AT ILE GRANDE, FRANCE
Ernest D. Seneca and Stephen W. Broome'
INTRODUCTION
Tidal salt marshes functon to stabilize estuarine shorelines, to
exchange nutrients with sediments and the surrounding waters, to
provide energy as detrital material to the estuarine food web, and to
serve as nursery grounds for many commercially important fish and
shellfish. Because competing land uses have resulted in a decrease in
areal extent of these valuable resources in the past, there have been
concerted efforts recently to preserve the remaining marshlands and to
reestablish marshes at selected sites. Techniques and procedures have
been developed to: (1) reestablish marsh in areas where Man has
destroyed natural marsh, (2) reestablish marsh along shorelines where
storms have damaged or destroyed natural marsh, (3) establish marsh
along canal banks and shorelines to stabilize the substrate and retard
erosion, and (4) establish marsh on dredged material (Woodhouse et al.,
1974; Garbisch et al., 1975; Seneca et al., 1976).
Our research efforts in marsh establishment along the southeastern
coast of the United States led us to respond to an invitation from the
joint scientific commission of the National Oceanic and Atmospheric
Administration (NOAA)/Centre National pour l'Exploration des Oceans to
study the effects of the Amoco Cadiz oil spill. We developed a
proposal for restoring marsh at the lie Grande site adapting techniques
and procedures developed for Spartina alternif lora Loisel. in North
Carolina (Woodhouse et al . , 1974; Seneca et al., 1976) to restoration
of a part of the lie Grande marsh using vegetation indigenous to that
region. This interim report contains results from 2 years' marsh
rehabilitation research at lie Grande and a nearby estuary at Kerlavos.
Literature Review
The effects of oil pollution on salt marsh vegetation have been
studied and reported by European researchers. Based on observations of
Welsh salt marshes affected by oil spills from the Chryssi P.
Goulandris in January 1967 and the Torrey Canyon in March 1967, Cowell
(1969) rated susceptibility of marsh plants to crude oil and concluded
that salt marshes dominated by Spartina townsendii H. and J. Groves and
Puccinellia maritima (Huds.) Pari, were most subject to damage.
Stebbings (1970) studied the effects of oil from the Torrey Canyon
spill on salt marshes in Brittany and found that these marshes were
1 ) Department of Botany and Department of Soil Science, respectively
North Carolina State University, Raleigh, North Carolina U.S.A. 27650
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