A comparative investigation of the effects of south Louisiana crude oil on the vegetation of fresh, brackish and salt marshes

The impact of south Louisiana crude oil on the dominant vegetation, Spartina alterniflora, Spartina patens and Sagittaria lancifolia, of three types of coastal wetlands, salt, brackish and freshwater marshes, respectively, was studied. In the greenhouse, south Louisiana crude oil was applied to natural marsh sods at rates of 0, 4, 8, 16 and 24 l m−2. The photosynthetic rate of S. patens significantly decreased with increasing oil dosage after 1 month of oil application, while the photosynthetic rate of S. alterniflora was not significantly reduced by oil application until 3 months. The photosynthetic rate of S. lancifolia was not detrimentally affected by the oil treatments. Four months after oil application, live above-ground biomass production was significantly reduced at higher oil dosages for S. patens, was not affected in S. alterniflora, while S. lancifolia exhibited significantly higher total biomass at 24 l m−2 compared to the controls. The year following oil application, no regrowth of S. patens and S. alterniflora occurred at oil levels above 8 l m−2. In contrast, the regrowth of above-ground biomass of S. lancifolia increased with increasing oil dosage and resulted in monospecific communities at 16 and 24 l m−2. Furthermore, the residual oil in the soil greatly differed among the three marsh-types, with the highest concentrations in the S. patens soil sods and the lowest concentrations in S. alterniflora soil sods. This difference in oil residue among the marsh-types was mainly due to differences in soil organic content. The sensitivity of these marsh-types to south Louisiana crude oil increased in the following order: S. lancifolia, S. alterniflora and S. patens.

[1]  K. Moore,et al.  EFFECTS OF THE CHESAPEAKE BAY OIL SPILL ON SALT MARSHES OF THE LOWER BAY , 1977 .

[2]  D. Seliskar.  Morphometric variations of five tidal marsh halophytes along environmental gradients , 1985 .

[3]  R. Stebbings.  Recovery of salt marsh in Brittany sixteen months after heavy pollution by oil , 1970 .

[4]  R. E. Ferrell,et al.  The effects of crude oil on the growth of Spartinaalterniflora Loisel. and Spartina cynosuroides (L.) Roth , 1984 .

[5]  J. W. Webb,et al.  Relationship of Spartina alterniflora growth to sediment oil content following an oil spill , 1987 .

[6]  W. Armstrong,et al.  Oxygen Transport in the Salt Marsh Genus Puccinellia with Particular Reference to the Diffusive Resistance of the Root—Shoot Junction and the use of Paraffin Oil as a Diffusive Barrier in Plant Studies , 1983 .

[7]  R. Crawford,et al.  Variation in the Structure and Response to Flooding of Root Aerenchyma in some Wetland Plants , 1983 .

[8]  C. John Burk,et al.  A Four Year Analysis of Vegetation Following an Oil Spill in a Freshwater Marsh , 1977 .

[9]  R. Blackman,et al.  Oil in the sea: Inputs, fates, and effects: National Academy Press, Washington, DC. 1985. ISBN 0-309-03479-5. 601pp , 1986 .

[10]  M. Gleason,et al.  Influence of tidal inundation on internal oxygen supply of Spartina alterniflora and Spartina patens , 1981 .

[11]  R. Crawford,et al.  Plant Life in Anaerobic Environments , 1978 .

[12]  R. Clark.  The ecological effects of oil pollution on littoral communities: edited by E. B. Cowell. (Institute of Petroleum. London, 1971.) viii + 250 pp. Price £3.50. (Agents for overseas sales: Elsevier Publishing Company.) , 1972 .

[13]  J. W. Webb,et al.  SEASONAL RESPONSE OF SPARTINA ALTERNIFLORA TO OIL , 1985 .

[14]  I. Mendelssohn,et al.  The effect of a louisiana crude oil discharge from a pipeline break on the vegetation of a Southeast Louisiana brackish marsh , 1990 .

[15]  C. Hershner,et al.  Oil spills and the marine environment , 1974 .

[16]  G. Warren,et al.  Effect of four herbicides and two oils on leaf-cell membrane permeability*† , 1977 .

[17]  Stephen M. Testa,et al.  Restoration of petroleum-contaminated aquifers , 1990 .

[18]  R. Delaune,et al.  Effect of crude oil on a Louisiana Spartina alterniflora salt marsh , 1979 .

[19]  J. Gosselink,et al.  A note on standing crops of Spartina alterniflora in Texas and Florida. , 1975 .

[20]  P. Leendertse,et al.  The impact of oil pollution on salt marsh vegetation , 1991 .

[21]  K. L. Webb,et al.  The effect of chronic oil pollution on salt-marsh nitrogen fixation (acetylene reduction) , 1984 .

[22]  J. Morris,et al.  Chronic low level hydrocarbon amendments stimulate plant growth and microbial activity in salt-marsh microcosms. , 1990 .

[23]  J. Teal,et al.  Gas Transport in the Marsh Grass, Spartina alterniflora , 1966 .