RESPONSES OF SELECTED US GULF-COAST MARSH MACROPHYTE SPECIES TO OILING AND COMMERCIAL CLEANERS

Citation
Sr. Pezeshki et al., RESPONSES OF SELECTED US GULF-COAST MARSH MACROPHYTE SPECIES TO OILING AND COMMERCIAL CLEANERS, Water, air and soil pollution, 107(1-4), 1998, pp. 185-195
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Environmental Sciences","Water Resources","Metereology & Atmospheric Sciences
Journal title
ISSN journal
0049-6979
Volume
107
Issue
1-4
Year of publication
1998
Pages
185 - 195
Database
ISI
SICI code
0049-6979(1998)107:1-4<185:ROSUGM>2.0.ZU;2-0
Abstract
A shoreline cleaner was tested to determine its effectiveness in remov ing different types of oil from selected US Gulf coastal marsh macroph ytes. Bulltongue (Sagittaria lancifolia L.), three cornered grass (Sci rpus olneyi E. & G.) and broadleaf cattail (Typha latifolia L.) were s ubjected to oil application and cleaning in a greenhouse and the subse quent effects on plant functions were evaluated during the period imme diately after treatment initiation. Plant stomatal functioning, photos ynthesis, respiration, regeneration, growth and biomass were monitored . Two types of oil, South Louisiana Crude (SLC) or Arabian Medium Crud e (AMC) were used. The treatments included: control (no oil or cleaner ), cleaner only (COREXIT 9580 only, no oil), oiled with SLC or AMC onl y (no cleaner), and oiled using SLC or AMC and cleaned with COREXIT 95 80 after two days. The existing leaves on the macrophytes at the time of treatment application directly subjected to oiling (but not cleaned ) did not recover from the effects of oiling in all of the study speci es. However, leaves under oil+cleaner treatments or leaves developed d uring the post-oiling period (new leaves) showed a different pattern o f response. For instance, in bulltongue plants, new leaves had stomata l conductances at or close to the Values recorded for control plants. However, new leaves and leaves subjected to oil+cleaner treatment in c attail and three-cornered plants, had stomatal conductances significan tly lower than their respective control plants. However, photosyntheti c and respiration data indicated no overall significant differences wi thin each species across treatments. Thus, the physiological functions of the study species had apparently recovered from the initial advers e effects of oiling within the experimental period. Based on photosynt hetic and respiration data, the study species sensitivity ranking is s imilar. Furthermore, there were no significant differences in physiolo gical responses of the study species to oil types. In addition, above- ground biomass was not affected significantly by the treatments in bul ltongue or cattail but was reduced significantly in three-corner plant s. Based on the overall physiological and biomass data, bulltongue was the least sensitive of the three species to SLC and AMC oil types tha n the other species while cattail appeared to be the most sensitive. A ny beneficial effects of the cleaner may be more pronounced in plant s pecies highly sensitive to specific oil types than the species studied .