Evidence for reduced post-spill recovery by the halophyte Sporobolus iocladus (Nees ex Trin.) Nees in oil contaminated sediments
In: Marine Pollution Bulletin. Macmillan: London. ISSN 0025-326X; e-ISSN 1879-3363, more
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Keywords |
Anthracene Biological development > Plant development > Germination > Seed germination Chemical compounds > Alkali metal compounds > Sodium compounds > Chlorides > Sodium chloride Chemical compounds > Organic compounds > Hydrocarbons Chemical compounds > Organic compounds > Hydrocarbons > Unsaturated hydrocarbons > Aromatic hydrocarbons > Naphthalene Halophytes Seeds Sporobolus iocladus Marine/Coastal |
Author keywords |
PAHs; NaCl; halophytes; naphthalene; anthracene; seed germination |
Abstract |
The germination behavior of Sporobolus iocladus seeds including germination percentage, accumulated germination percentage, the average incubation period to germination and germination velocity was studied under laboratory conditions. Treatments included six salinity regimes (0, 70, 140, 210, 280 and 350 mM NaCl) and three sources of oil hydrocarbons; Light Arabian Crude, polynuclear aromatic hydrocarbons (PAHs) including diaromatic or triaromatic hydrocarbons (in crude oil equivalent concentrations, COEC). The average incubation period needed for seeds to germinate was significantly longer for seeds germinated in 350 mM NaCl (6 ± 1.16 days) compared with the control (4 ± 00 days). The accumulated germination percentage gradually decreased with increasing salinity (control: 90 ± 10, while 350 mM NaCl: 63 ± 8.8). Oil hydrocarbons significantly affected all germination parameters of S. iocladus seeds regardless of salinity levels. COEC of di- and triaromatic hydrocarbons suppressed seed germination more than crude oil. Seeds exposed to diaromatic hydrocarbons failed to germinate. Hydrocarbon's salinity interaction significantly reduced the number of germinated S. iocladus seeds. It is concluded that hydrocarbon pollutants adversely affect S. iocladus through reducing germination. It is also suggested that the toxic effect of hydrocarbons on seeds is not solely mediated through their interaction with salinity. The ecological implications of these findings are discussed in relation to other studies on the post-spill recovery of halophytes. |
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