Effects of an open-coast oil-production outfall on patterns of giant kelp (Macrocystis pyrifera) recruitment

✍ Scribed by D. C. Reed; R. J. Lewis; M. Anghera

• Book ID: 104747617
• Publisher: Springer-Verlag
• Year: 1994
• Tongue: English
• Weight: 822 KB
• Volume: 120
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00381938

✦ Synopsis

Field and laboratory experiments were used to investigate the spatial scale of benthic effects of an active nearshore produced-water (= aqueous wastes of oil and gas production) outfall on various components of recruitment in the giant kelp Macrocystispyrifera. Results showed that discernible effects on all parameters measured were limited to areas very close to the outfall (<50 m). Zoospore production in sporophytes transplanted to varying distances from the diffusers did not vary in a systematic way. Survival and successful reproduction (i.e., sporophyte production) of outplanted gametophytes varied significantly among experimental dates. Performance of these parameters was significantly reduced only at the site nearest the diffusers (5 m away). Poor gametophyte survival near the outfall may have resulted from exploitative competition with Beggiatoa sp. (a fast-growing filamentous marine bacteria that exploits areas high in hydrogen sulfide, an abundant constituent of the produced-water effluent) rather than from toxicity of produced water. Laboratory assays indicated that gametophyte reproduction and subsequent sporophyte production were inhibited at levels likely to occur within the near vicinity of the diffusers. Nonetheless, field data indicate that the lack of sporophyte production near the diffusers probably resulted from factors affecting gametophyte survival.

Communicated by M.