کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4539136 1626618 2016 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Annual cycle and spatial trends in fatty acid composition of suspended particulate organic matter across the Beaufort Sea shelf
ترجمه فارسی عنوان
چرخه سالانه و روند فضایی در ترکیب اسید چرب مواد آلی ذرات معلق در سراسر فلات دریای بیوفورت
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
چکیده انگلیسی

Fatty acid profiles of suspended particulate organic matter (POM) were determined over an annual cycle (September 2003 to August 2004) on the Beaufort Sea shelf, Canadian Arctic. Special emphasis was placed on the nutritional quality of the fatty acid pool available to zooplankton by examining spatial and temporal patterns in the proportions of total polyunsaturated fatty acids (PUFA) and the essential fatty acids 22:6n−3 (DHA) and 20:5n−3 (EPA). EPA and DHA were the two most abundant PUFA throughout the study period. A log-ratio multivariate (LRA) analysis revealed strong structure in fatty acid profiles related to season and depth. Dominant fatty acids accounting for the observed trend included 18:5n−3, 18:4n−3, 16:1n−7, 20:5n-3, 18:0 and 20:3n−3. We observed a shift in fatty acid profiles from summer to autumn (e.g., from 16:1n−7 and EPA to 18:5n−3 and 18:4n−3) that likely corresponded to a shift in the relative importance of diatoms versus dinoflagellates, prymnesiophytes and/or prasinophytes to the POM pool. Fatty acid composition during winter was dominated by more refractory saturated fatty acids. A surprising finding was the depth and seasonal trend of 20:3n-3, which was higher in winter, aligned with 18:0 in the LRA, but behaved differently than other n−3 PUFA. We interpret fatty acid profiles during summer to be predominantly driven by phytoplankton inputs, whereas fatty acid profiles in winter were dominated by fatty acids that were left over after consumption and/or were generated by heterotrophs. The highest diatom inputs (EPA, the diatom fatty acid marker), n−3/n−6 ratios, and C16 PUFA index were located in an upwelling region off Cape Bathurst. This study is the first annual time series of fatty acid profiles of POM in Arctic seas, expanding our knowledge of the composition of POM throughout the dark season.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Estuarine, Coastal and Shelf Science - Volume 181, 5 November 2016, Pages 170–181
نویسندگان
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