کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4535494 1326112 2008 19 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Spring production of Calanus finmarchicus at the Iceland–Scotland Ridge
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Spring production of Calanus finmarchicus at the Iceland–Scotland Ridge
چکیده انگلیسی

Distribution and reproduction activity of the calanoid copepod Calanus finmarchicus were studied in the waters between Scotland and Iceland in April 1997 during the expected time of the animals’ ascent to surface waters following diapause. Ascent was taking place on both sides of the Iceland–Scotland Ridge, apparently from two separate overwintering centers. The population on the Faroe Shelf (FS) most likely came from the overwintering population in the Faroe Shetland Channel (FSC). Per capita egg production was highest on the FS (>30 eggs female−1 d−1) and lowest in the Iceland Basin (10 eggs female−1 d−1). The maximum clutch size recorded was on the FS (145 eggs). As the maximum clutch sizes that females produced were between 40% and 77% (area averages of the station maximum rates) of their size-specific reproduction potential, it is argued that egg production rates were generally food-limited. Chlorophyll a concentrations were, at all but one station, under 1 μg L−1. Chlorophyll-based ingestion could, theoretically, support the observed average egg production rates in the Iceland Basin and on the FS but only about 30% of the observed production at the stations in the East Icelandic Current (EIC). The carbon assimilated through ingestion of phytoplankton, Calanus own eggs and nauplii in the EIC was estimated to be too low to support the frequently observed production of clutches consisting of over 100 eggs. Cannibalism on eggs and nauplii was not likely to have constituted a significant component of dietary carbon intake. However, a combination of feeding and assimilation of reserved lipid remaining from overwintering could be sufficient to explain the observed per capita egg production rates. C. finmarchicus copepod stages 1–3 were only recorded in considerable numbers only on the FS. This suggests higher survival rates of eggs in the shelf waters.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Deep Sea Research Part I: Oceanographic Research Papers - Volume 55, Issue 4, April 2008, Pages 471–489
نویسندگان
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