Biomass and production of Euphausia pacifica off south-eastern Hokkaido (41–43°N), Sanriku (38–41°N), and Joban (36–38°N) were investigated every two months from March 1997 to February 1998. High biomass was found in summer-autumn off south-eastern Hokkaido, and in the late winter-early summer off Sanriku and Joban. Annual mean biomass was 381, 314 and 258 mg C/m2 off south-eastern Hokkaido, Sanriku, and Joban, respectively. The total production (sum of flesh, moults and eggs) during the survey period off south-eastern Hokkaido (3829 mg C/m2) was comparable with that off Sanriku (3872 mg C/m2); both were much higher than that off Joban (2243 mg C/m2). Somatic production during the survey period contributed the highest proportion (51.5–70.9%) to the total production in each coastal area. The somatic production-biomass ratio in each coastal area (5.2–6.9) was an intermediate value among 25 populations of 16 euphausiid species previously reported. This effect resulted from the negative factor of stagnated growth of adults during summer-winter, coupled with positive factors including continuous occurrence of larvae which show high growth rate throughout the year off Sanriku and Joban, and the numerous larvae occurring in October off south-eastern Hokkaido.
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机译：从1997年3月至1998年2月，每两个月调查一次北海道东南部（41-43°N），三陆（38-41°N）和Joban（36-38°N）附近的太平洋大虾（Euphausia pacifica）的生物量和产量。在北海道东南部的夏季秋季，以及在三陆和Joban的冬末夏初发现了生物质。北海道东南部，三陆和Joban的年平均生物量分别为381、314和258 mg C / m2。在调查期间，北海道东南部（3829 mg C / m2）的总产量（肉，毛和卵的总和）与三陆（Sanriku）附近的总产量（3872 mg C / m2）相当;两者均比Joban（2243 mg C / m2）高得多。在调查期间，体细胞产量在每个沿海地区的总产量中所占比例最高（51.5-70.9％）。在每个沿海地区（5.2–6.9）的体细胞生产-生物量比率在先前报告的25个16个桔小类物种的种群中处于中间值。造成这种影响的原因是夏季冬季成人停滞不前的负面因素，加上积极因素，包括连续出现三陆和常磐地区全年幼虫率高的幼虫，以及十月东南部大量幼虫。北海道。
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