タイトル |
-
en
Seasonal changes in zooplankton abundance, biomass, size structure and dominant copepods in the Oyashio region analysed by an optical plankton counter
|
作成者 |
|
アクセス権 |
open access |
主題 |
-
Other
en
Eucalanus
-
Other
en
Metridia
-
Other
en
Neocalanus
-
Other
en
ESD
-
Other
en
life cycle
-
Other
en
OPC
-
NDC
660
|
内容注記 |
-
Abstract
en
To identify seasonal patterns of change in zooplankton communities, an optical plankton counter (OPC) and microscopic analysis were utilised to characterise zooplankton samples collected from 0 to 150 m and 0 to 500 m in the Oyashio region every one to three months from 2002 to 2007. Based on the OPC measurements, the abundance and biomass of zooplankton peaked in June (0–150 m) or August (150–500 m), depending on the depth stratum. The peak periods of the copepod species that were dominant in terms of abundance and biomass indicated species-specific patterns. Three Neocalanus species (Neocalanus cristatus, Neocalanus flemingeri and Neocalanus plumchrus) exhibited abundance peaks that occurred before their biomass peaks, whereas Eucalanus bungii and Metridia pacifica experienced biomass peaks before their abundance peaks. The abundance peaks corresponded to the recruitment periods of early copepodid stages, whereas the biomass peaks corresponded to the periods when the dominant populations reached the late copepodid stages (C5 or C6). Because the reproduction of Neocalanus spp. occurred in the deep layer (>500 m), their biomass peaks were observed when the major populations reached stage C5 after the abundance peaks of the early copepodid stages. The reproduction of E. bungii and M. pacifica occurred near the surface layer. These species first formed biomass peaks of C6 and later developed abundance peaks of newly recruited early copepodid stages. From the comparison between OPC measurements and microscopic analyses, seasonal changes in zooplankton biomass at depths of 0–150 m were governed primarily by E. bungii and M. pacifica, whereas those at depths of 150–500 m were primarily caused by the three Neocalanus species.
|
出版者 |
en
Elsevier
|
日付 |
|
言語 |
|
資源タイプ |
journal article |
出版タイプ |
AM |
資源識別子 |
HDL
http://hdl.handle.net/2115/56622
|
関連 |
-
isVersionOf
DOI
https://doi.org/10.1016/j.dsr.2014.06.003
|
収録誌情報 |
-
-
en
Deep Sea Research Part I: Oceanographic Research Papers
-
巻91
開始ページ115
終了ページ124
|
ファイル |
|
コンテンツ更新日時 |
2023-07-26 |