期刊
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY
卷 98, 期 -, 页码 279-291出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.dsr2.2012.09.003
关键词
Midwater fish; Bathypelagic zone; Mesopelagic zone; Species diversity; Vertical distribution; Vertical migration
类别
资金
- MAR-ECO
- National Science Foundation Biological Oceanography Program [OCE 0853761]
- Census of Marine Life field project
- NOAA Fisheries Service
- Natural Environment Research Council [NE/C512961/1, NE/C512988/1, NE/C513018/1, NE/C512996/1, NE/C51300X/1] Funding Source: researchfish
- NERC [NE/C513018/1, NE/C512996/1, NE/C512961/1, NE/C51300X/1, NE/C512988/1] Funding Source: UKRI
Only a miniscule fraction of the world's largest volume of living space, the ocean's midwater biome, has ever been sampled. As part of the International Census of Marine Life field project on Mid-Atlantic Ridge ecosystems (MAR-ECO), a discrete-depth trawling survey was conducted in 2009 aboard the NOAA FSV Henry B. Bigelow to examine the pelagic faunal assemblage structure and distribution over the Charlie-Gibbs Fracture Zone (CGFZ) of the northern Mid-Atlantic Ridge. Day/night sampling at closely spaced stations allowed the first characterization of diel vertical migration of pelagic nekton over the MAR-ECO study area. Discrete-depth sampling from 0-3000 m was conducted using a Norwegian Krill trawl with five codends that were opened and closed via a pre-programmed timer. Seventy-five species of fish were collected, with a maximum diversity and biomass observed between depths of 700-1900 m. A gradient in sea-surface temperature and underlying watermasses, from northwest to southeast, was mirrored by a similar gradient in ichthyofaunal diversity. Using multivariate analyses, eight deep-pelagic fish assemblages were identified, with depth as the primary discriminatory variable. Strong diel vertical migration (DVM) of the mesopelagic fauna was a prevalent feature of the study area, though the numerically dominant fish, Cyclothone microdon (Gonostomatidae), exhibited a broad (0-3000 m) vertical distribution and did not appear to migrate on a diel basis. Three patterns of vertical distribution were observed in the study area: (a) DVM of mesopelagic, and possibly bathypelagic, taxa; (b) broad vertical distribution spanning meso- and bathypelagic depths; and (c) discrete vertical distribution within a limited depth range. Overall species composition and rank order of abundance of fish species agreed with two previous expeditions to the CGFZ (1982-1983 and 2004), suggesting some long-term consistency in the ichthyofaunal composition of the study area, at least in the summer. Frequent captures of putative bathypelagic fishes, shrimps, and cephalopods in the epipelagic zone (0-200 m) were confirmed. The results of this expedition reveal distributional patterns unlike those previously reported for open-ocean ecosystems, with the implication of increased transfer efficiency of surface production to great depths in the mid-North Atlantic. (C) 2012 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据