Adjusting metabolic rates and critical oxygen tension in planktonic copepods under increasing hypoxia in highly productive coastal upwelling zones

Author:

Frederick Leissing1ORCID,Urbina Mauricio A.23ORCID,Jorquera Erika4ORCID,Escribano Ruben35ORCID

Affiliation:

1. University of Concepción Concepción Chile

2. Department of Zoology Faculty of Natural Sciences and Oceanography, University of Concepción Concepción Chile

3. Millennium Institute of Oceanography Chile

4. Facultad de Ciencias Universidad Católica de la Santísima Concepción Concepción Chile

5. Department of Oceanography Faculty of Natural Sciences and Oceanography, University of Concepción Concepción Chile

Abstract

AbstractOngoing ocean deoxygenation is threatening marine organisms globally. In eastern boundary upwelling systems, planktonic copepods dominate the epipelagic zooplankton, being crucial in the marine food web. Yet, they must cope with severe hypoxia caused by shoaling of the oxygen minimum zone. Based on laboratory experiments during 2021, we found differential responses in the metabolic rate (MR) and critical oxygen partial pressure of three abundant copepods. Calanoides patagoniensis doubled its MR during the upwelling season, so better exploiting the spring phytoplankton bloom for feeding and reproduction while maintaining their critical oxygen partial pressure unchanged between seasons. Contrastingly, Paracalanus cf. indicus and Acartia tonsa, maintained their MRs throughout seasons, but significantly increased their critical oxygen partial pressure during the upwelling period, becoming less tolerant to hypoxia. Field observations showed that oxygen levels equal to or lower than the critical oxygen partial pressure is a common condition (70% of occurrence) that copepods encounter during the year in the upper 50 m layer. These findings suggest a species‐dependent trade‐off between the MR and the critical oxygen partial pressure, where some species can maintain the latter despite fluctuations in their MR (improved hypoxia tolerance) or maintain their MR at the expenses of a larger critical oxygen partial pressure (improved energy expenditures). These adaptive responses, under oxygen levels equal to or lower than the critical oxygen partial pressure, suggest that exacerbated hypoxia, driven by ocean deoxygenation and increased upwelling, will alter copepod distribution and cause higher copepod mortality, with potentially drastic consequences for marine food webs.

Funder

Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias

Fondo Nacional de Desarrollo Científico y Tecnológico

Agencia Nacional de Investigación y Desarrollo

Publisher

Wiley

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3