Eloïse Linda-Roselyne Savineau , Kathryn B. Cook , Sabena J. Blackbird , Gabriele Stowasser , Konstadinos Kiriakoulakis , Calum Preece , Sophie Fielding , Anna C. Belcher , George A. Wolff , Geraint A. Tarling , Daniel J. Mayor
{"title":"利用脂质和稳定同位素特征研究斯科舍海(南大洋)中层浮游动物的生理生态学","authors":"Eloïse Linda-Roselyne Savineau , Kathryn B. Cook , Sabena J. Blackbird , Gabriele Stowasser , Konstadinos Kiriakoulakis , Calum Preece , Sophie Fielding , Anna C. Belcher , George A. Wolff , Geraint A. Tarling , Daniel J. Mayor","doi":"10.1016/j.dsr.2024.104317","DOIUrl":null,"url":null,"abstract":"<div><p>The mesopelagic zooplankton community plays an important role in the cycling and sequestration of carbon via the biological pump. However, little is known about the physiology and ecology of key taxa found within this region, hindering our understanding of their influence on the pathways of energy and organic matter cycling. We sampled the eight most abundant zooplankton (<em>Calanoides acutus, Rhincalanus gigas, Paraeuchaeta</em> spp<em>.,</em> Chaetognatha<em>, Euphausia triacantha, Thysanoessa</em> spp<em>., Themisto gaudichaudii</em> and <em>Salpa thompsoni</em>) from within the mesopelagic zone in the Scotia Sea during a sinking diatom bloom and investigated their physiological ecology using lipid biomarkers and stable isotopic signatures of nitrogen. Data suggest that the large calanoid copepods, <em>C. acutus</em> and <em>R</em>. <em>gigas</em>, were in, or emerging from, a period of metabolic inactivity during the study period (November 15th – December 15th<sup>,</sup> 2017). Abundant, but decreasing lipid reserves in the predominantly herbivorous calanoid copepods, suggest these animals may have been metabolising previously stored lipids at the time of sampling, rather than deriving energy solely from the diatom bloom. This highlights the importance of understanding the timing of diapause of overwintering species as their feeding is likely to have an impact on the turnover of particulate organic matter (POM) in the upper mesopelagic. The δ<sup>15</sup>N signatures of POM became enriched with increasing depth, whereas all species of zooplankton except <em>T</em>. <em>gaudichaudii</em> did not. This suggests that animals were feeding on fresher, surface-derived POM, rather than reworked particles at depth, likely influencing the quantity and quality of organic matter leaving the upper mesopelagic. Our study highlights the complexity of mesopelagic food webs and suggests that the application of broad trophic functional types may lead to an incorrect understanding of ecosystem dynamics.</p></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0967063724000876/pdfft?md5=4ad1b987f2f700d77df2fe2119883429&pid=1-s2.0-S0967063724000876-main.pdf","citationCount":"0","resultStr":"{\"title\":\"Investigating the physiological ecology of mesopelagic zooplankton in the Scotia sea (Southern ocean) using lipid and stable isotope signatures\",\"authors\":\"Eloïse Linda-Roselyne Savineau , Kathryn B. Cook , Sabena J. Blackbird , Gabriele Stowasser , Konstadinos Kiriakoulakis , Calum Preece , Sophie Fielding , Anna C. Belcher , George A. Wolff , Geraint A. Tarling , Daniel J. Mayor\",\"doi\":\"10.1016/j.dsr.2024.104317\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The mesopelagic zooplankton community plays an important role in the cycling and sequestration of carbon via the biological pump. However, little is known about the physiology and ecology of key taxa found within this region, hindering our understanding of their influence on the pathways of energy and organic matter cycling. We sampled the eight most abundant zooplankton (<em>Calanoides acutus, Rhincalanus gigas, Paraeuchaeta</em> spp<em>.,</em> Chaetognatha<em>, Euphausia triacantha, Thysanoessa</em> spp<em>., Themisto gaudichaudii</em> and <em>Salpa thompsoni</em>) from within the mesopelagic zone in the Scotia Sea during a sinking diatom bloom and investigated their physiological ecology using lipid biomarkers and stable isotopic signatures of nitrogen. Data suggest that the large calanoid copepods, <em>C. acutus</em> and <em>R</em>. <em>gigas</em>, were in, or emerging from, a period of metabolic inactivity during the study period (November 15th – December 15th<sup>,</sup> 2017). Abundant, but decreasing lipid reserves in the predominantly herbivorous calanoid copepods, suggest these animals may have been metabolising previously stored lipids at the time of sampling, rather than deriving energy solely from the diatom bloom. This highlights the importance of understanding the timing of diapause of overwintering species as their feeding is likely to have an impact on the turnover of particulate organic matter (POM) in the upper mesopelagic. The δ<sup>15</sup>N signatures of POM became enriched with increasing depth, whereas all species of zooplankton except <em>T</em>. <em>gaudichaudii</em> did not. This suggests that animals were feeding on fresher, surface-derived POM, rather than reworked particles at depth, likely influencing the quantity and quality of organic matter leaving the upper mesopelagic. Our study highlights the complexity of mesopelagic food webs and suggests that the application of broad trophic functional types may lead to an incorrect understanding of ecosystem dynamics.</p></div>\",\"PeriodicalId\":51009,\"journal\":{\"name\":\"Deep-Sea Research Part I-Oceanographic Research Papers\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.3000,\"publicationDate\":\"2024-05-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S0967063724000876/pdfft?md5=4ad1b987f2f700d77df2fe2119883429&pid=1-s2.0-S0967063724000876-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Deep-Sea Research Part I-Oceanographic Research Papers\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0967063724000876\",\"RegionNum\":3,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"OCEANOGRAPHY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Deep-Sea Research Part I-Oceanographic Research Papers","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0967063724000876","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"OCEANOGRAPHY","Score":null,"Total":0}
Investigating the physiological ecology of mesopelagic zooplankton in the Scotia sea (Southern ocean) using lipid and stable isotope signatures
The mesopelagic zooplankton community plays an important role in the cycling and sequestration of carbon via the biological pump. However, little is known about the physiology and ecology of key taxa found within this region, hindering our understanding of their influence on the pathways of energy and organic matter cycling. We sampled the eight most abundant zooplankton (Calanoides acutus, Rhincalanus gigas, Paraeuchaeta spp., Chaetognatha, Euphausia triacantha, Thysanoessa spp., Themisto gaudichaudii and Salpa thompsoni) from within the mesopelagic zone in the Scotia Sea during a sinking diatom bloom and investigated their physiological ecology using lipid biomarkers and stable isotopic signatures of nitrogen. Data suggest that the large calanoid copepods, C. acutus and R. gigas, were in, or emerging from, a period of metabolic inactivity during the study period (November 15th – December 15th, 2017). Abundant, but decreasing lipid reserves in the predominantly herbivorous calanoid copepods, suggest these animals may have been metabolising previously stored lipids at the time of sampling, rather than deriving energy solely from the diatom bloom. This highlights the importance of understanding the timing of diapause of overwintering species as their feeding is likely to have an impact on the turnover of particulate organic matter (POM) in the upper mesopelagic. The δ15N signatures of POM became enriched with increasing depth, whereas all species of zooplankton except T. gaudichaudii did not. This suggests that animals were feeding on fresher, surface-derived POM, rather than reworked particles at depth, likely influencing the quantity and quality of organic matter leaving the upper mesopelagic. Our study highlights the complexity of mesopelagic food webs and suggests that the application of broad trophic functional types may lead to an incorrect understanding of ecosystem dynamics.
期刊介绍:
Deep-Sea Research Part I: Oceanographic Research Papers is devoted to the publication of the results of original scientific research, including theoretical work of evident oceanographic applicability; and the solution of instrumental or methodological problems with evidence of successful use. The journal is distinguished by its interdisciplinary nature and its breadth, covering the geological, physical, chemical and biological aspects of the ocean and its boundaries with the sea floor and the atmosphere. In addition to regular "Research Papers" and "Instruments and Methods" papers, briefer communications may be published as "Notes". Supplemental matter, such as extensive data tables or graphs and multimedia content, may be published as electronic appendices.