Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers
The Galápagos Archipelago is a globally significant biodiversity hotspot. However, compared to the relatively well-known megafauna, the distribution and ecological significance of marine protists in this system are poorly understood. To gain an understanding of the protistan assemblages across troph...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-05-01
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| Series: | Frontiers in Marine Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fmars.2022.811979/full |
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| author | Se Hyeon Jang Se Hyeon Jang Prisca Lim Olivia Torano Erika F. Neave Harvey Seim Adrian Marchetti |
| author_facet | Se Hyeon Jang Se Hyeon Jang Prisca Lim Olivia Torano Erika F. Neave Harvey Seim Adrian Marchetti |
| author_sort | Se Hyeon Jang |
| collection | DOAJ |
| description | The Galápagos Archipelago is a globally significant biodiversity hotspot. However, compared to the relatively well-known megafauna, the distribution and ecological significance of marine protists in this system are poorly understood. To gain an understanding of the protistan assemblages across trophic modes, an intensive oceanographic survey was conducted in the Galápagos Marine Reserve (GMR) in October of 2018. The Equatorial Undercurrent (EUC)-influenced region had higher chlorophyll-a (Chl-a) concentrations than those of the eastern regions of the archipelago, along with higher abundances of protistan grazers. Specifically, proportions of autotrophic and potentially mixotrophic dinoflagellates were higher in the EUC, whereas in the eastern regions, heterotrophic dinoflagellates and chlorophytes dominated. Taxonomic composition and biochemical indicators suggested proportions of micrograzers and their associated heterotrophic biomass was higher in the oligotrophic, low Chl-a regions in the east. We also report observations from a dinoflagellate bloom in the western archipelago, which was heavily influenced by upwelling of the EUC. The red tide-forming dinoflagellate Scrippsiella lachrymosa was highly detected through light microscopy and DNA amplicon sequencing. In addition, the heterotrophic dinoflagellate Polykrikos kofoidii was detected and, based on cell densities observed in this study and grazing rates obtained from the literature, estimated to potentially graze up to 62% of S. lachrymosa bloom population. Our findings thus provide new insights into the composition of micrograzers and their potential roles in structuring protistan communities in the Galápagos Archipelago. |
| first_indexed | 2024-12-12T10:51:21Z |
| format | Article |
| id | doaj.art-075880e5de2b4de589694253ae4320a4 |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-12-12T10:51:21Z |
| publishDate | 2022-05-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-075880e5de2b4de589694253ae4320a42022-12-22T00:26:45ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452022-05-01910.3389/fmars.2022.811979811979Protistan Communities Within the Galápagos Archipelago With an Emphasis on MicrograzersSe Hyeon Jang0Se Hyeon Jang1Prisca Lim2Olivia Torano3Erika F. Neave4Harvey Seim5Adrian Marchetti6Department of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesDepartment of Oceanography, Chonnam National University, Gwangju, South KoreaDepartment of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesDepartment of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesDepartment of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesDepartment of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesDepartment of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesThe Galápagos Archipelago is a globally significant biodiversity hotspot. However, compared to the relatively well-known megafauna, the distribution and ecological significance of marine protists in this system are poorly understood. To gain an understanding of the protistan assemblages across trophic modes, an intensive oceanographic survey was conducted in the Galápagos Marine Reserve (GMR) in October of 2018. The Equatorial Undercurrent (EUC)-influenced region had higher chlorophyll-a (Chl-a) concentrations than those of the eastern regions of the archipelago, along with higher abundances of protistan grazers. Specifically, proportions of autotrophic and potentially mixotrophic dinoflagellates were higher in the EUC, whereas in the eastern regions, heterotrophic dinoflagellates and chlorophytes dominated. Taxonomic composition and biochemical indicators suggested proportions of micrograzers and their associated heterotrophic biomass was higher in the oligotrophic, low Chl-a regions in the east. We also report observations from a dinoflagellate bloom in the western archipelago, which was heavily influenced by upwelling of the EUC. The red tide-forming dinoflagellate Scrippsiella lachrymosa was highly detected through light microscopy and DNA amplicon sequencing. In addition, the heterotrophic dinoflagellate Polykrikos kofoidii was detected and, based on cell densities observed in this study and grazing rates obtained from the literature, estimated to potentially graze up to 62% of S. lachrymosa bloom population. Our findings thus provide new insights into the composition of micrograzers and their potential roles in structuring protistan communities in the Galápagos Archipelago.https://www.frontiersin.org/articles/10.3389/fmars.2022.811979/fullupwellingred tidebloomheterotrophic protistmicrozooplanktonmetabarcoding |
| spellingShingle | Se Hyeon Jang Se Hyeon Jang Prisca Lim Olivia Torano Erika F. Neave Harvey Seim Adrian Marchetti Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers Frontiers in Marine Science upwelling red tide bloom heterotrophic protist microzooplankton metabarcoding |
| title | Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers |
| title_full | Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers |
| title_fullStr | Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers |
| title_full_unstemmed | Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers |
| title_short | Protistan Communities Within the Galápagos Archipelago With an Emphasis on Micrograzers |
| title_sort | protistan communities within the galapagos archipelago with an emphasis on micrograzers |
| topic | upwelling red tide bloom heterotrophic protist microzooplankton metabarcoding |
| url | https://www.frontiersin.org/articles/10.3389/fmars.2022.811979/full |
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