Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem
Predicting the impacts of ocean acidification in coastal habitats is complicated by bio-physical feedbacks between organisms and carbonate chemistry. Daily changes in pH and other carbonate parameters in coastal ecosystems, associated with processes such as photosynthesis and respiration, often grea...
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| Format: | Article |
| Language: | English |
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PeerJ Inc.
2018-05-01
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| Series: | PeerJ |
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| Online Access: | https://peerj.com/articles/4739.pdf |
| _version_ | 1827607492387930112 |
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| author | Matthew E.S. Bracken Nyssa J. Silbiger Genevieve Bernatchez Cascade J.B. Sorte |
| author_facet | Matthew E.S. Bracken Nyssa J. Silbiger Genevieve Bernatchez Cascade J.B. Sorte |
| author_sort | Matthew E.S. Bracken |
| collection | DOAJ |
| description | Predicting the impacts of ocean acidification in coastal habitats is complicated by bio-physical feedbacks between organisms and carbonate chemistry. Daily changes in pH and other carbonate parameters in coastal ecosystems, associated with processes such as photosynthesis and respiration, often greatly exceed global mean predicted changes over the next century. We assessed the strength of these feedbacks under projected elevated CO2 levels by conducting a field experiment in 10 macrophyte-dominated tide pools on the coast of California, USA. We evaluated changes in carbonate parameters over time and found that under ambient conditions, daytime changes in pH, pCO2, net ecosystem calcification (NEC), and O2 concentrations were strongly related to rates of net community production (NCP). CO2 was added to pools during daytime low tides, which should have reduced pH and enhanced pCO2. However, photosynthesis rapidly reduced pCO2 and increased pH, so effects of CO2 addition were not apparent unless we accounted for seaweed and surfgrass abundances. In the absence of macrophytes, CO2 addition caused pH to decline by ∼0.6 units and pCO2 to increase by ∼487 µatm over 6 hr during the daytime low tide. As macrophyte abundances increased, the impacts of CO2 addition declined because more CO2 was absorbed due to photosynthesis. Effects of CO2addition were, therefore, modified by feedbacks between NCP, pH, pCO2, and NEC. Our results underscore the potential importance of coastal macrophytes in ameliorating impacts of ocean acidification. |
| first_indexed | 2024-03-09T06:54:58Z |
| format | Article |
| id | doaj.art-3d33833a45c349ec969a257bec2d92ae |
| institution | Directory Open Access Journal |
| issn | 2167-8359 |
| language | English |
| last_indexed | 2024-03-09T06:54:58Z |
| publishDate | 2018-05-01 |
| publisher | PeerJ Inc. |
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| series | PeerJ |
| spelling | doaj.art-3d33833a45c349ec969a257bec2d92ae2023-12-03T10:05:00ZengPeerJ Inc.PeerJ2167-83592018-05-016e473910.7717/peerj.4739Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystemMatthew E.S. Bracken0Nyssa J. Silbiger1Genevieve Bernatchez2Cascade J.B. Sorte3Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of AmericaDepartment of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of AmericaDepartment of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of AmericaDepartment of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of AmericaPredicting the impacts of ocean acidification in coastal habitats is complicated by bio-physical feedbacks between organisms and carbonate chemistry. Daily changes in pH and other carbonate parameters in coastal ecosystems, associated with processes such as photosynthesis and respiration, often greatly exceed global mean predicted changes over the next century. We assessed the strength of these feedbacks under projected elevated CO2 levels by conducting a field experiment in 10 macrophyte-dominated tide pools on the coast of California, USA. We evaluated changes in carbonate parameters over time and found that under ambient conditions, daytime changes in pH, pCO2, net ecosystem calcification (NEC), and O2 concentrations were strongly related to rates of net community production (NCP). CO2 was added to pools during daytime low tides, which should have reduced pH and enhanced pCO2. However, photosynthesis rapidly reduced pCO2 and increased pH, so effects of CO2 addition were not apparent unless we accounted for seaweed and surfgrass abundances. In the absence of macrophytes, CO2 addition caused pH to decline by ∼0.6 units and pCO2 to increase by ∼487 µatm over 6 hr during the daytime low tide. As macrophyte abundances increased, the impacts of CO2 addition declined because more CO2 was absorbed due to photosynthesis. Effects of CO2addition were, therefore, modified by feedbacks between NCP, pH, pCO2, and NEC. Our results underscore the potential importance of coastal macrophytes in ameliorating impacts of ocean acidification.https://peerj.com/articles/4739.pdfClimate changeNet community productionOcean acidificationRocky intertidalPhotosynthesis |
| spellingShingle | Matthew E.S. Bracken Nyssa J. Silbiger Genevieve Bernatchez Cascade J.B. Sorte Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem PeerJ Climate change Net community production Ocean acidification Rocky intertidal Photosynthesis |
| title | Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem |
| title_full | Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem |
| title_fullStr | Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem |
| title_full_unstemmed | Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem |
| title_short | Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem |
| title_sort | primary producers may ameliorate impacts of daytime co2 addition in a coastal marine ecosystem |
| topic | Climate change Net community production Ocean acidification Rocky intertidal Photosynthesis |
| url | https://peerj.com/articles/4739.pdf |
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