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A baseline assessment of coastal pH variability in a temperate South African embayment: implications for biological ocean acidification research

A baseline assessment of coastal pH variability in a temperate South African embayment:... Compared with the open ocean, knowledge of pH variability in coastal waters is rudimentary, especially in Africa. This is concerning as quantifying local pH conditions is critical when assessing the response of coastal species to future ocean acidification scenarios. The objective of this study was to capture some of the variability in pH at scales and sites relevant to coastal marine organisms in a South African temperate embayment (Algoa Bay, Indian Ocean). We used a sampling approach that captured spatial (at a resolution of ∼10 km), monthly and diel (24-hour) variability in pH and associated physical and biological parameters at offshore and shallow inshore sites in Algoa Bay. We found that pH and associated parameters (temperature, calculated pCO2, chlorophyll a) varied over space and time in Algoa Bay. The range in pH was 0.30 units at offshore sites and 0.46 at inshore sites, and the average pH was 8.10 (SD 0.06) and 8.10 (SD 0.13) at these sites, respectively, which is typical for coastal environments. Our results showed that both biological factors (at the offshore sites) and salinity (at the inshore sites) may influence temporal and spatial variability in pH. We also identified a shallow inshore site with high levels of macroalgal growth that had consistently higher average daytime pH levels (8.33 [SD 0.07]), which may serve as an ocean acidification refuge for coastal marine species. This is the first comprehensive pH-monitoring study to be implemented in a nearshore coastal area in Africa and provides recommendations for monitoring in other understudied regions. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png African Journal of Marine Science Taylor & Francis

A baseline assessment of coastal pH variability in a temperate South African embayment: implications for biological ocean acidification research

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A baseline assessment of coastal pH variability in a temperate South African embayment: implications for biological ocean acidification research

Abstract

Compared with the open ocean, knowledge of pH variability in coastal waters is rudimentary, especially in Africa. This is concerning as quantifying local pH conditions is critical when assessing the response of coastal species to future ocean acidification scenarios. The objective of this study was to capture some of the variability in pH at scales and sites relevant to coastal marine organisms in a South African temperate embayment (Algoa Bay, Indian Ocean). We used a sampling approach that...
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Publisher
Taylor & Francis
Copyright
© 2022 NISC (Pty) Ltd
ISSN
1814-2338
eISSN
1814-232X
DOI
10.2989/1814232X.2022.2147999
Publisher site
See Article on Publisher Site

Abstract

Compared with the open ocean, knowledge of pH variability in coastal waters is rudimentary, especially in Africa. This is concerning as quantifying local pH conditions is critical when assessing the response of coastal species to future ocean acidification scenarios. The objective of this study was to capture some of the variability in pH at scales and sites relevant to coastal marine organisms in a South African temperate embayment (Algoa Bay, Indian Ocean). We used a sampling approach that captured spatial (at a resolution of ∼10 km), monthly and diel (24-hour) variability in pH and associated physical and biological parameters at offshore and shallow inshore sites in Algoa Bay. We found that pH and associated parameters (temperature, calculated pCO2, chlorophyll a) varied over space and time in Algoa Bay. The range in pH was 0.30 units at offshore sites and 0.46 at inshore sites, and the average pH was 8.10 (SD 0.06) and 8.10 (SD 0.13) at these sites, respectively, which is typical for coastal environments. Our results showed that both biological factors (at the offshore sites) and salinity (at the inshore sites) may influence temporal and spatial variability in pH. We also identified a shallow inshore site with high levels of macroalgal growth that had consistently higher average daytime pH levels (8.33 [SD 0.07]), which may serve as an ocean acidification refuge for coastal marine species. This is the first comprehensive pH-monitoring study to be implemented in a nearshore coastal area in Africa and provides recommendations for monitoring in other understudied regions.

Journal

African Journal of Marine Science – Taylor & Francis

Published: Oct 2, 2022

Keywords: Algoa Bay; carbonate chemistry; coastal acidification; monitoring; pH variability; seawater

References

  • Biologists ignore ocean weather at their peril
  • The fish community of East Cape tidal pools and an assessment of the nursery function of this habitat
  • The estimation of annual primary production in a high energy surf-zone
  • Tide-induced pulsing of nutrient discharge from an unconfined aquifer into an Anaulus australisdominated surf-zone
  • Drivers of pH variability in coastal ecosystems
  • Variability of the carbonate chemistry in a shallow, seagrass-dominated ecosystem: implications for ocean acidification experiments
  • Standard potential of the reaction: AgCl (s) + 12H2 (g) = Ag (s) + HCl (aq), and the standard acidity constant of the ion HSO4 − in synthetic sea water from 273.15 to 318.15 K
  • A comparison of the equilibrium constants for the dissociation of carbonic acid in seawater media
  • Ocean acidification: the other CO2 problem
  • Is ocean acidification an open-ocean syndrome? Understanding anthropogenic impacts on seawater pH
  • Impacts of ocean acidification on marine fauna and ecosystem processes
  • Evidence for upwelling of corrosive “acidified” water onto the continental shelf
  • Ocean acidification: present conditions and future changes in a high-CO2 world
  • High temporal and spatial variability of dissolved oxygen and pH in a nearshore California kelp forest
  • Seasonal variability of fCO2 in the Angola-Benguela region
  • Upwelling and the occurrence of cold water around Cape Recife, Algoa Bay, South Africa
  • Coastal upwelling on the far eastern Agulhas Bank associated with large meanders in the Agulhas Current
  • Is the southern Benguela a significant regional sink of CO2?
  • Rapid progression of ocean acidification in the California Current System
  • Ocean acidification and its potential effects on marine ecosystems
  • Spatiotemporal variability and long-term trends of ocean acidification in the California Current System
  • Biological mechanisms supporting adaptation to ocean acidification in coastal ecosystems
  • High-frequency dynamics of ocean pH: a multi-ecosystem comparison
  • Update on the custodianship role in relation to SDG 14 indicators (IOC/EC-LI/2 Annex 6 rev.)
  • Surface ocean pH and buffer capacity: past, present and future
  • Ocean pH time-series and drivers of variability along the northern Channel Islands, California, USA
  • Exploring the complexity of ocean acidification: an ecosystem comparison of coastal pH variability
  • Substantial role of macroalgae in marine carbon sequestration
  • Land-derived inorganic nutrient loading to coastal waters and potential implications for nearshore plankton dynamics
  • Reconciliation of pH25 and pHinsitu acidification rates of the surface oceans: a simple conversion using only in situ temperature
  • Drought in the Eastern Cape region of South Africa and trends in rainfall characteristics
  • Abiotic versus biotic drivers of ocean pH variation under fast sea ice in McMurdo Sound, Antarctica
  • Appropriate pCO2 treatments in ocean acidification experiments
  • Significance of groundwater nitrogen input to a beach/surf zone ecosystem
  • Sand beach energetics: an ecosystem approach towards a high energy interface
  • Photosynthesis and light-dependent proton pumps increase boundary layer pH in tropical macroalgae: a proposed mechanism to sustain calcification under ocean acidification
  • Measurement of the apparent dissociation constants of carbonic acid in seawater at atmospheric pressure
  • High pH in shallow-water macroalgal habitats
  • Shellfish face uncertain future in high CO2 world: influence of acidification on oyster larvae calcification and growth in estuaries
  • Global Ocean Acidification Observing Network: requirements and governance plan
  • Abiotic and biotic interactions in the diffusive boundary layer of kelp blades create a potential refuge from ocean acidification
  • Comparison of different methods for chlorophyll and phaeopigment determination
  • Seaweed nutrient physiology: application of concepts to aquaculture and bioremediation
  • The oceanic sink for anthropogenic CO2
  • Carbon dioxide fluxes in the Benguela upwelling system during winter and spring: a comparison between 2005 and 2006
  • Cold water events in Algoa Bay and along the Cape south coast, South Africa, in March/April 1987
  • Oceanic variability in the western sector of Algoa Bay, South Africa
  • A sensor for in situ indicator-based measurements of seawater pH
  • Eutrophication induced CO2-acidification of subsurface coastal waters: interactive effects of temperature, salinity, and atmospheric pCO2
  • Distribution patterns of rip frequency and intensity in Algoa Bay, South Africa
  • An enhanced ocean acidification observing network: from people to technology to data synthesis and information exchange
  • Influences of riverine and upwelling waters on the coastal carbonate system off Central Chile and their ocean acidification implications
  • Macroalgae may mitigate ocean acidification effects on mussel calcification by increasing pH and its fluctuations
  • Ocean acidification in the coastal zone from an organism’s perspective: multiple system parameters, frequency domains, and habitats
  • Coastal acidification induced by tidal-driven submarine groundwater discharge in a coastal coral reef system
  • Benthic algal communities of shallow reefs in the Eastern Cape: availability of abalone habitat
  • Seaweed farms provide refugia from ocean acidification