|Passow, Uta||University of California-Santa Barbara (UCSB-MSI)||Principal Investigator, Contact|
|Alldredge, Alice L.||University of California-Santa Barbara (UCSB-MSI)||Co-Principal Investigator|
|Rossi, Tullio||University of California-Santa Barbara (UCSB-MSI)||Contact|
|Copley, Nancy||Woods Hole Oceanographic Institution (WHOI BCO-DMO)||BCO-DMO Data Manager|
|Gegg, Stephen R.||Woods Hole Oceanographic Institution (WHOI BCO-DMO)||BCO-DMO Data Manager|
Series 3: Skeletonema marinoi growth and aggregation under future ocean acidification conditions
- Phase 1: Cell Growth Phase
- Experiments 1 and 2
2.1 General set up: The experiment consisted of two treatments (Present and Future) representing different pCO2 conditions and two sequential experimental phases: the cell growth phase and the aggregation phase. The experiment was sequentially replicated. The two replicates are going to be referred as Experiment 1 and Experiment 2.
2.2 Cell growth phase: During the cell growth phase, the effect of OA was tested on a culture of S. marinoi that was incubated for five days, in 5 l transparent bags. Two replicate bags were used for each treatment. The pH was measured daily immediately after collection in each bag, while the TA samples were collected for later analysis in one sample per treatment at the beginning and at the end of the cell growth phase. The algal cells were counted, sized and their instantaneous in vivo chlorophyll fluorescence (Ft) and quantum yield (Qy) were measured daily in the morning. The concentration of bacteria and TEP were measured at t 0 ,t2.8 and t4.6. The nutrients concentration was sampled at t2.8 and t4.6. The dry weight, particulate carbon, hydrogen and nitrogen were measured at t4.6. After 5 days the cultures in the two bags per treatment were pooled, the carbonate system was readjusted to the starting conditions and subsequently they were inoculated into cylindrical rolling tanks.
2.3 Aggregation phase: The aggregation phase consisted in the incubation of the cultures into cylindrical tanks on rolling tables (Edmondson, 1989). A total of 8 tanks (4 replicates per treatment) were incubated over the rolling table for two days in the darkness in the environmental room at 15°C. Solid body rotation is established in these rolling tanks within less than three hours (Ploug, Terbrüggen, Kaufmann, Wolf- Gladrow, & Passow, 2010) and the sinking of particles through the water column was simulated and aggregation promoted. After 38 hours of incubation the aggregates sinking velocity, number and size were measured. The algal cell number, bacterial cell number, TEP, dry weight, particulate carbon, hydrogen and nitrogen were evaluated, both for the aggregated fraction and for the surrounding water. The carbonate system was characterized by measuring pH in all the tanks and TA in one tank per treatment.
BCO-DMO Processing Notes
Generated from original .xlsx file "Data T.Rossi.xlsx", Version in e-mail of 02May2013 contributed by Tullio Rossi
Sheets: "Experiment 1 Phase 1" and "Experiment 2 Phase 1"
Note: Earlier version of spreadsheet contained erroneous data corrected in the 02May2013 version
- Approx Lat/Lon of Passow Lab appended to enable data discovery in MapServer
- Column inserted for Experiment Number
- Column inserted for Bag Description
- Date/Time split into two columns
- Date reformatted to YYYYMMDD
- Time reformatted to HHMM
- Parameter names edited to conform to BCO-DMO parameter naming conventions
- "nd" (no data) inserted into blank cells
- Column inserted for "Silicate" in Experiment 2 (all "nd") for compatibility with Experiment 1
- Version 2017-10-11 is revised slightly from version 2013-05-02 by reducing digits right of decimal (rounded).
|t||Cumulative time expressed in days starting at t=0 (first day of experiment)||Decimal days|
|Date||Date at which the bags were sampled for the measurement of the various parameter||YYYYMMDD|
|Time||Time at which the bags were sampled for the measurement of the various parameter||HHMM|
|Algal_Count||Algal Culture Parameters - Count||Cells/mL|
|Algal_Ft||Algal Culture Parameters - In Vivo Instantaneous Chlorophyll Fluorescence (Ft)||Relative units|
|Algal_Qy||Algal Culture Parameters - In Vivo Instantaneous Quantum Yield (Qy)||Dimensionless|
|pH_at_15_C||Carbonate System - pH - At Ambient Temperature of 15degC||Total pH scale|
|TA||Carbonate System - Total Alkalinity (TA)||umol kg -1|
|DOC||Dissolved Organic Carbon (DOC)||umol per liter|
|TEP||Transparent Exopolymer Particles (TEP). In ug of Gxeq (xanthan gum equivalent) per liter. This is an absorbance equivalence.||Gxeq/L|
|Nitrite_plus_Nitrate||Nutrients - Nitrite + Nitrate||umol per liter|
|Phosphate||Nutrients - Phosphate||umol per liter|
|Silicate||Nutrients - Silicate||umol per liter|
|Lab_Id||Lab Id - Lab identifier where experiments were conducted||text|
|Lat||Approximate Latitude Position of Lab; South is negative||decimal degrees|
|Lon||Approximate Longitude Position of Lab; West is negative||decimal degrees|
UCSB MSI Passow
|Start Date|| |
|End Date|| |
Results form a series of controlled laboratory experiments investigating the effect of altered carbonate system chemistry on the abiotic formation of TEP
Will Ocean Acidification Diminish Particle Aggregation and Mineral Scavenging, Thus Weakening the Biological Pump?
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
The pH of the ocean is predicted to decrease by 0.2-0.5 pH units in the next 50 to100 years as a result of increasing atmospheric CO2. To date almost all the research on impending ocean acidification has focused on the impacts to calcifying organisms and the carbonate system. However, ocean acidification will also affect other significant marine processes that are pH dependent.
In this project, researchers at the University of California at Santa Barbara will investigate the impact of ocean acidification on the organic carbon or 'soft tissue' biological pump. They predict that a decline in oceanic pH will result in an increase in the protonation of negatively charged substances, especially of Transparent Exopolymer Particles (TEP), the gel-like particles that provide the matrix of aggregates and bind particles together. A decreased polarity of these highly surface-active particles may reduce their "stickiness" resulting in decreased aggregation of organic-rich particles and a decreased ability of aggregates to scavenge and retain heavy ballast minerals. A reduction in aggregation will lower the fraction of POC enclosed in fast-sinking aggregates. Decreased scavenging of minerals by aggregates will result in reduced sinking velocities and consequently a decline in the fraction of material escaping degradation in the water column. Both processes ultimately reduce carbon flux to depth. The resulting weakening of the biological pump will alter pelagic ecology and potentially produce a positive feed-back pathway that further increases atmospheric CO2 concentrations.
The research team will experimentally investigate TEP-production, aggregation rates and aggregate characteristics, mineral scavenging and sinking velocity as a function of ocean acidification, because these parameters are susceptible to pH and central in determining sedimentation rate of organic carbon. They will determine potential changes in the abiotic formation of TEP or in the release rate of TEP or TEP-precursors by phytoplankton that have been adapted to increased CO2 regimes for multiple generations, up to 1000 doublings. Additionally, they will experimentally test potential changes in the aggregation rate of adapted phytoplankton and natural particles, and measure impacts on scavenging rates of ballast minerals by aggregates. Effects of various acidification levels on aggregate characteristics, including size, composition, density, and sinking velocity will also be determined. These results are expected to provide parameterization for a predictive model that will be used to investigate the impact of changing ballasting or aggregation on carbon flux.
Broader impact: Climate and environmental change are a global challenge to society. We need to know if possible positive feed back mechanisms to the biological pump will further increase atmospheric CO2 in order to prepare for and hopefully manage future climate changes.
These data are also available at Pangea
Passow U (2012) The Abiotic Formation of Tep under Ocean Acidification Scenarios. Marine Chemistry 128-129:72-80
PUBLICATIONS PRODUCED AS A RESULT OF THIS RESEARCH
Bathmann U, Passow U. "Global Erwaermung. Kohlenstoffpumpen im Ozean steuern das Klima.," Biologie in unserer Zeit 5, v.5, 2010.
Benner I, Passow U. "Utilization of organic nutrients by coccolithophores," Marine Ecology Progress Series, v.404, 2010, p. 21.
Feng Y, Hare C, Leblanc K, Rose J, Zhang Y, DiTullio G, Lee P, Wilhelm S, Rowe J, Sun J, Nemcek N, Gueguen C, Passow U, Benner I, Brown C, Hutchins D. "Effects of increased pCO2 and temperature on the North Atlantic spring bloom. I. The phytoplankton community and biogeochemical response," Marine Ecology Progress Series, v.388, 2009, p. 13.
Gaerdes A, Iversen MH, Grossart H-P, Passow U, Ullrich M. "Diatom associated bacteria are required for aggregation of Thalassiosira weissflogii.," ISME Journal, 2010, p. 1.
Leblanc K, Hare CE, Feng Y, Berg GM, DiTullio GR, Neeley A, Benner I, Sprengel C, Beck A, Sanudo-Wilhelmy SA, Passow U, Klinck K, Rowe JM, Wilhelm SW, Brown CW, Hutchins DA. "Distribution of calcifying and silicifying phytoplankton in relation to environmental and biogeochemical parameters during the late stages of the 2005 North East Atlantic Spring Bloom," Biogeosciences, v.6, 2009, p. 2155.
Ploug H, Terbruggen A, Kaufmann A, Wolf-Gladrow D, Passow U. "A novel method to measure particle sinking velocity in vitro, and its comparison to three other in vitro methods.," Limnolgy and Oceanography Methods, v.8, 2010, p. 386.
Passow, U., Rocha, C.L.D.L., Fairfield, C., Schmidt, K., 2014. Aggregation as a function of pCO2 and mineral particles. Limnology and Oceanography 59 (2), 532-547.
De La Rocha, C.L., Passow, U., 2014. The biological pump. In: Turekian, K.K., Holland, H.D. (Eds.), Treatise on Geochemistry. Elsevier, Oxford, pp. 93-122.
Boyd, P., Rynearson, T., Armstrong, E., Fu, F., Hayashi, K., Hu, Z., Hutchins, D., Kudela, R., Litchman, E., Mulholland, M., Passow, U., Strzepek, R., Whittaker, K., Yu, E., Thomas, M., 2013. Marine Phytoplankton Temperature versus Growth Responses from Polar to Tropical Waters - Outcome of a Scientific Community-Wide Study. PLoS ONE 8 (5), e63091.
Passow, U., Carlson, C., 2012. The Biological Pump in a High CO2 World. Marine Ecology Progress Series 470, 249-271.
NSF Climate Research Investment (CRI) activities that were initiated in 2010 are now included under Science, Engineering and Education for Sustainability NSF-Wide Investment (SEES). SEES is a portfolio of activities that highlights NSF's unique role in helping society address the challenge(s) of achieving sustainability. Detailed information about the SEES program is available from NSF (https://www.nsf.gov/funding/pgm_summ.jsp?pims_id=504707).
In recognition of the need for basic research concerning the nature, extent and impact of ocean acidification on oceanic environments in the past, present and future, the goal of the SEES: OA program is to understand (a) the chemistry and physical chemistry of ocean acidification; (b) how ocean acidification interacts with processes at the organismal level; and (c) how the earth system history informs our understanding of the effects of ocean acidification on the present day and future ocean.
Solicitations issued under this program:
NSF 10-530, FY 2010-FY2011
NSF 12-500, FY 2012
NSF 12-600, FY 2013
NSF 13-586, FY 2014
NSF 13-586 was the final solicitation that will be released for this program.
1st U.S. Ocean Acidification PI Meeting(March 22-24, 2011, Woods Hole, MA)
2nd U.S. Ocean Acidification PI Meeting(Sept. 18-20, 2013, Washington, DC)
3rd U.S. Ocean Acidification PI Meeting (June 9-11, 2015, Woods Hole, MA – Tentative)
NSF media releases for the Ocean Acidification Program:
Press Release 12-179 nsf.gov - National Science Foundation (NSF) News - Ocean Acidification: Finding New Answers Through National Science Foundation Research Grants - US National Science Foundation (NSF)
Press Release 14-116 nsf.gov - National Science Foundation (NSF) News - Ocean Acidification: NSF awards $11.4 million in new grants to study effects on marine ecosystems - US National Science Foundation (NSF)
The Ocean Carbon and Biogeochemistry (OCB) program focuses on the ocean's role as a component of the global Earth system, bringing together research in geochemistry, ocean physics, and ecology that inform on and advance our understanding of ocean biogeochemistry. The overall program goals are to promote, plan, and coordinate collaborative, multidisciplinary research opportunities within the U.S. research community and with international partners. Important OCB-related activities currently include: the Ocean Carbon and Climate Change (OCCC) and the North American Carbon Program (NACP); U.S. contributions to IMBER, SOLAS, CARBOOCEAN; and numerous U.S. single-investigator and medium-size research projects funded by U.S. federal agencies including NASA, NOAA, and NSF.
The scientific mission of OCB is to study the evolving role of the ocean in the global carbon cycle, in the face of environmental variability and change through studies of marine biogeochemical cycles and associated ecosystems.
The overarching OCB science themes include improved understanding and prediction of: 1) oceanic uptake and release of atmospheric CO2 and other greenhouse gases and 2) environmental sensitivities of biogeochemical cycles, marine ecosystems, and interactions between the two.
The OCB Research Priorities (updated January 2012) include: ocean acidification; terrestrial/coastal carbon fluxes and exchanges; climate sensitivities of and change in ecosystem structure and associated impacts on biogeochemical cycles; mesopelagic ecological and biogeochemical interactions; benthic-pelagic feedbacks on biogeochemical cycles; ocean carbon uptake and storage; and expanding low-oxygen conditions in the coastal and open oceans.