| Contributors | Affiliation | Role |
|---|---|---|
| Kubler, Janet E. | California State University Northridge (CSUN) | Principal Investigator |
| Dudgeon, Steve | California State University Northridge (CSUN) | Co-Principal Investigator |
| Copley, Nancy | Woods Hole Oceanographic Institution (WHOI BCO-DMO) | BCO-DMO Data Manager |
This dataset reports the chlorophyll a concentration per unit biomass of Ulva lactuca grown in closed culture pots at varying pCO2 levels.
Related Datasets:
Ulva: Carbonate chemistry pCO2: Carbonate chemistry of Ulva lactuca culture pots testing the effects of pCO2 variability (Seaweed OA Resilience project)
Ulva: CHN and stable isotopes: Stable isotope ratios and mass of carbon and nitrogen in Ulva cells under ocean acidification conditions (Seaweed OA Resilience project)
Ulva: Growth: Growth rates of Ulva exposed to different average and variability of pCO2 (Seaweed OA Resilience project)
Ulva: pH and temperature time-series: Time-series at 10 minute sampling interval of pH and temperature in Ulva culture pots (Seaweed OA Resilience project)
Ulva: pH Drift: Carbonate chemistry over a time course with Ulva in pH drift experiments (Seaweed OA Resilience project)
Ulva: Photosynthesis and respiration: Rates of photosynthesis and respiration by Ulva exposed to different average and variability of pCO2 (Seaweed OA Resilience project)
Ulva: seawater delta13C: Stable isotope ratio and concentration of carbon in seawater from Ulva OA experiments (Seaweed OA Resilience project)
Culture pots were placed in large thermally insulated coolers in a temperature-controlled water bath at 15° C under saturating illumination of ~550 µmoles photons/m^2/s on a 12:12 L:D cycle. pCO2 treatments were supplied to closed culture pots by use of a gas mixing system combining nitrogen, oxygen and carbon dioxide to specific CO2 partial pressures, 20.9% oxygen and the balance being nitrogen.
Chlorophyll a was extracted from Ulva tissue following the procedure described in Duncan and Harrison (1982). Chlorophyll a concentrations were measured using a Shimadzu UV-2450 UV-visible spectrophotometer.
BCO-DMO Processing Notes:
- added a conventional header with dataset name and description, PI names, version date
- modified parameter names to conform with BCO-DMO naming conventions
| File |
|---|
Chl_a_Ulva.csv (Comma Separated Values (.csv), 6.06 KB) MD5:13302458522a7c50790cb4247dfd48f0 Primary data file for dataset ID 732438 |
| Parameter | Description | Units |
| Label | Trial number-pot number.frozen tissue replicate | unitless |
| pCO2_avg | Average pCO2 partial pressure in seawater tanks | microatmospheres (µatm) |
| pCO2_sd | Variability of pCO2 partial pressure - standard deviation | microatmospheres (µatm) |
| Fresh_Wt | Fresh weight of tissue sample prior to deep freeze | grams |
| DMSO_A665 | Absorbance of light by ground Ulva tissue at 665nm in 1.25 ml of an 80% DMSO solution in water | unitless |
| Methanol_A668 | Absorbance of light by ground Ulva tissue at 668nm in 6 ml methanol | unitless |
| Methanol_A635 | Absorbance of light by ground Ulva tissue at 635nm in 6 ml methanol | unitless |
| DMSO_ext | Chlorophyll a extracted in DMSO | milligram/liter (mg/L) |
| Meth_ext | Chlorophyll a in pooled extracts of 12 ml of methanol | milligram/liter (mg/L) |
| Total_chl_mg | Total chlorophyll a extracted from ground tissue | milligrams (mg) |
| chl_a | Chlorophyll a concentration per unit biomass | milligrams/gram (mg/g) |
| Dataset-specific Instrument Name | Shimadzu UV-2450 UV-visible spectrophotometer |
| Generic Instrument Name | UV Spectrophotometer-Shimadzu |
| Dataset-specific Description | Used to measure chlorophyll a concentration. |
| Generic Instrument Description | The Shimadzu UV Spectrophotometer is manufactured by Shimadzu Scientific Instruments (ssi.shimadzu.com). Shimadzu manufacturers several models of spectrophotometer; refer to dataset for make/model information. |
Benthic macroalgae contribute to intensely productive near shore ecosystems and little is known about the potential effects of ocean acidification on non-calcifying macroalgae. Kübler and Dudgeon will test hypotheses about two macroalgae, Ulva spp. and Plocamium cartilagineum, which, for different reasons, are hypothesized to be more productive and undergo ecological expansions under predicted changes in ocean chemistry. They have designed laboratory culture-based experiments to quantify the scope for response to ocean acidification in Plocamium, which relies solely on diffusive uptake of CO2, and populations of Ulva spp., which have an inducible concentrating mechanism (CCM). The investigators will culture these algae in media equilibrated at 8 different pCO2 levels ranging from 380 to 940 ppm to address three key hypotheses. The first is that macroalgae (such as Plocamium cartilagineum) that are not able to acquire inorganic carbon in changed form will benefit, in terms of photosynthetic and growth rates, from ocean acidification. There is little existing data to support this common assumption. The second hypothesis is that enhanced growth of Ulva sp. under OA will result from the energetic savings from down regulating the CCM, rather than from enhanced photosynthesis per se. Their approach will detect existing genetic variation for adaptive plasticity. The third key hypothesis to be addressed in short-term culture experiments is that there will be a significant interaction between ocean acidification and nitrogen limited growth of Ulva spp., which are indicator species of eutrophication. Kübler and Dudgeon will be able to quantify the individual effects of ocean acidification and nitrogenous nutrient addition on Ulva spp. and also, the synergistic effects, which will inevitably apply in many highly productive, shallow coastal areas. The three hypotheses being addressed have been broadly identified as urgent needs in our growing understanding of the impacts of ocean acidification.
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.
PI Meetings:
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 10-186 NSF Awards Grants to Study Effects of Ocean Acidification
Discovery Blue Mussels "Hang On" Along Rocky Shores: For How Long?
Press Release 13-102 World Oceans Month Brings Mixed News for Oysters
| Funding Source | Award |
|---|---|
| NSF Division of Ocean Sciences (NSF OCE) |