| 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 includes rates of photosynthesis and respiration by Ulva during culture experiments grown at 15 degrees C under various pCO2 levels, during May through July 2015.
Related Datasets:
Ulva: Carbonate chemistry pCO2: Carbonate chemistry of Ulva lactuca culture pots testing the effects of pCO2 variability (Seaweed OA Resilience project)
Ulva: Chl a: Chlorophyll a per unit biomass in Ulva lactuca under ocean acidification (OA) conditions (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: seawater delta13C: Stable isotope ratio and concentration of carbon in seawater from Ulva OA experiments (Seaweed OA Resilience project)
Measurements of photosynthesis and respiration of Ulva lactuca occurred at the end of 3 weeks of acclimation to various levels of ocean acidification at 15°C. Small circular sections of U. lactuca thalli used for measurements were sampled with a cork borer the evening before measurement and returned to culture conditions overnight to allow for wound healing. Plant sections used to estimate rates of photosynthesis and respiration from oxygen exchange measurements were placed in small white, mesh threaded bags designed to fit the diameter of the cuvette chamber so that the plant material was oriented perpendicularly to the light source provided in the Qubit Systems Dissolved Oxygen package. Prior to introducing plants to the cuvette chamber, oxygen exchange between the stirred seawater and electrode system (i.e., oxygen consumption by the electrode) was monitored to adjust for its effect on subsequent measurements in the presence of plant material. Sections were transferred to the cuvette containing a magnetic stirring bar and 3 ml of seawater corresponding to the average pCO2 level in their particular culture pot and placed in darkness for 10-15 minutes prior to beginning measurement. Once measurements began, output of oxygen exchange was monitored until a steady state of oxygen exchange was attained (typically within 10 minutes) in either darkness or light. Photosynthesis and respiration were measured at 15°C and ~550, and 0, µmole photons m-2 s-1, respectively; the same temperature and light conditions as in growth culture. Respiration was measured both following a ≥10 minute acclimation period in darkness prior to light exposure (dark respiration) and again in darkness immediately following exposure to the saturating light intensity (as an estimate of respiration that occurs in the light). Following these measurements in seawater at their culture pCO2 level, the seawater in the cuvette was replaced with standard air-saturated seawater at 15°C and the measurement process described above was repeated for measurements of respiration in the dark and ‘light’ and photosynthesis. After measurements of gas exchange, the mass of plant tissue was measured on an analytical balance.
Note: Trial 1 was a pilot test of culture system and methodological procedures so was not used for data collection.
BCO-DMO Processing Notes:
- added a conventional header with dataset name and description, PI names, version date
| File |
|---|
Ulva_PS_Resp_Cult_AirSat.csv (Comma Separated Values (.csv), 9.27 KB) MD5:8ab5ddbe21978320411395180abf4aa5 Primary data file for dataset ID 732625 |
| Parameter | Description | Units |
| Label | sample identifier formatted as: trial-culture pot.plant replicate numbers | unitless |
| pCO2_avg | Average pCO2 partial pressure in seawater tanks | microatmospheres (µatm) |
| pCO2_sd | Variability of pCO2 partial pressure - standard deviation | microatmospheres (µatm) |
| Off1C | slope of oxygen exchange during first dark period in pCO2 culture seawater | milligrams O2/liter/second (mg L-1 s-1) |
| OnC | slope of oxygen exchange during light period in pCO2 culture seawater | milligrams O2/liter/second (mg L-1 s-1) |
| Off2C | slope of oxygen exchange during second dark period in pCO2 culture seawater | milligrams O2/liter/second (mg L-1 s-1) |
| Off1A | slope of oxygen exchange during first dark period in aerated standard seawater | milligrams O2/liter/second (mg L-1 s-1) |
| OnA | slope of oxygen exchange during light period in aerated standard seawater | milligrams O2/liter/second (mg L-1 s-1) |
| Off2A | slope of oxygen exchange during second dark period in aerated standard seawater | milligrams O2/liter/second (mg L-1 s-1) |
| Fresh_Weight | Mass of tissue sample | grams |
| DRespC | Dark respiration rate during first dark period in pCO2 culture seawater | mol O2/g/min NA |
| PmaxC | Maximum rate of photosynthesis in pCO2 culture seawater | mol O2/g/min NA |
| LRespC | Estimated respiration in the light in pCO2 culture seawater | mol O2/g/min NA |
| DRespA | Dark respiration rate during first dark period in aerated standard seawater | mol O2/g/min NA |
| PmaxA | Maximum rate of photosynthesis in aerated standard seawater | mol O2/g/min NA |
| LRespA | Estimated respiration in the light in aerated standard seawater | mol O2/g/min NA |
| Dataset-specific Instrument Name | Qubit Systems Dissolved Oxygen package (Q-box OX1LP) |
| Generic Instrument Name | Oxygen Sensor |
| Dataset-specific Description | Used to measure oxygen, photosynthesis, and respiration.
http://www.qubitbiology.com/ox1lp-dissolved-oxygen/ |
| Generic Instrument Description | An electronic device that measures the proportion of oxygen (O2) in the gas or liquid being analyzed |
| Dataset-specific Instrument Name | Mettler Toledo AG204 Delta Range Analytical Balance |
| Generic Instrument Name | scale |
| Generic Instrument Description | An instrument used to measure weight or mass. |
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) |