Marine Biology Commons^™

Photorespiration In Eelgrass (Zostera Marina L.): A Photoprotection Mechanism For Survival In A Co₂-Limited World, Billur Celebi-Ergin, Richard C. Zimmerman, Victoria J. Hill

OES Faculty Publications

Photorespiration, commonly viewed as a loss in photosynthetic productivity of C3 plants, is expected to decline with increasing atmospheric CO₂, even though photorespiration plays an important role in the oxidative stress responses. This study aimed to quantify the role of photorespiration and alternative photoprotection mechanisms in Zostera marina L. (eelgrass), a carbon-limited marine C3 plant, in response to ocean acidification. Plants were grown in controlled outdoor aquaria at different [CO₂]aq ranging from ~55 (ambient) to ~2121 μM for 13 months and compared for differences in leaf photochemistry by simultaneous measurements of O₂ flux and …

Late Afternoon Seasonal Transition To Dissolution In A Coral Reef: An Early Warning Of A Net Dissolving Ecosystem?, Laura Stoltenberg, Kai G. Schulz, Coulson A. Lantz, Tyler Cyronak, Bradley D. Eyre

Marine & Environmental Sciences Faculty Articles

There are concerns that reefs will transition from net calcifying to net dissolving in the near future due to decreasing calcification and increasing dissolution rates. Here we present in situ rates of net ecosystem calcification (NEC) and net ecosystem production (NEP) on a coral reef flat using a slack-water approach. Up until dusk, the reef was net calcifying in most months but shifted to net dissolution in austral summer, coinciding with high respiration rates and a lower aragonite saturation state (Ω_arag). The estimated sediment contribution to NEC ranged from 8 – 21 % during the day and 45 …

Porewater Carbonate Chemistry Dynamics In A Temperate And A Subtropical Seagrass System, Theodor Kindeberg, Nicholas R. Bates, Travis A. Courtney, Tyler Cyronak, Alyssa Griffin, Fred T. Mackenzie, May-Linn Paulsen, Andreas J. Andersson

Marine & Environmental Sciences Faculty Articles

Seagrass systems are integral components of both local and global carbon cycles and can substantially modify seawater biogeochemistry, which has ecological ramifications. However, the influence of seagrass on porewater biogeochemistry has not been fully described, and the exact role of this marine macrophyte and associated microbial communities in the modification of porewater chemistry remains equivocal. In the present study, carbonate chemistry in the water column and porewater was investigated over diel timescales in contrasting, tidally influenced seagrass systems in Southern California and Bermuda, including vegetated (Zostera marina) and unvegetated biomes (0–16 cm) in Mission Bay, San Diego, USA …

Will Shark Skin Dissolve Under High Co2?, Emily K. Witt

Scientific Communication News

No abstract provided.

Ocean Change Within Shoreline Communities: From Biomechanics To Behaviour And Beyond, Brian Gaylord, Kristina M. Barclay, Brittany M. Jellison, Laura L. Jurgens, Aaron T. Ninokawa, Emily B. Rivest, Lindsey R. Leighton

VIMS Articles

Humans are changing the physical properties of Earth. In marine systems, elevated carbon dioxide concentrations are driving notable shifts in temperature and seawater chemistry. Here, we consider consequences of such perturbations for organism biomechanics and linkages amongst species within communities.In particular,we examine case examples of altered morphologies and material properties, disrupted consumer–prey behaviours, and the potential for modulated positive (i.e. facilitative) interactions amongst taxa, as incurred through increasing ocean acidity and rising temperatures. We focus on intertidal rocky shores of temperate seas as model systems, acknowledging the longstanding role of these communities in deciphering ecological principles. Our survey illustrates the …

Oysters And Eelgrass: Potential Partners In A High Pco2 Ocean, Maya L. Groner, Colleen A. Burge, Ruth Cox, Natalie D. Rivlin, Mo Turner, Kathryn L. Van Alstyne Dr., Sandy Wyllie-Echeverria, John Bucci, Philip Staudigel, Carolyn S. Friedman

Shannon Point Marine Center Faculty Publications

Ocean acidification (OA) threatens calcifying organisms such as the Pacific oyster, Crassostrea gigas. In contrast, eelgrass, Zostera marina, can benefit from the increase in available carbon for photosynthesis found at a lower seawater pH. Seagrasses can remove dissolved inorganic carbon from OA environments, creating local daytime pH refugia. Pacific oysters may improve the health of eelgrass by filtering out pathogens such as Labyrinthula zosterae, which causes eelgrass wasting disease (EWD). Using a laboratory experiment, we found that co-culture of eelgrass with oysters reduced the severity of EWD. EWD was also reduced in more acidic waters, which negatively …

Thresholds And Drivers Of Coral Calcification Responses To Climate Change, Niklas Kornder, Bernhard Riegl, Joana Figueiredo

Marine & Environmental Sciences Faculty Articles

Increased temperature and CO₂ levels are considered key drivers of coral reef degradation. However, individual assessments of ecological responses (calcification) to these stressors are often contradicting. To detect underlying drivers of heterogeneity in coral calcification responses, we developed a procedure for the inclusion of stress–effect relationships in ecological meta‐analyses. We applied this technique to a dataset of 294 empirical observations from 62 peer‐reviewed publications testing individual and combined effects of elevated temperature and pCO₂ on coral calcification. Our results show an additive interaction between warming and acidification, which reduces coral calcification by 20% when pCO₂ levels exceed …

Taking The Metabolic Pulse Of The World's Coral Reefs, Tyler Cyronak, Andreas J. Andersson, Chris Langdon, Rebecca Albright, Nicholas R. Bates, Ken Caldeira, Renee Carlton, Jorge E. Corredor, Rob B. Dunbar, Ian Enochs, Jonathan Erez, Bradley D. Eyre, Jean-Pierre Gattuso, Dwight Gledhill, Hajime Kayanne, David I. Kline, David A. Koweek, Coulson Lantz, Boaz Lazar, Derek Manzello, Ashly Mcmahon, Melissa Melendez, Heather N. Page, Isaac R. Santos, Kai G. Schulz, Emily Shaw, Jacob Silverman, Atsushi Suzuki, Lida Teneva, Atsushi Watanabe, Shoji Yamamoto

Marine & Environmental Sciences Faculty Articles

Worldwide, coral reef ecosystems are experiencing increasing pressure from a variety of anthropogenic perturbations including ocean warming and acidification, increased sedimentation, eutrophication, and overfishing, which could shift reefs to a condition of net calcium carbonate (CaCO3) dissolution and erosion. Herein, we determine the net calcification potential and the relative balance of net organic carbon metabolism (net community production; NCP) and net inorganic carbon metabolism (net community calcification; NCC) within 23 coral reef locations across the globe. In light of these results, we consider the suitability of using these two metrics developed from total alkalinity (TA) and dissolved inorganic carbon (DIC) …

Experimental Impacts Of Climate Warming And Ocean Carbonation On Eelgrass Zostera Marina, Richard C. Zimmerman, Victoria J. Hill, Malee Jinuntuya, Billur Celebi, David Ruble, Miranda Smith, Tiffany Cedeno, W. Mark Swingle

OES Faculty Publications

CO₂ is a critical and potentially limiting substrate for photosynthesis of both terrestrial and aquatic ecosystems. In addition to being a climate-warming greenhouse gas, increasing concentrations of CO₂ will dissolve in the oceans, eliciting both negative and positive responses among organisms in a process commonly known as ocean acidification. The dissolution of CO₂ into ocean surface waters, however, also increases its availability for photosynthesis, to which the highly successful, and ecologically important, seagrasses respond positively. Thus, the process might be more accurately characterized as ocean carbonation. This experiment demonstrated that CO₂ stimulation of primary production enhances …

The Mystery Of Ocean Acidification, Patricia Thibodeau

Reports

Grades: 9-12 Subjects: Biology | Life Science | Environmental Science | Chemistry

This lesson plan invites middle-school students to solve a mystery: what is ocean acidification and how is it affecting marine life in the Antarctic? To solve the mystery, students will participate in an ocean acidification scavenger hunt, and propose hypotheses and arrive at their own conclusions with interpretation of real-time data from the Antarctic.

Antagonistic Effects Of Ocean Acidification And Rising Sea Surface Temperature On The Dissolution Of Coral Reef Carbonate Sediments, Daniel Trnovsky, Laura Stoltenberg, Tyler Cyronak, Bradley D. Eyre

Marine & Environmental Sciences Faculty Articles

Increasing atmospheric CO₂ is raising sea surface temperature (SST) and increasing seawater CO₂ concentrations, resulting in a lower oceanic pH (ocean acidification; OA), which is expected to reduce the accretion of coral reef ecosystems. Although sediments comprise most of the calcium carbonate (CaCO₃) within coral reefs, no in situ studies have looked at the combined effects of increased SST and OA on the dissolution of coral reef CaCO₃ sediments. In situ benthic chamber incubations were used to measure dissolution rates in permeable CaCO₃ sands under future OA and SST scenarios in a coral reef …

Effects Of Elevated Pco2 And Irradiance On Growth, Photosynthesis And Calcification In Halimeda Discoidea, K. E. Peach, M. S. Koch, Patricia Blackwelder

Marine & Environmental Sciences Faculty Articles

Ocean acidification (OA) effects on photophysiology and calcification were examined in Halimeda discoidea, a calcifying macroalga that produces tropical reef sediments. Photosynthetic parameters, including maximum photosynthetic rate (P_max), photosynthetic efficiency (α) and compensating irradiance (I_c) were determined in short-term assays on live thalli after a 10 d exposure to 4 levels of CO₂ partial pressures (pCO₂; 491, 653, 982 and 1201 µatm) under saturating (300 µmol photons m^-2 s^-1) and sub-saturating (90 µmol photons m^-2 s^-1) irradiance in an aquaria study. Morphology …

Understanding Ocean Acidification Impacts On Organismal To Ecological Scales, Andreas J. Andersson, David I. Kline, Peter J. Edmunds, Stephen D. Archer, Nina Bednarsek, Robert C. Carpenter, Meg Chadsey, Philip Goldstein, Andrea G. Grottoli, Thomas P. Hurst, Andrew L. King, Janet E. Kübler, Ilsa B. Kuffner, Katherine R.M. Mackey, Bruce A. Menge, Adina Paytan, Ulf Riebesell, Astrid Schnetzer, Mark E. Warner, Richard C. Zimmerman

OES Faculty Publications

Ocean acidification (OA) research seeks to understand how marine ecosystems and global elemental cycles will respond to changes in seawater carbonate chemistry in combination with other environmental perturbations such as warming, eutrophication, and deoxygenation. Here, we discuss the effectiveness and limitations of current research approaches used to address this goal. A diverse combination of approaches is essential to decipher the consequences of OA to marine organisms, communities, and ecosystems. Consequently, the benefits and limitations of each approach must be considered carefully. Major research challenges involve experimentally addressing the effects of OA in the context of large natural variability in seawater …

Shell Condition And Survival Of Puget Sound Pteropods Are Impaired By Ocean Acidification Conditions, D. Shallin Busch, Michael Maher, Patricia Thibodeau, Paul Mcelhany

VIMS Articles

We tested whether the thecosome pteropod Limacina helicina from Puget Sound, an urbanized estuary in the northwest continental US, experiences shell dissolution and altered mortality rates when exposed to the high CO₂, low aragonite saturation state (Ω_a) conditions that occur in Puget Sound and the northeast Pacific Ocean. Five, week-long experiments were conducted in which we incubated pteropods collected from Puget Sound in four carbon chemistry conditions: current summer surface (∼460–500 µatm CO₂, Ω_a≈1.59), current deep water or surface conditions during upwelling (∼760 and ∼1600–1700 µatm CO₂, Ω_a≈1.17 …

Enhanced Acidification Of Global Coral Reefs Driven By Regional Biogeochemical Feedbacks, Tyler Cyronak, Kai G. Schulz, Isaac R. Santos, Bradley D. Eyre

Marine & Environmental Sciences Faculty Articles

Physical uptake of anthropogenic CO₂ is the dominant driver of ocean acidification (OA) in the open ocean. Due to expected decreases in calcification and increased dissolution of CaCO₃ framework, coral reefs are thought to be highly susceptible to OA. However, biogeochemical processes can influence the pCO₂ and pH of coastal ecosystems on diel and seasonal time scales, potentially modifying the long‐term effects of increasing atmospheric CO₂. By compiling data from the literature and removing the effects of short‐term variability, we show that the average pCO₂ of coral reefs throughout the globe has increased ~3.5‐fold …

Drivers Of Pco2 Variability In Two Contrasting Coral Reef Lagoons: The Influence Of Submarine Groundwater Discharge, Tyler Cyronak, Isaac R. Santos, Dirk V. Erler, Damien T. Maher, Bradley D. Eyre

Marine & Environmental Sciences Faculty Articles

The impact of groundwater on pCO₂ variability was assessed in two coral reef lagoons with distinct drivers of submarine groundwater discharge (SGD). Diel variability of pCO₂ in the two ecosystems was explained by a combination of biological drivers and SGD inputs. In Rarotonga, a South Pacific volcanic island, ²²²Rn‐derived SGD was driven primarily by a steep terrestrial hydraulic gradient, and the water column was influenced by the high pCO₂ (5501 µatm) of the fresh groundwater. In Heron Island, a Great Barrier Reef coral cay, SGD was dominated by seawater recirculation through the sediments …

Permeable Coral Reef Sediment Dissolution Driven By Elevated Pco2 And Pore Water Advection, Tyler Cyronak, Isaac R. Santos, Bradley D. Eyre

Marine & Environmental Sciences Faculty Articles

Ocean acidification (OA) is expected to drive the transition of coral reef ecosystems from net calcium carbonate (CaCO₃) precipitating to net dissolving within the next century. Although permeable sediments represent the largest reservoir of CaCO₃ in coral reefs, the dissolution of shallow CaCO₃ sands under future pCO₂ levels has not been measured under natural conditions. In situ, advective chamber incubations under elevated pCO₂ (~800 µatm) shifted the sediments from net precipitating to net dissolving. Pore water advection more than doubled dissolution rates (1.10 g CaCO₃ m⁻² d⁻¹) when compared to …

Hysteresis Between Coral Reef Calcification And The Seawater Aragonite Saturation State, Ashly Mcmahon, Isaac R. Santos, Tyler Cyronak, Bradley D. Eyre

Marine & Environmental Sciences Faculty Articles

Some predictions of how ocean acidification (OA) will affect coral reefs assume a linear functional relationship between the ambient seawater aragonite saturation state (Ω_a) and net ecosystem calcification (NEC). We quantified NEC in a healthy coral reef lagoon in the Great Barrier Reef during different times of the day. Our observations revealed a diel hysteresis pattern in the NEC versus Ω_a relationship, with peak NEC rates occurring before the Ω_a peak and relatively steady nighttime NEC in spite of variable Ω_a. Net ecosystem production had stronger correlations with NEC than light, temperature, nutrients, pH, …

Meta-Analysis Reveals Complex Marine Biological Responses To The Interactive Effects Of Ocean Acidification And Warming, Ben P. Harvey, Dylan Gwynn-Jones, Philippa J. Moore

Research outputs 2013

Ocean acidification and warming are considered two of the greatest threats to marine biodiversity, yet the combined effect of these stressors on marine organisms remains largely unclear. Using a meta-analytical approach, we assessed the biological responses of marine organisms to the effects of ocean acidification and warming in isolation and combination. As expected biological responses varied across taxonomic groups, life-history stages, and trophic levels, but importantly, combining stressors generally exhibited a stronger biological (either positive or negative) effect. Using a subset of orthogonal studies, we show that four of five of the biological responses measured (calcification, photosynthesis, reproduction, and survival, …

Increased Feeding And Nutrient Excretion Of Adult Antarctic Krill, Euphausia Superba, Exposed To Enhanced Carbon Dioxide (Co2), Gk Saba, O Schofield, Jj Torres, Eh Ombres, Deborah K. Steinberg

VIMS Articles

Ocean acidification has a wide-ranging potential for impacting the physiology and metabolism of zooplankton. Sufficiently elevated CO2 concentrations can alter internal acid-base balance, compromising homeostatic regulation and disrupting internal systems ranging from oxygen transport to ion balance. We assessed feeding and nutrient excretion rates in natural populations of the keystone species Euphausia superba (Antarctic krill) by conducting a CO2 perturbation experiment at ambient and elevated atmospheric CO2 levels in January 2011 along the West Antarctic Peninsula (WAP). Under elevated CO2 conditions (similar to 672 ppm), ingestion rates of krill averaged 78 mu g C individual(-1) d(-1) and were 3.5 times …