scholarly journals Effect of excessive CO2 on physiological functions in coastal diatom

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Feng-Jiao Liu ◽  
Shun-Xing Li ◽  
Bang-Qin Huang ◽  
Feng-Ying Zheng ◽  
Xu-Guang Huang
Keyword(s):  
Climate Change ◽  
Ocean Acidification ◽  
Cell Density ◽  
Algal Biomass ◽  
Nutritional Value ◽  
Significant Negative Correlation ◽  
Physiological Functions ◽  
Coastal Phytoplankton ◽  
Influence Of Ph ◽  
Photosynthesis And Respiration

Abstract Rising dissolution of anthropogenic CO2 in seawater may directly/indirectly cause ocean acidification and desalination. However, little is known about coastal physiological functions sensitivity to these processes. Here we show some links between ocean acidification/desalination and physiological functions in Thalassiosira weissflogii. Cell density (CD), protein, chlorophyll a (Chl a), malonaldehyde (MDA), superoxide dismutase (SOD), and carbonic anhydrase (CAs) were determined for the assessment of algal biomass, nutritional value, photosynthesis and respiration, lipid peroxidation, antioxidant capacity, and carbon sequestration ability. The influence of pH on the algal Chl a and MDA were extremely significant (P < 0.01). Salinity (S) on cell density and acidity (pH) on protein was significant (0.01 < P < 0.05). Additionally, a significant negative-correlation was observed between cell density and CAs. CAs and SOD had negatively correlations with CD, Chl a, protein, and MDA under pH or S influence, but positive correlation between themselves. Coastal physiological functions were affected by increasing order was acidification < acidification + desalination < desalination for Chl a and protein, desalination < acidification + desalination < acidification for SOD and CAs. Thus, the ongoing excessive CO2-driven ocean acidification and desalination should be of high attention when assessing the risks of climate change on coastal phytoplankton.

scholarly journals Effect of environmental history on the habitat-forming kelp Macrocystis pyrifera responses to ocean acidification and warming: a physiological and molecular approach

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pamela A. Fernández ◽  
Jorge M. Navarro ◽  
Carolina Camus ◽  
Rodrigo Torres ◽  
Alejandro H. Buschmann
Keyword(s):  
Climate Change ◽  
Ocean Acidification ◽  
Environmental History ◽  
Coastal Upwelling ◽  
Macrocystis Pyrifera ◽  
Natural Variability ◽  
Kelp Forests ◽  
Species Response ◽  
Enhanced Expression ◽  
Mesocosm Experiments

AbstractThe capacity of marine organisms to adapt and/or acclimate to climate change might differ among distinct populations, depending on their local environmental history and phenotypic plasticity. Kelp forests create some of the most productive habitats in the world, but globally, many populations have been negatively impacted by multiple anthropogenic stressors. Here, we compare the physiological and molecular responses to ocean acidification (OA) and warming (OW) of two populations of the giant kelp Macrocystis pyrifera from distinct upwelling conditions (weak vs strong). Using laboratory mesocosm experiments, we found that juvenile Macrocystis sporophyte responses to OW and OA did not differ among populations: elevated temperature reduced growth while OA had no effect on growth and photosynthesis. However, we observed higher growth rates and NO3− assimilation, and enhanced expression of metabolic-genes involved in the NO3− and CO2 assimilation in individuals from the strong upwelling site. Our results suggest that despite no inter-population differences in response to OA and OW, intrinsic differences among populations might be related to their natural variability in CO2, NO3− and seawater temperatures driven by coastal upwelling. Further work including additional populations and fluctuating climate change conditions rather than static values are needed to precisely determine how natural variability in environmental conditions might influence a species’ response to climate change.

scholarly journals Ocean Acidification Amplifies the Olfactory Response to 2-Phenylethylamine: Altered Cue Reception as a Mechanistic Pathway?

2021 ◽  
Author(s):  
Paula Schirrmacher ◽  
Christina C. Roggatz ◽  
David M. Benoit ◽  
Jörg D. Hardege
Keyword(s):  
Climate Change ◽  
Ocean Acidification ◽  
Hermit Crabs ◽  
Ecological Interactions ◽  
Ecological Processes ◽  
Mechanistic Pathway ◽  
Sea Lampreys ◽  
Pagurus Bernhardus ◽  
Decreasing Ph ◽  
The Impact

AbstractWith carbon dioxide (CO2) levels rising dramatically, climate change threatens marine environments. Due to increasing CO2 concentrations in the ocean, pH levels are expected to drop by 0.4 units by the end of the century. There is an urgent need to understand the impact of ocean acidification on chemical-ecological processes. To date, the extent and mechanisms by which the decreasing ocean pH influences chemical communication are unclear. Combining behaviour assays with computational chemistry, we explore the function of the predator related cue 2-phenylethylamine (PEA) for hermit crabs (Pagurus bernhardus) in current and end-of-the-century oceanic pH. Living in intertidal environments, hermit crabs face large pH fluctuations in their current habitat in addition to climate-change related ocean acidification. We demonstrate that the dietary predator cue PEA for mammals and sea lampreys is an attractant for hermit crabs, with the potency of the cue increasing with decreasing pH levels. In order to explain this increased potency, we assess changes to PEA’s conformational and charge-related properties as one potential mechanistic pathway. Using quantum chemical calculations validated by NMR spectroscopy, we characterise the different protonation states of PEA in water. We show how protonation of PEA could affect receptor-ligand binding, using a possible model receptor for PEA (human TAAR1). Investigating potential mechanisms of pH-dependent effects on olfactory perception of PEA and the respective behavioural response, our study advances the understanding of how ocean acidification interferes with the sense of smell and thereby might impact essential ecological interactions in marine ecosystems.

scholarly journals Rhodoliths in Brazil: Current knowledge and potential impacts of climate change

2016 ◽  
Vol 64 (spe2) ◽  
pp. 117-136 ◽  
Author(s):  
Paulo Antunes Horta ◽  
Pablo Riul ◽  
Gilberto M. Amado Filho ◽  
Carlos Frederico D. Gurgel ◽  
Flávio Berchez ◽  
...  
Keyword(s):  
Climate Change ◽  
Global Change ◽  
Ocean Acidification ◽  
Heat Waves ◽  
Current Knowledge ◽  
Coastal Pollution ◽  
Brazil Current ◽  
Run Off ◽  
Benthic Ecosystems ◽  
Impacts Of Climate Change

Abstract Rhodolith beds are important marine benthic ecosystems, representing oases of high biodiversity among sedimentary seabed environments. They are found frequently and abundantly, acting as major carbonate 'factories' and playing a key role in the biogeochemical cycling of carbonates in the South Atlantic. Rhodoliths are under threat due to global change (mainly related to ocean acidification and global warming) and local stressors, such as fishing and coastal run-off. Here, we review different aspects of the biology of these organisms, highlighting the predicted effects of global change, considering the additional impact of local stressors. Ocean acidification (OA) represents a particular threat that can reduce calcification or even promote the decalcification of these bioengineers, thus increasing the eco-physiological imbalance between calcareous and fleshy algae. OA should be considered, but this together with extreme events such as heat waves and storms, as main stressors of these ecosystems at the present time, will worsen in the future, especially if possible interactions with local stressors like coastal pollution are taken into consideration. Thus, in Brazil there is a serious need for starting monitoring programs and promote innovative experimental infrastructure in order to improve our knowledge of these rich environments, optimize management efforts and enhance the needed conservation initiatives.

scholarly journals Governing the global commons: an ethical-legal framework

2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Prue Taylor
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Land Use Change ◽  
Ocean Acidification ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Legal Framework ◽  
State System ◽  
Global Commons ◽  
Global Challenges

Governance of the Earth’s global ecological commons creates unprecedented challenges for humanity. Our traditional Westphalian state system was not designed to respond to these global challenges and thus far it has failed to transform. Climate change is the current headline issue; 30 years on and we still swing between hope and despair about our collective ability to radically reduce greenhouse gas emissions. Related issues are beginning to vie for our response: ocean acidification, mass species extinction, land use change and freshwater scarcity. 

Tree growth and drought impact the dynamics of C allocation and change the coupling between photosynthesis and respiration in stem and soil

2021 ◽  
Author(s):  
Yu Tang ◽  
Pauliina Schiestl-Aalto ◽  
Kira Ryhti ◽  
Liisa Kulmala ◽  
Elina Sahlstedt ◽  
...  
Keyword(s):  
Climate Change ◽  
Growing Season ◽  
Forest Growth ◽  
Time Lags ◽  
Dry Period ◽  
Organ Growth ◽  
Substrate Concentrations ◽  
Photosynthesis And Respiration ◽  
Whole Tree ◽  
Tree Organ

&lt;p&gt;In-depth knowledge about carbon (C) flows within trees and from the trees to forest ecosystem via respiration is essential for accurate modeling of tree growth and C balance. However, significant gaps still exist in our understanding about how trees allocate C for growth and respiration of different tree organs, which makes it difficult to predict the response of forest growth to climate change. A powerful tool to study C allocation within trees is stable C isotope ratio (the ratio of &lt;sup&gt;13&lt;/sup&gt;C to &lt;sup&gt;12&lt;/sup&gt;C relative to a reference, noted as &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C), as this signal is passed from C sources to C sinks with isotopic fractionation along the pathway. In this study, we monitored the &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C signal of CO&lt;sub&gt;2&lt;/sub&gt; fluxes of shoot (A&lt;sub&gt;canopy&lt;/sub&gt;), stem (R&lt;sub&gt;stem&lt;/sub&gt;) and soil (R&lt;sub&gt;soil&lt;/sub&gt;) in a Scots pine (Pinus sylvestris L.) dominated boreal forest in southern Finland for summer 2018, which included a month-long dry period. We also traced the growth of current-year shoots, needles, stem, and fine roots (fibrous and pioneer roots) and the concentrations and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of putative substrates (sugars and starch) in phloem and roots of Scots pine over the growing season. We calculated the correlations between substrate concentrations and respiration fluxes, as well as the correlations between &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of A&lt;sub&gt;canopy&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of R&lt;sub&gt;soil&lt;/sub&gt; or &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of R&lt;sub&gt;stem&lt;/sub&gt; with varying time lags from 3 d to 14 d for different tree organ growth periods and the dry period. We found tight couplings between photosynthesis and respiration, when newly assimilated sugars were allocated to stem or roots for growth or for drought response. These couplings include: 1) a synchrony between fibrous root growth and the concentrations of bulk sugars and starch in roots, associated with increases in R&lt;sub&gt;soil&lt;/sub&gt; under high root substrate concentrations; 2) promoted nighttime R&lt;sub&gt;stem&lt;/sub&gt; under high substrate supply to stem, which is seen as increased phloem glucose to sucrose ratio; 3) shorter time lags between &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of A&lt;sub&gt;canopy&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of R&lt;sub&gt;stem&lt;/sub&gt; under higher stem growth demands; 4) shorter time lags between &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of A&lt;sub&gt;canopy&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of R&lt;sub&gt;soil&lt;/sub&gt; under drought stress than with no water stress. The time lags between &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of A&lt;sub&gt;canopy&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of R&lt;sub&gt;soil&lt;/sub&gt; or &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C of R&lt;sub&gt;stem&lt;/sub&gt; being not uniform further implies that tree C allocation patterns are dynamic over the growing season. In addition, the C allocation to stem and roots occurred after full expansion of current-year shoots or needles, reflecting a whole tree C allocation strategy for growth demands of different tree organs, which prioritizes the demands of source organs. We suggest that the dynamics of C allocation in response to tree organ growth and drought stress should be considered in whole tree C allocation models for projecting forest growth under climate change.&lt;/p&gt;

5. Climate change impacts

2021 ◽  
pp. 64-89
Author(s):  
Mark Maslin
Keyword(s):  
Climate Change ◽  
Health Policy ◽  
Ocean Acidification ◽  
Human Health ◽  
Extreme Events ◽  
Climate Change Impacts ◽  
Climate Science ◽  
Policy Makers ◽  
Shifting Baseline ◽  
Dangerous Climate Change

‘Climate change impacts’ assesses the potential impacts of climate change and how these alter in scale and intensity with increasing warming by breaking down the potential impacts into sectors: extreme heat and droughts, storms and floods, agriculture, ocean acidification, biodiversity, and human health. Policy-makers should identify what dangerous climate change is. We need a realistic target concerning the degree of climate change with which we can cope. Fortunately, the societal coping range is flexible and can change with the shifting baseline and the more frequent extreme events—as long as there is strong climate science to provide clear guidance on what sort of changes are going to occur.

Ocean acidification increases domoic acid contents during a spring to summer succession of coastal phytoplankton

Harmful Algae ◽  
2020 ◽  
Vol 92 ◽  
pp. 101697
Author(s):  
Sylke Wohlrab ◽  
Uwe John ◽  
Kerstin Klemm ◽  
Tim Eberlein ◽  
Anna Maria Forsberg Grivogiannis ◽  
...  
Keyword(s):  
Ocean Acidification ◽  
Domoic Acid ◽  
Coastal Phytoplankton
Sign in / Sign up

Export Citation Format

Share Document