cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.1594/pangaea.939406
title: Seawater carbonate chemistry and specific growth rate, respiration rate, net photosynthetic rate and photochemical parameters of Phaeodactylum tricornutum

description: Experimentally elevated pCO2 and the associated pH drop are known to differentially affect many aspects of the physiology of diatoms under different environmental conditions or in different regions. However, contrasting responses to elevated pCO2 in the dark and light periods of a diel cycle have not been documented. By growing the model diatom Phaeodactylum tricornutum under 3 light levels and 2 different CO2 concentrations, we found that the elevated pCO2/pH drop projected for future ocean acidification reduced the diatom's growth rate by 8–25% during the night period but increased it by up to 9–21% in the light period, resulting in insignificant changes in growth over the diel cycle under the three different light levels. The elevated pCO2 increased the respiration rates irrespective of growth light levels and light or dark periods and enhanced its photosynthetic performance during daytime. With prolonged exposure to complete darkness, simulating the sinking process in the dark zones of the ocean, the growth rates decreased faster under elevated pCO2, along with a faster decline in quantum yield and cell size. Our results suggest that elevated pCO2 enhances the diatom's respiratory energy supplies to cope with acidic stress during the night period but enhances its death rate when the cells sink to dark regions of the oceans below the photic zone, with implications for a possible acidification-induced reduction in vertical transport of organic carbon.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2021-12-15.
DOI: 10.1594/pangaea.944506
title: Radar reflectivities at 94 GHz and microwave brightness temperature measurements at 89 GHz during the AFLUX Arctic airborne campaign in spring 2019 out of Svalbard

description: The published data set consists of measurements performed by the active cloud radar as part of the MiRAC (Microwave Radar and radiometer for Arctic Clouds) operated on board the Polar 5 research aircraft during 14 flights of the Airborne measurements of radiative and turbulent FLUXes of energy and momentum in the Arctic boundary layer (AFLUX) campaign, carried out in spring 2019 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of radar reflectivities of the FMCW 94 GHz cloud radar transformed to nadir view as well brightness temperature measurements at 89 GHz with a 25 deg backwards inclination with respect to the aircrafts fuselage. It should be considerd, that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality checked and is available in netcdf format for each flight separately.Details on the instrument can be found in Mech et al. (2019).
description: The files contain radar reflectivities, brightness temperatures, measurement times, flags for the filters applied, and some key numbers of the operated instrument. In addition, meta information and attributes are provided. The files are in netcdf format following CF-1.8.
DOI: 10.1594/pangaea.807750
title: Hydrochemistry measured on water bottle samples during Hakurei-Maru cruise NH95-2
DOI: 10.1594/pangaea.951403
title: Seawater carbonate chemistry and overall composition of the secondary metabolites of a Predatory Marine Gastropod

description: Water temperature is a major abiotic driver, controlling the rates and nature of biochemical reactions and subsequently affecting the physiology of marine organisms. However, relatively little is known about the implications of heat stress or predicted ocean climate change on marine secondary metabolites. The predatory gastropod Dicathais orbita is a useful model organism for climate change and natural product studies. Here we determine the upper thermal limit (CTMax) of D. orbita and investigate the effects of thermal stress on the bioactive compounds stored in their biosynthetic organ, the hypobranchial gland. Two CTMax experiments were undertaken, along with a static heat stress experiment where whelks were exposed to an elevated temperature of 30°C for one week, compared to a 20°C seawater control. An additional 35-day ocean climate change experiment used combinations of temperature (ambient: 23°C and future: 25°C) and pCO2 (ambient: ~380 ppm and future: ~765 ppm). The impacts on secondary metabolites in all experiments were assessed using liquid chromatography-mass spectrometry. The mean CTMax of the whelks, from the northern limit of their distribution, was found to be 35.2°C using a rapid temperature increase rate of 1°C/1 h, but was only 30.6°C when a gradual heating rate of 1°C/12 h was used. The overall composition of the secondary metabolites was significantly affected by heat stress in all four experiments, but not by elevated pCO2 in the ocean climate change experiment. The proportion of the choline ester murexine was significantly reduced in heat-stressed snails compared to the controls. Tyrindoxyl sulphate was significantly reduced under prolonged exposure to future temperature, whereas the relative abundance of the oxidation product, 6-bromoisatin significantly increased with elevated temperature exposure. Despite the fact that intertidal gastropods like D. orbita might be able to buffer the impact of external temperatures within the predicted future range, this study provides evidence that ocean warming could have significant implications for secondary metabolite production and/or storage in marine invertebrates. Impacts on bioactive molecules with multifunctional ecological roles could have implications for predator populations with possible flow on effects in some marine communities.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2022-11-30.
DOI: 10.1594/pangaea.951362
title: Seawater carbonate chemistry in experiment 1 and 2

description: Acidification-induced changes in neurological function have been documented in several tropical marine fishes. Here, we investigate whether similar patterns of neurological impacts are observed in a temperate Pacific fish that naturally experiences regular and often large shifts in environmental pH/pCO2. In two laboratory experiments, we tested the effect of acidification, as well as pH/pCO2 variability, on gene expression in the brain tissue of a common temperate kelp forest/estuarine fish, Embiotoca jacksoni. Experiment 1 employed static pH treatments (target pH = 7.85/7.30), while Experiment 2 incorporated two variable treatments that oscillated around corresponding static treatments with the same mean (target pH = 7.85/7.70) in an eight-day cycle (amplitude ± 0.15). We found that patterns of global gene expression differed across pH level treatments. Additionally, we identified differential expression of specific genes and enrichment of specific gene sets (GSEA) in comparisons of static pH treatments and in comparisons of static and variable pH treatments of the same mean pH. Importantly, we found that pH/pCO2 variability decreased the number of differentially expressed genes detected between high and low pH treatments, and that inter-individual variability in gene expression was greater in variable treatments than static treatments. These results provide important confirmation of neurological impacts of acidification in a temperate fish species and, critically, that natural environmental variability may mediate the impacts of ocean acidification.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2022-11-30.
DOI: 10.1594/pangaea.950764
title: Seawater carbonate chemistry and survival in Corophium volutator

description: Ocean acidification (OA) may alter the behaviour of sediment-bound metals, modifying their bioavailability and thus toxicity. We provide the first experimental test of this hypothesis with the amphipod Corophium volutator. Amphipods were exposed to two test sediments, one with relatively high metals concentrations (sigma metals 239 mg/kg) and a reference sediment with lower contamination (sigma metals 82 mg/kg) under conditions that mimic current and projected conditions of OA (390 to 1140 μatm pCO2). Survival and DNA damage was measured in the amphipods, while the flux of labile metals was measured in the sediment and water column using Diffusive Gradients in Thin-films. The contaminated sediments became more acutely toxic to C. volutator under elevated pCO2 (1140 μatm). There was also a 2.7-fold increase in DNA damage in amphipods exposed to the contaminated sediment at 750 μatm pCO2, as well as increased DNA-damage in organisms exposed to the reference sediment, but only at 1140 μatm pCO2. The projected pCO2 concentrations increased the flux of nickel (Ni) and zinc (Zn) to labile states in the water column and pore water. However, the increase in metal flux at elevated pCO2 was equal between the reference and contaminated sediments or, occasionally, greater from reference sediments. Hence, the toxicological interaction between OA and contaminants could not be explained by effects of pH on metal speciation. We propose that the additive physiological effects of OA and contaminants will be more important than changes in metal speciation in determining the responses of benthos to contaminated sediments under OA. Our data demonstrate clear potential for near-future OA to increase the susceptibility of benthic ecosystems to contaminants. Environmental policy should consider contaminants within the context of changing environmental conditions. Specifically, sediment metals guidelines may need to be re-evaluated to afford appropriate environmental protection under future conditions of OA.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2022-11-15.
DOI: 10.1594/pangaea.846021
title: Biogeochemical variations in the gulf of Trieste, Italy (2011-2013)

description: The carbonate chemistry and primary and secondary production were studied in an area of freshwater discharge form the Isonzo river in the gulf of Trieste (Northern Adriatic Sea) during 12 cruises carried out from March 2011- February 2013 in the framework of the FP7 MEDSEA (Mediterranean Sea Acidification in a Changing Climate) Project.
DOI: 10.1594/pangaea.953329
title: Seawater carbonate chemistry and survival, size and gene expression in larvae and post-larvae of the sand dollar Dendraster excentricus

description: Seawater temperature, oxygen, salinity and pH are important abiotic factors, changes in which can generate stress in marine organisms. Subtidal and intertidal species, such as the sand dollar Dendraster excentricus, are daily exposed to stressors against which they have developed survival mechanisms to face environmental challenges. Analysing the expression of some key genes in response to stress factors due to changes in temperature and pH, especially in the early stages of development, opens a window of knowledge on the effect that these stressors have on benthos marine organisms. In the present work larvae and post-larvae of D. excentricus were exposed to high temperature and low pH scenarios. Survival, size and gene expression of five genes, involved in both stress response (hsp70 IV and hsp90 beta-like) and biomineralization for skeletogenesis (sm29, sm30A, carbonic anhydrase 14-like and mitochondrial proton/calcium exchanger protein LOC575637), were analysed in 4-, 6-, 8-arms, competent larvae and post-larvae. Survival of stressed larvae and post-larvae presented a significant decrease, up to 37% in some stages. A size reduction of almost 30 μm was observed when larvae were exposed to stressful conditions, except in competent larvae and in post-larvae where no significant changes were detected. After stress treatments, transcripts of hsp90 beta-like were up-regulated in all larval stages but hsp70 IV transcripts were not. Under tested stressful conditions sm29 and sm30A expression was down-regulated in larvae and post-larvae, while carbonic anhydrase 14-like and LOC575637 expressions were up-regulated. It is evident that tolerance to changes in seawater temperature and pH has a direct effect on metabolic functions of D. excentricus larvae and post-larvae, which depends on the developmental stage. If laboratory results are extrapolated to marine ecosystems, it is possible that populations of this structuring organism may be disturbed with subsequent damage to ecosystem balance, until resilient organisms acclimatize and adapt to their changing habitats.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2023-01-05.
DOI: 10.1594/pangaea.908309
title: Seawater carbonate chemistry and hardness and stiffness of the Portuguese oyster shell

description: The rapidly intensifying process of ocean acidification (OA) due to anthropogenic CO2 is not only depleting carbonate ions necessary for calcification but also causing acidosis and disrupting internal pH homeostasis in several marine organisms. These negative consequences of OA on marine calcifiers, i.e. oyster species, have been very well documented in recent studies; however, the consequences of reduced or impaired calcification on the end-product, shells or skeletons, still remain one of the major research gaps. Shells produced by marine organisms under OA are expected to show signs of dissolution, disorganized microstructure and reduced mechanical properties. To bridge this knowledge gap and to test the above hypothesis, we investigated the effect of OA on juvenile shells of the commercially important oyster species, Magallana angulata, at ecologically and climatically relevant OA levels (using pH 8.1, 7.8, 7.5, 7.2). In lower pH conditions, a drop of shell hardness and stiffness was revealed by nanoindentation tests, while an evident porous internal microstructure was detected by scanning electron microscopy. Crystallographic orientation, on the other hand, showed no significant difference with decreasing pH using electron back-scattered diffraction (EBSD). These results indicate the porous internal microstructure may be the cause of the reduction in shell hardness and stiffness. The overall decrease of shell density observed from micro-computed tomography analysis indicates the porous internal microstructure may run through the shell, thus inevitably limiting the effectiveness of the shell's defensive function. This study shows the potential deterioration of oyster shells induced by OA, especially in their early life stage. This knowledge is critical to estimate the survival and production of edible oysters in the future ocean.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2019-11-08.
description: Supplement to: Meng, Yuan; Guo, Zhenbin; Fitzer, Susan C; Upadhyay, Abhishek; Chan, Vera B S; Li, Chaoyi; Cusack, Maggie; Yao, Haimin; Yeung, Kelvin W K; Thiyagarajan, Vengatesen (2018): Ocean acidification reduces hardness and stiffness of the Portuguese oyster shell with impaired microstructure: a hierarchical analysis. Biogeosciences, 15(22), 6833-6846
DOI: 10.1594/pangaea.953365
title: Seawater carbonate chemistry and phytoplankton productivity between coastal and offshore surface waters in the Taiwan Strait and the South China Sea

description: Seawater acidification (SA) has been documented to either inhibit, enhance, or result in no effect on marine primary productivity (PP). In order to examine the effects of SA in changing environments, we investigated the influences of SA (a decrease of 0.4 pHtotal units with corresponding CO2 concentrations in the range of 22.0–39.7 µM) on PP through deck-incubation experiments at 101 stations in the Taiwan Strait and the South China Sea, including the continental shelf and slope, as well as the deep-water basin. The daily primary productivities in surface seawater under incident solar radiation ranged from 17–306 µg C/µg Chl a/d, with the responses of PP to SA being region-dependent and the SA-induced changes varying from −88 % (inhibition) to 57 % (enhancement). The SA treatment stimulated PP in surface waters of coastal, estuarine, and shelf waters but suppressed it in the South China Sea basin. Such SA-induced changes in PP were significantly related to in situ pH and solar radiation in surface seawater but negatively related to salinity changes. Our results indicate that phytoplankton cells are more vulnerable to a pH drop in oligotrophic waters. Contrasting responses of phytoplankton productivity in different areas suggest that SA impacts on marine primary productivity are region-dependent and regulated by local environments.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2023-01-05.
DOI: 10.1594/pangaea.774581
title: Seawater carbonate chemistry and size of Strongylocentrotus purpuratus during experimetns, 2011

description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Lavigne and Gattuso, 2011) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI).
DOI: 10.1594/pangaea.916203
title: Seawater carbonate chemistry and fertilization rate of Mytilus galloprovincialis

description: Ocean acidification (OA) poses a major threat to marine organisms, particularly during reproduction when externally shed gametes are vulnerable to changes in seawater pH. Accordingly, several studies on OA have focused on how changes in seawater pH influence sperm behavior and/or rates of in vitro fertilization. By contrast, few studies have examined how pH influences prefertilization gamete interactions, which are crucial during natural spawning events in most externally fertilizing taxa. One mechanism of gamete interaction that forms an important component of fertilization in most taxa is communication between sperm and egg‐derived chemicals. These chemical signals, along with the physiological responses in sperm they elicit, are likely to be highly sensitive to changes in seawater chemistry. In this study, we experimentally tested this possibility using the blue mussel, Mytilus galloprovincialis, a species in which females have been shown to use egg‐derived chemicals to promote the success of sperm from genetically compatible males. We conducted trials in which sperm were allowed to swim in gradients of egg‐derived chemicals under different seawater CO2 (and therefore pH) treatments. We found that sperm had elevated fertilization rates after swimming in the presence of egg‐derived chemicals in low pH (pH 7.6) compared with ambient (pH 8.0) seawater. This observed effect could have important implications for the reproductive fitness of external fertilizers, where gamete compatibility plays a critical role in modulating reproduction in many species. For example, elevated sperm fertilization rates might disrupt the eggs' capacity to avoid fertilizations by genetically incompatible sperm. Our findings highlight the need to understand how OA affects the multiple stages of sperm‐egg interactions and to develop approaches that disentangle the implications of OA for female, male, and population fitness.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2020-05-6.
DOI: 10.1594/pangaea.846015
title: Biogeochemical and carbonate chemistry monthly variations in the Gulf of Trieste (C1 station) Italy

description: The data refers to 3 years of monthly measurements and sampling carried out in the frameworks of the FP7 MEDSEA (Mediterranean Sea Acidification in a Changing Climate) project at the C1 LTER station in the gulf of Trieste Italy (Northern Adriatic sea) from March 2011 to March 2014.
DOI: 10.1594/pangaea.856731
title: Calanus finmarchicus and Calanus glacialis incubated under elevated pCO2 during ARK-XXVII/1+2 and KOSMOS 2011 mesocosm experiments: environmental parameter