cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.1594/pangaea.960151
title: Seawater carbonate chemistry and reallocation of elemental content and macromolecules in the coccolithophore Emiliania huxleyi

description: Global climate change leads to simultaneous changes in multiple environmental drivers in the marine realm. Although physiological characterization of coccolithophores has been studied under climate change, there is limited knowledge on the biochemical responses of this biogeochemically important phytoplankton group to changing multiple environmental drivers. Here, we investigate the interactive effects of reduced phosphorus availability (4 to 0.4 µmol L−1), elevated pCO2 concentrations (426 to 946 µatm), and increasing light intensity (40 to 300 µmol photons m−2 s−1) on elemental content and macromolecules of the cosmopolitan coccolithophore Emiliania huxleyi. Reduced phosphorus availability reduces particulate organic nitrogen (PON) and protein contents per cell under 40 µmol photons m−2 s−1 but not under 300 µmol photons m−2 s−1. Reduced phosphorus availability and elevated pCO2 concentrations act synergistically to increase particulate organic carbon (POC) and carbohydrate contents per cell under 300 µmol photons m−2 s−1 but not under 40 µmol photons m−2 s−1. Reduced phosphorus availability, elevated pCO2 concentrations, and increasing light intensity act synergistically to increase the allocation of POC to carbohydrates. Under elevated pCO2 concentrations and increasing light intensity, enhanced carbon fixation could increase carbon storage in the phosphorus-limited regions of the oceans where E. huxleyi dominates the phytoplankton assemblages. In each type of light intensity, elemental-carbon-to-phosphorus (C:P) and nitrogen-to-phosphorus (N:P) ratios decrease with increasing growth rate. These results suggest that coccolithophores could reallocate chemical elements and energy to synthesize macromolecules efficiently, which allows them to regulate their elemental content and growth rate to acclimate to changing environmental conditions.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2022) 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 2023-06-28.
DOI: 10.1594/pangaea.949280
title: Seawater carbonate chemistry and lipid content, particulate organic carbon/nitrogen, growth rate, and morphology of Emiliania huxleyi

description: Coccolithophores are a calcifying unicellular phytoplankton group that are at the base of the marine food web, and their lipid content provides a source of energy to consumers. Coccolithophores are vulnerable to ocean acidification and warming, therefore it is critical to establish the effects of climate change on these significant marine primary producers, and determine potential consequences that these changes can have on their consumers. Here, we quantified the impact of changes in pH and temperature on the nutritional condition (lipid content, particulate organic carbon/nitrogen), growth rate, and morphology of the most abundant living coccolithophore species, Emiliania huxleyi. We used a regression type approach with nine pH levels (ranging from 7.66 to 8.44) and two temperatures (15°C and 20°C). Lipid production was greater under reduced pH, and growth rates were distinctly lower at 15°C than at 20°C. The production potential of lipids, which estimates the availability of lipids to consumers, increased under 20°C, but decreased under low pH. The results indicate that, while consumers will benefit energetically under ocean warming, this benefit will be mitigated by ocean acidification. The carbon to nitrogen ratio was higher at 20°C and low pH, indicating that the nutritional quality of coccolithophores for consumers will decline under climate change. The impact of low pH on the structural integrity of the coccosphere may also mean that coccolithophores are easier to digest for consumers. Many responses suggest cellular stress, indicating that increases in temperature and reductions in pH may have a negative impact on the ecophysiology of coccolithophores.
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 2022-10-04.
DOI: 10.1594/pangaea.913498
title: Seawater carbonate chemistry and growth, production rates, and cellular composition of Arctic diatom

description: Arctic phytoplankton and their response to future conditions shape one of the most rapidly changing ecosystems on the planet. We tested how much the phenotypic responses of strains from the same Arctic diatom population diverge and whether the physiology and intraspecific composition of multistrain populations differs from expectations based on single strain traits. To this end, we conducted incubation experiments with the diatom Thalassiosira hyalina under present‐day and future temperature and pCO2 treatments. Six fresh isolates from the same Svalbard population were incubated as mono‐ and multistrain cultures. For the first time, we were able to closely follow intraspecific selection within an artificial population using microsatellites and allele‐specific quantitative PCR. Our results showed not only that there is substantial variation in how strains of the same species cope with the tested environments but also that changes in genotype composition, production rates, and cellular quotas in the multistrain cultures are not predictable from monoculture performance. Nevertheless, the physiological responses as well as strain composition of the artificial populations were highly reproducible within each environment. Interestingly, we only detected significant strain sorting in those populations exposed to the future treatment. This study illustrates that the genetic composition of populations can change on very short timescales through selection from the intraspecific standing stock, indicating the potential for rapid population level adaptation to climate change. We further show that individuals adjust their phenotype not only in response to their physicochemical but also to their biological surroundings. Such intraspecific interactions need to be understood in order to realistically predict ecosystem responses to global change.
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 2020-03-06.
DOI: 10.1594/pangaea.869470
title: Ocean warming modulates the effects of acidification on Emiliania huxleyi calcification and sinking

description: Ongoing ocean warming and acidification are tied to the rapid accumulation of human-induced carbon dioxide (CO2) in the atmosphere and subsequent uptake of heat and CO2 by the surface ocean. These processes are expected to drive large changes in marine ecosystems. While numerous studies have examined the effects of ocean acidification on coccolithophores, less is known on their combined effect. In this study, we investigate temperature modulation of the carbonate chemistry sensitivity of the coccolithophore Emiliania huxleyi (RCC1827 from the Western Mediterranean) in a culture experiment. We analyzed the responses of coccolith morphology, particulate inorganic and organic carbon production, and sinking rate of individual cells. E. huxleyi was exposed to three CO2 levels (ca. 400 µatm, 900 µatm, and 1400 µatm) at 15°C and 20°C. Temperature adds to the negative effect of increasing pCO2 on coccolith morphology, suggesting that a significant number of E. huxleyi strains might suffer from a temperature increase, hampering their evolutionary success. Temperature amplified the positive effect of increasing pCO2 on organic carbon production, while modulating the response of calcification rates, indicating that the response to increasing pCO2 must be taken with caution depending on the temperature range studied. Sinking rates were positively correlated with temperature, whereas pCO2 did not have any effect. The combined effect of carbonate chemistry and temperature on the E. huxleyi ratio between particulate inorganic carbon and particulate organic carbon (PIC/POC) might also lower the sinking rate of aggregates. In conclusion, in a warmer and more acidified ocean, individual coccolithophore cells might sink faster, while aggregates might sink slower.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2016) 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 is 2016-12-13.
description: Supplement to: Milner, Sara; Langer, Gerald; Grelaud, Michaël; Ziveri, Patrizia (2016): Ocean warming modulates the effects of acidification on Emiliania huxleyi calcification and sinking. Limnology and Oceanography, 61(4), 1322-1336
DOI: 10.1594/pangaea.904010
title: Acidification and irradiance effect on the photo-physiological fitness, growth and carbon production of the Antarctic cryptophyte Geminigera cryophila

description: Ecophysiological studies on Antarctic cryptophytes to assess whether climatic changes such as ocean acidification and enhanced stratification affect their growth in Antarctic coastal waters in the future are lacking so far. This is the first study that investigates the combined effects of the increasing availability of pCO2 (400 and 1000 μatm) and irradiance (20, 200 and 500 μmol photons m-2 s-1) on growth, elemental composition and photo-physiology of the Antarctic cryptophyte Geminigera cryophila. Under ambient pCO2, this species was characterized by a pronounced sensitivity to increasing irradiance with complete growth inhibition at the highest light intensity. Interestingly, when grown under high pCO2 this negative light effect vanished, and it reached the highest rates of growth and particulate organic carbon production at the highest irradiance compared to the other tested experimental conditions. Our results for G. cryophila reveal beneficial effects of ocean acidification in conjunction with enhanced irradiance on growth and photosynthesis. Hence, cryptophytes such as G. cryophila may be potential winners of climate change, potentially thriving better in more stratified and acidic coastal waters and contributing in higher abundance to future phytoplankton assemblages of coastal Antarctic waters.
description: #999: not grown
description: Supplement to: Trimborn, Scarlett; Thoms, Silke; Karitter, Pascal; Bischof, Kai (2019): Ocean acidification and high irradiance stimulate growth of the Antarctic cryptophyte Geminigera cryophila. Biogeosciences, 16, 2997–3008
DOI: 10.1594/pangaea.960341
title: Seawater carbonate chemistry and population-specific responses in physiological rates of Emiliania huxleyi to a broad CO2 range

description: Although coccolithophore physiological responses to CO2-induced changes in seawater carbonate chemistry have been widely studied in the past, there is limited knowledge on the variability of physiological responses between populations from different areas. In the present study, we investigated the specific responses of growth, particulate organic (POC) and inorganic carbon (PIC) production rates of three populations of the coccolithophore Emiliania huxleyi from three regions in the North Atlantic Ocean (Azores: six strains, Canary Islands: five strains, and Norwegian coast near Bergen: six strains) to a CO2 partial pressure (pCO2) range from 120 to 2630 µatm. Physiological rates of each population and individual strain increased with rising pCO2 levels, reached a maximum and declined thereafter. Optimal pCO2 for growth, POC production rates, and tolerance to low pH (i.e., high proton concentration) was significantly higher in an E. huxleyi population isolated from the Norwegian coast than in those isolated near the Azores and Canary Islands. This may be due to the large environmental variability including large pCO2 and pH fluctuations in coastal waters off Bergen compared to the rather stable oceanic conditions at the other two sites. Maximum growth and POC production rates of the Azores and Bergen populations were similar and significantly higher than that of the Canary Islands population. This pattern could be driven by temperature–CO2 interactions where the chosen incubation temperature (16 °C) was slightly below what strains isolated near the Canary Islands normally experience. Our results indicate adaptation of E. huxleyi to their local environmental conditions and the existence of distinct E. huxleyi populations. Within each population, different growth, POC, and PIC production rates at different pCO2 levels indicated strain-specific phenotypic plasticity. Accounting for this variability is important to understand how or whether E. huxleyi might adapt to rising CO2 levels.
description: In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2022) 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 2023-07-05.
DOI: 10.1594/pangaea.922459
title: Seawater carbonate chemistry and growth and particulate organic nitrogen production of diatom Thalassiosira pseudonana

description: Phytoplankton in the upper oceans are exposed to changing light levels due to mixing, diurnal solar cycles and weather conditions. Consequently, effects of ocean acidification are superimposed upon responses to variable light levels. We therefore grew a model diatom Thalassiosira pseudonana under either constant or variable light but at the same daily photon dose, with current low (400 μatm, LC) and future high CO2 (1000 μatm, HC) treatments. Variable light, compared with the constant light regime, decreased the growth rate, Chl a, Chl c, and carotenoid contents under both LC and HC conditions. Cells grown under variable light appeared more tolerant of high light as indicated by higher maximum relative electron transport rate and saturation light. Light variation interacted with high CO2/lowered pH to decrease the carbon fixation rate, but increased particulate organic carbon (POC) and particularly nitrogen (PON) per cell, which drove a decrease in C/N ratio, reflecting changes in the efficiency of energy transfer from photo-chemistry to net biomass production. Our results imply that elevated pCO2 under varying light conditions can lead to less primary productivity but more PON per biomass of the diatom, which might improve the food quality of diatoms and thereby influence biogeochemical nitrogen cycles.
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 2020-07-07.
DOI: 10.15468/dl.87qw9d
title: Occurrence Download

description: A dataset containing 0 species occurrences available in GBIF matching the query:
{
 "and" : [
 "TaxonKey is Argyreia nervosa",
 "Country is Cook Islands",
 "HasCoordinate is true"
 ]
}

 The dataset includes 0 records from 0 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0051770-250827131500795/datasets/export for details.
DOI: 10.15468/dl.ufrp73
title: Occurrence Download

description: A dataset containing 1421 species occurrences available in GBIF matching the query:
{
 "TaxonKey" : [
 "is Prunus maackii"
 ]
}

 The dataset includes 1421 records from 93 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0051769-250827131500795/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.1594/pangaea.907767
title: Seawater carbonate chemistry and productivity and species composition of a late summer phytoplankton community of the coastal Western Antarctic Peninsula

description: The Western Antarctic Peninsula (WAP), one of the most productive regions of the Southern Ocean, is currently undergoing rapid environmental changes such as ocean acidification (OA) and increased daily irradiances from enhanced surface‐water stratification. To assess the potential for future biological CO2 sequestration of this region, we incubated a natural phytoplankton assemblage from Ryder Bay, WAP, under a range of pCO2 levels (180 μatm, 450 μatm, and 1000 μatm) combined with either moderate or high natural solar radiation (MSR: 124 μmol photons/m**2/s and HSR: 435 μmol photons/ m**2/s, respectively). The initial and final phytoplankton communities were numerically dominated by the prymnesiophyte Phaeocystis antarctica, with the single cells initially being predominant and solitary and colonial cells reaching similar high abundances by the end. Only when communities were grown under ambient pCO2 in conjunction with HSR did the small diatom Fragilariopsis pseudonana outcompete P. antarctica at the end of the experiment. Such positive light‐dependent growth response of the diatom was, however, dampened by OA. These changes in community composition were caused by an enhanced photosensitivity of diatoms, especially F. pseudonana, under OA and HSR, reducing thereby their competitiveness toward P. antarctica. Moreover, community primary production (PP) of all treatments yielded similar high rates at the start and the end of the experiment, but with the main contributors shifting from initially large to small cells toward the end. Even though community PP of Ryder Bay phytoplankton was insensitive to the changes in light and CO2 availability, the observed size‐dependent shift in productivity could, however, weaken the biological CO2 sequestration potential of this region in the future.
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 2019-10-24.
description: Supplement to: Heiden, Jasmin; Völkner, Christian; Jones, Elizabeth M; van De Poll, Willem H; Buma, Anita G J; Meredith, Michael P; de Baar, Hein J W; Bischof, Kai; Wolf-Gladrow, Dieter A; Trimborn, Scarlett (2019): Impact of ocean acidification and high solar radiation on productivity and species composition of a late summer phytoplankton community of the coastal Western Antarctic Peninsula. Limnology and Oceanography, 64(4), 1716-1736
DOI: 10.1594/pangaea.964944
title: Seawater carbonate chemistry and Isochrysis sp.'s responses to temperature (2 vs. 6 °C), light (55 vs. 160 µmol photons m-2 s-1) and pCO2 (400 vs. 1000 µatm)

description: We assessed the responses of solitary cells of Arctic Isochrysis sp. grown under a matrix of temperature (2°C vs. 6°C), light intensity (55 vs. 160 μmol photons m-2 s-1) and CO2 partial pressures (pCO2; 400 vs. 1000 μatm). Before the experiments, the strain (isolated during Polarstern cruise PS78 in 2011) was kept as stock culture at 1° in 0.2 µm sterile-filtered Arctic seawater (Salinity 33), enriched with vitamins and trace metals according to F/2 medium (Guillard & Ryther, 1962). Nitrate and phosphate were added in concentrations of 100 and 6 µmol L-1, respectively. Experiments were conducted between May 2016 and September 2017 at the Alfred-Wegener-Institute, using standardized media and continuous light exposition. Next to acclimation parameters (growth rates, particulate and dissolved organic carbon and nitrogen, chlorophyll a content), we measured physiological processes in-vivo (electron transport rates and net photosynthesis) using fast-repetition rate fluorometry and membrane-inlet mass spectrometry. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2022) 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 2024-01-20.
DOI: 10.1594/pangaea.860225
title: Response of a natural phytoplankton community from the Qingdao coast (Yellow Sea, China) to variable CO2 levels over a short-term incubation experiment

description: Since marine phytoplankton play a vital role in stabilizing earth's climate by removing significant amount of atmospheric CO2, their responses to increasing CO2 levels are indeed vital to address. The responses of a natural phytoplankton community from the Qingdao coast (NW Yellow Sea, China) was studied under different CO2 levels in microcosms. HPLC pigment analysis revealed the presence of diatoms as a dominant microalgal group; however, members of chlorophytes, prasinophytes, cryptophytes and cyanophytes were also present. delta 13CPOM values indicated that the phytoplankton community probably utilized bicarbonate ions as dissolved inorganic carbon source through a carbon concentration mechanism (CCM) under low CO2 levels, and diffusive CO2 uptake increased upon the increase of external CO2 levels. Although, considerable increase in phytoplankton biomass was noticed in all CO2 treatments, CO2-induced effects were absent. Higher net nitrogen uptake under low CO2 levels could be related to the synthesis of CCM components. Flow cytometry analysis showed slight reduction in the abundance of Synechococcus and pico-eukaryotes under the high CO2 treatments. Diatoms did not show any negative impact in response to increasing CO2 levels; however, chlorophytes revealed a reverse tend. Heterotrophic bacterial count enhanced with increasing CO2 levels and indicated higher abundance of labile organic carbon. Thus, the present study indicates that any change in dissolved CO2 concentrations in this area may affect phytoplankton physiology and community structure and needs further long-term study.
description: The value of biological parameters under 3 pCO2 levels are the final day value. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2015) 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 is 2016-05-13.
description: Supplement to: Biswas, Haimanti; Jie, Jin; Li, Ying; Zhang, Guosen; Zhu, Zhuoyi; Wu, Ying; Zhang, Guoling; Li, Yanwei; Liu, Sumei; Zhang, Jing (2015): Response of a natural phytoplankton community from the Qingdao coast (Yellow Sea, China) to variable CO2 levels over a short-term incubation experiment. Current Science, 108(10), 1901-1909