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We present optically-derived estimates of phytoplankton carbon (Cphyto) and chlorophyll a concentration (Chl) across a wide range of productivity and hydrographic regimes in the Subarctic Pacific Ocean. Our high-frequency measurements capture changes in Cphyto and Chl across regional gradients in macro- and micronutrient limitation, and sub-mesoscale hydrographic frontal zones. Throughout the majority of our survey region, carbon to chlorophyll ratios (Cphyto:Chl) ranged between 50-100. Lower values (10-20) were constrained to the highly productive coastal upwelling system along Vancouver Island, whereas higher estimated values (>200) were found directly off the southern British Columbia continental shelf. Further offshore, Cphyto:Chl was less variable, ranging from 50-80 in high nutrient low Chl (HNLC) waters in June, and from 80-120 in the Gulf of Alaska in July. Much of the variability in Cphyto:Chl throughout the study region could be explained by mixed layer light levels (i.e. photo-acclimation), with additional variability attributed to nutrient-controlled changes in phytoplankton growth rates in some regions. Elevated Cphyto:Chl ratios resulting from apparent nutrient stress were found in areas of low macro-nutrient concentrations. In contrast, iron-limited waters exhibited Cphyto:Chl ratios lower than predicted from the photo-acclimation model. Applying the Carbon-based production model, we derived Cphyto and Chl-based estimates of net primary productivity, which showed good coherence with independent 14C uptake measurements. Our results highlight the utility of ship-board optical data to examine phytoplankton physiological ecology and productivity in surface marine waters. Supplement to: Burt, William J; Westberry, Toby K; Behrenfeld, Michael J; Zeng, Chen; Izett, Robert W; Tortell, Philippe Daniel (2018): Carbon : Chlorophyll ratios and net primary productivity of Subarctic Pacific surface waters derived from autonomous shipboard sensors. Global Biogeochemical Cycles

The Chinese Loess Plateau red clay sequences display a continuous alternation of sedimentary cycles that represent recurrent climatic fluctuations from 2.58 Ma to the Miocene. Deciphering such a record can provide us with vital information on global and Asian climatic variations. Lack of fossils and failure of absolute dating methods made magnetostratigraphy a leading method to build age models for the red clay sequences. Here we test the magnetostratigraphic age model against cyclostratigraphy. For this purpose we investigate the climate cyclicity recorded in magnetic susceptibility and sedimentary grain size in a red clay section previously dated 11Myr old with magnetostratigraphy alone. Magnetostratigraphy dating based on only visual correlation could potentially lead to erroneous age model. In this study the correlation is executed through the iteration procedure until it is supported by cyclostratigraphy; i.e., Milankovitch cycles are resolved in the best possible manner. Our new age model provides an age of 5.2Ma for the Shilou profile. Based on the new age model, wavelet analysis reveals the well-preserved 400 kyr and possible 100 kyr eccentricity cycles on the eastern Chinese Loess Plateau. Further, paleomonsoonevolution during 2.58-5.2Ma is reconstructed and divided into three intervals (2.58-3.6Ma, 3.6-4.5Ma, and 4.5-5.2Ma). The upper part, the youngest stage, is characterized by a relatively intensified summer monsoon, the middle stage reflects an intensification of the winter monsoon and aridification in Asia, and the earliest stage indicates that summer and winter monsoon cycles may have rapidly altered. The use of cyclostratigraphy along withmagnetostratigraphy gives us an effectivemethod of dating red clay sequences, and our results imply that many presently published age models for the red clay deposits should be perhaps re-evaluated. Supplement to: Anwar, Taslima; Kravchinsky, Vadim; Zhang, Rui (2015): Magneto- and cyclostratigraphy in the red clay sequence: New age model and paleoclimatic implication for the eastern Chinese Loess Plateau. Journal of Geophysical Research: Solid Earth, 120(10), 6758–6770

1. Ballast water has been identified as a leading vector for introduction of non-indigenous species (NIS). Recently, the International Maritime Organization (IMO) implemented management standards – D-2 – where all large, commercial ships trading internationally are required to adopt an approved treatment system using technologies such as ultraviolet radiation or chlorination. However, current management regulations are based only on the total abundance of viable taxa transported (i.e., total propagule pressure), largely ignoring species richness (i.e., colonization pressure).2. To determine the efficacy of chlorine treatment in reducing invasion risks and changes in transported biological communities inside ballast tanks, we used DNA metabarcoding-based approaches to estimate colonization pressure (here, the number of species/Operational Taxonomic Units (OTUs) introduced) and relative propagule pressure (relative abundance of each species/OTU) of zooplankton communities in control and chlorine treated tanks during four transatlantic voyages. 3. Our study demonstrated that transport itself did not significantly reduce colonization pressure of zooplankton species, nor did chlorine treatment. Chlorine treatment altered community structure by reducing relative propagule pressure of some taxa such as Mollusca and Rotifera, while increasing relative propagule pressure of some Oligohymenophorea and Copepoda species.4. Synthesis and applications. Chlorine treatment may not reduce invasion risks as much as previously thought. Reduction in total propagule pressure does not mean reduction in abundance of all species equally. While some taxa might experience drastically reduced abundance, others might not change at all or increase due to hatching from dormant stages initiated by chlorine exposure. Therefore, management strategies should consider changes in total propagule pressure and colonization pressure when forecasting risk of new invasions. We therefore recommend adopting new approaches, such as DNA metabarcoding-based methods, to assess the whole biodiversity discharged from ballast water. As species responses to chlorine treatment are variable and affected by concentration, we also recommend a combination of different technologies to reduce introduction risks of aquatic organisms. Supplement to: Lin, Yaping; Zhan, Aibin; Hernandez, Marco R; Paolucci, Esteban; MacIsaac, Hugh J; Briski, Elizabeta (2020): Can chlorination of ballast water reduce biological invasions? Journal of Applied Ecology, 57(2), 331-343 The zip file includes:1. raw_data_clean.fasta: Raw sequence reads of zooplankton in ballast water samples2. raw_data.fasta: OTU representative sequences3. OTU_table.xlsx: OTU table

Supplement to: Callbeck, Cameron; Lavik, Gaute; Ferdelman, Timothy G; Fuchs, Bernhard M; Gruber-Vodicka, Harald R; Hach, Philipp F; Littmann, Sten; Schoffelen, Niels J; Kalvelage, Tim; Thomsen, Soeren; Schunck, Harald; Löscher, Carolin R; Schmitz, Ruth A; Kuypers, Marcel MM (2018): Oxygen minimum zone cryptic sulfur cycling sustained by offshore transport of key sulfur oxidizing bacteria. The data set includes, sulfide and sulfur concentrations, SUP05 cell densities, as well as denitrification and carbon fixation rates (based on 15N- and 13C-labelled in situ incubation experiments). The transect extends from the sulfidic upper shelf into the sulfide-free offshore oxygen minimum zone.

The Athabasca Basin (Canada) contains the highest grade unconformity-type uranium deposits in the world. Underlying the Athabasca Group sedimentary rocks of the Dufferin Lake zone are variably graphitic pelitic schists (VGPS), altered to chlorite and hematite (Red/Green Zone: RGZ), and locally bleached near the unconformity during paleoweathering and/or later fluid interaction, leading to a loss of graphite near the unconformity. Fluid inclusions were examined in different generations of quartz veins, using microthermometry and Raman analysis, to characterize and compare the different fluids that interacted with the RGZ and the VGPS. In the VGPS, CH4-, N2- and CO2-rich fluids circulated. CH4- and N2-rich fluids could be the result of the breakdown of graphite to CH4/CO2, whereas N2-rich fluid is interpreted to be the result of breakdown of feldspars/micas to NH4+/N2. In the RGZ, highly saline fluids interpreted to be basinally derived have been recorded. The circulation of the two types of fluids (carbonic and brines) occurred at two different distinct events: 1) during the retrograde metamorphism of the basement rocks before the deposition of the Athabasca Basin for the carbonic fluids, and 2) after the deposition of the Athabasca Basin for the brines. Thus, in addition to possibly be related to graphite depletion in the RGZ, the brines can be linked to uranium mineralization. Supplement to: Pascal, Marjolaine; Boiron, Marie-Christine; Ansdell, Kevin; Annesley, Irvine R; Kotzer, Tom; Jiricka, Dan; Cuney, Michel (2016): Fluids preserved in variably altered graphitic pelitic schists in the Dufferin Lake zone, south-central Athabasca Basin, Canada: Implications for graphite loss and uranium deposition. Mineralium Deposita, 51(5), 619-636

Data collected in July, 2016 aboard the R/V Oceanus using an underway flow-through system. For detailed information regarding this system, refer to Burt et al. (2018) and Burt and Tortell (2018). Particulate backscatter (bbp) is presented in two formats. 'Binned' data refers to measurements that have undergone regular processing techniques, namely minute-binning and median filtering. Important metadata, including ships position, salinity, and chlorophyll, are all minute-binned. 'Raw' bbp data refers to measurements not binned or median-filtered, which are higher-resolution (1 Hz, or per-second), and include a number of large 'spikes'. The height of each individual spike ('spikeheight') is also given. For more information regarding the specifics of this data, please refer to Burt and Tortell (2018).Note: The raw data consists of over 1 million time points, and thus has been split into two separate files. Supplement to: Burt, William J; Tortell, Philippe Daniel (2018): Observations of zooplankton diel vertical migration from high-resolution surface ocean optical measurements. Geophysical Research Letters, 45

Ocean warming and acidification are concomitant global drivers that are currently threatening the survival of marine organisms. How species will respond to these changes depends on their capacity for plastic and adaptive responses. Little is known about the mechanisms that govern plasticity and adaptability or how global changes will influence these relationships across multiple generations. Here, we exposed the emerging model marine polychaete Ophryotrocha labronica to conditions simulating ocean warming and acidification, in isolation and in combination over five generations to identify: (i) how multiple versus single global change drivers alter both juvenile and adult life-traits; (ii) the mechanistic link between adult physiological and fitness-related life-history traits; (iii) whether observed phenotypic changes observed over multiple generations are of plastic and/or adaptive origin. Two juvenile (developmental rate; survival to sexual maturity) and two adult (average reproductive body size; fecundity) life-history traits were measured in each generation, in addition to three physiological (cellular reactive oxygen species content, mitochondrial density; mitochondrial capacity) traits. We found that multi-generational exposure to warming alone caused an increase in: juvenile developmental rate, reactive oxygen species production and mitochondrial density and decreases in: average reproductive body size, fecundity and fluctuations in mitochondrial capacity, relative to control conditions. While exposure to ocean acidification alone, had only minor effects on juvenile developmental rate. Remarkably, when both drivers of global change were present, only mitochondrial capacity was significantly affected, suggesting that ocean warming and acidification act as opposing vectors of stress across multiple generations. 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 2016-11-29. Supplement to: Gibbin, Emma M; Chakravarti, Leela Jackie; Jarrold, Michael; Christen, Felix; Turpin, Vincent; Massamba-N'siala, Gloria; Blier, Pierre; Calosi, Piero (2017): Can multi-generational exposure to ocean warming and acidification lead to the adaptation of life history and physiology in a marine metazoan? Journal of Experimental Biology, 220(4), 551-563

High-grade gold and uranium mineralization in the Witwatersrand basin is intimately associated with pyrobitumen, implying that hydrocarbons may have played a role in the genesis of these ores. The nature of the pyrobitumen in the Carbon Leader Reef was therefore investigated to determine if hydrocarbons were essential to the ore-forming process. The relative proportions of trace elements in pyrobitumen seams and nodules are, in large part, similar to those of organic-rich shales located within the sedimentary succession. This indicates a strong genetic relationship between the pyrobitumen and the shales. A network of veins and veinlets filled with pyrobitumen, and the occurrence of oil inclusions in detrital and authigenic quartz grains, provide compelling evidence that the pyrobitumen was derived from a mobile (liquid hydrocarbon) precursor that circulated in the Carbon Leader Reef. Uranium, Au, Sb, Pb, Ag, Te, Th, Bi, Se and W are enriched relative to their concentrations in the shales. This is particularly the case for U and Au. The pervasive and relatively homogeneous distribution of the uranium is consistent with the presence of ubiquitous, submicroscopic uraninite in the pyrobitumen documented in an earlier study. In contrast, the distribution of the gold is heterogeneous, indicating the presence of irregularly distributed gold micrograins. These grains are concentrated mainly in the interstices between pyrobitumen nodules. Secondary minerals, such as brannerite, monazite-(Ce) and galena, are also concentrated in these interstices.On the basis of this study, we propose that intrabasinal shale units of the Witwatersrand Supergroup were the source for the pyrobitumen in the Carbon Leader Reef. These shales produced and released liquid hydrocarbons during the burial of the sedimentary succession. Phyllosilicates enriched in trace metals were transferred from the shales into the newly produced liquid hydrocarbons and were transported stratigraphically upward by the latter into the Carbon Leader Reef. During migration, the liquid hydrocarbons dissolved detrital uraninite present in the basin, adding to the uranium budget. The liquid hydrocarbons were converted into pyrobitumen in response to further burial, and precipitated uraninite nanocrystals. Post-depositional, hydrothermal fluids interacted with the hydrocarbons and deposited gold by reduction on hydrocarbon surfaces. The interaction of these fluids with the hydrocarbons may have released U, Th, REE, Pb and Ti from the hydrocarbons and triggered the formation of secondary brannerite, monazite-(Ce) and galena. The results of this study provide convincing evidence that the hydrocarbon liquids that formed the pyrobitumen seams in the Carbon Leader Reef played an essential role in the remobilization and redeposition of uranium and gold, respectively, in the Witwatersrand Supergroup. Supplement to: Fuchs, Sebastian; Williams-Jones, Anthony E; Jackson, Simon E; Przybylowicz, Wojciech J (2016): Metal distribution in pyrobitumen of the Carbon Leader Reef, Witwatersrand Supergroup, South Africa: Evidence for liquid hydrocarbon ore fluids. Chemical Geology, 426, 45-59

In order to understand how ocean acidification (OA) and enhanced irradiance levels might alter phytoplankton eco-physiology, productivity and species composition, we conducted an incubation experiment with a natural plankton assemblage from sub-surface Subarctic waters (Davis Strait, 63°N). The phytoplankton assemblage was exposed to 380 and 1,000 µatm pCO2 at both 15 and 35% surface irradiance over 2 weeks. The incubations were monitored and characterized in terms of their photo-physiology, biomass stoichiometry, primary production and dominant phytoplankton species. We found that the phytoplankton assemblage exhibited pronounced high-light stress in the first days of the experiment (20-30% reduction in photosynthetic efficiency, Fv/Fm). This stress signal was more pronounced when grown under OA and high light, indicating interactive effects of these environmental variables. Primary production in the high light treatments was reduced by 20% under OA compared to ambient pCO2 levels. Over the course of the experiment, the assemblage fully acclimated to the applied treatments, achieving similar bulk characteristics (e.g., net primary production and elemental stoichiometry) under all conditions. We did, however, observe a pCO2-dependent shift in the dominant diatom species, with Pseudonitzschia sp. dominating under low and Fragilariopsis sp. under high pCO2 levels. Our results indicate an unexpectedly high level of resilience of Subarctic phytoplankton to OA and enhanced irradiance levels. The co-occurring shift in dominant species suggests functional redundancy to be an important, but so-far largely overlooked mechanism for resilience toward climate change. Supplement to: Hoppe, Clara Jule Marie; Schuback, Nina; Semeniuk, David M; Maldonado, Maria T; Rost, Björn (2017): Functional Redundancy Facilitates Resilience of Subarctic Phytoplankton Assemblages toward Ocean Acidification and High Irradiance. Frontiers in Marine Science, 4, 14 pp