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Subjective Well-being, Happiness, and Fairness of Marketing Systems in Brazil: Some Further Thoughts
Get PDFSubjective well-being is often popularly referred to as happiness. In this dialogue commentary, we point to these additional aspects of subjective well-being or happiness: (1) Some findings from another study of this type, in another region of Brazil; (2) Several macro-level observations, drawn from Brazil as well as globally, on the complex relationships between marketing practices, public policies, consumption styles and subjective well-being
Field validation of a novel passive sampler for dissolved PFAS in surface waters
Get PDFNumerous per- and polyfluoroalkyl substances (PFAS) are of growing concern worldwide due to their ubiquitous presence, bioaccumulation and adverse effects. Surface waters in the United States have displayed elevated concentrations of PFAS, but so far discrete water sampling has been the commonly applied sampling approach. In the present study we field-tested a novel integrative passive sampler, a microporous polyethylene tube, and derived sampling rates (Rs) for nine PFAS in surface waters. Three sampling campaigns were conducted, deploying polyethylene tube passive samplers in the effluent of two wastewater treatment plant (WWTP) effluents and across Narragansett Bay (Rhode Island, USA) for 1 month each in 2017 and 2018. Passive samplers exhibited linear uptake of PFAS in the WWTP effluents over 16–29 days, with in situ Rs for nine PFAS ranging from 10 ml day−1 (perfluoropentanoic acid) to 29 ml day−1 (perfluorooctanesulfonic acid). Similar sampling rates of 19 ± 4.8 ml day−1 were observed in estuarine field deployments. Applying these Rs values in a different WWTP effluent predicted dissolved PFAS concentrations mostly within 50% of their observations in daily composite water samples, except for perfluorobutanoic acid (where predictions from passive samplers were 3 times greater than measured values), perfluorononanoic acid (1.9 times), perfluorodecanoic acid (1.7 times), and perfluoropentanesulfonic acid (0.1 times). These results highlight the potential use of passive samplers as measurement and assessment tools of PFAS in dynamic aquatic environments
PAHs in the North Atlantic Ocean and the Arctic Ocean: Spatial Distribution and Water Mass Transport
Get PDFIn the Arctic Ocean, it is still unclear what role oceanic transport plays in the fate of semivolatile organic compounds. The strong-stratified Arctic Ocean undergoes complex inputs and outputs of polycyclic aromatic hydrocarbons (PAHs) from the neighboring oceans and continents. To better understand PAHs’ transport processes and their contribution to high-latitude oceans, surface seawater, and water column, samples were collected from the North Atlantic Ocean and the Arctic Ocean in 2012. The spatial distribution of dissolved PAHs (∑9PAH) in surface seawater showed an “Arctic Shelf \u3e Atlantic Ocean \u3e Arctic Basin” pattern, with a range of 0.3–10.2 ng L−1. Positive matrix factorization modeling results suggested that vehicle emissions and biomass combustion were the major PAHs sources in the surface seawater. According to principal component analysis, PAHs in different water masses showed unique profiles indicating their different origins. Carried by the Norwegian Atlantic Current (0–800 m) and East Greenland Current (0–300 m), PAH individuals’ net transport mass fluxes ranged from −4.4 ± 1.7 to 53 ± 39 tons year−1 to the Arctic Ocean. We suggested the limited contribution of ocean currents on PAHs’ delivery to the Arctic Ocean, but their role in modulating PAHs’ air–sea interactions and other biogeochemical processes needs further studies
Spatial origin analysis on atmospheric bulk deposition of polycyclic aromatic hydrocarbons in Shanghai
Get PDFAtmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) onto soil threatens terrestrial ecosystem. To locate potential source areas geographically, a total of 139 atmospheric bulk deposition samples were collected during 2012–2019 at eight sites in Shanghai and its surrounding areas. A multisite joint location method was developed for the first time to locate potential source areas of atmospheric PAHs based on an enhanced three dimensional concentration weighted trajectory model. The method considered spatial and temporal variations of atmospheric boundary layer height and homogenized all results over the eight sites via geometric mean. Regional transport was an important contributor of PAH atmospheric deposition while massive local emissions may disturb the identification of potential source areas. Northwesterly winds were associated with elevated deposition fluxes. Potential source areas were identified by the multisite joint location method and included Hebei, Tianjin, Shandong and Jiangsu to the north, and Anhui to the west of Shanghai. PM and SO2 data from the national ground monitoring stations confirmed the identified source areas of deposited PAHs in Shanghai
Crocosphaera as a Major Consumer of Fixed Nitrogen
Get PDFCrocosphaera watsonii (hereafter referred to as Crocosphaera) is a key nitrogen (N) fixer in the ocean, but its ability to consume combined-N sources is still unclear. Using in situ microcosm incubations with an ecological model, we show that Crocosphaera has high competitive capability both under low and moderately high combined-N concentrations. In field incubations, Crocosphaera accounted for the highest consumption of ammonium and nitrate, followed by picoeukaryotes. The model analysis shows that cells have a high ammonium uptake rate (;7 mol N [mol N]21 d21 at the maximum), which allows them to compete against picoeukaryotes and nondiazotrophic cyanobacteria when combined N is sufficiently available. Even when combined N is depleted, their capability of nitrogen fixation allows higher growth rates compared to potential competitors. These results suggest the high fitness of Crocosphaera in combined-N limiting, oligotrophic oceans heightening its potential significance in its ecosystem and in biogeochemical cycling
Erratum to “Quantifying Cyanothece growth under DIC limitation” [Comput. Struct. Biotechnol. J. 19 (2021) 6456–6464] (Computational and Structural Biotechnology Journal (2021) 19 (6456–6464), (S2001037021005018), (10.1016/j.csbj.2021.11.036))
No full textThe publisher regrets that the published version of some references contained errors that did not exist in the original manuscript. Correctly, references [26–28, 30, 40] should read as follows: [26] Inomura K, Bragg J, Riemann L, Follows MJ. A quantitative model of nitrogen fixation in the presence of ammonium. PLoS One 2018;13(11):e0208282. [27] Inomura K, Wilson ST, Deutsch C. Mechanistic model for the coexistence of nitrogen fixation and photosynthesis in marine Trichodesmium. mSystems 2019;4(4):e00210-19. [28] Inomura K, Follett CL, Masuda T, Eichner M, Prášil O, Deutsch C. Carbon transfer from the host diatom enables fast growth and high rate of N2 fixation by symbiotic heterocystous cyanobacteria. Plants 2020;9(2):192. [30] Inomura K, Deutsch C, Wilson ST, Masuda T, Lawrenz E, Bučinská L, et al. Quantifying oxygen management and temperature and light dependencies of nitrogen fixation by Crocosphaera watsonii. mSphere 2019;4(6):e00531-19. [40] Mulderij G, Mooij WM, Smolders AJP, Van Donk E. Allelopathic inhibition of phytoplankton by exudates from Stratiotes aloides. Aquat Bot 2005;82(4):284–96. The publisher would like to apologise for any inconvenience caused
Biological and geochemical proxies in sediment cores reveal shifts in marine predator population dynamics relative to historic anthropogenic exploitation and recent climate change at South Georgia Island sub-Antarctic
No full textHistorical climate change and human exploitation are thought to have played important roles in shaping population dynamics of sub-Antarctic marine predators, such as king penguins (Aptenodytes patagonicus) and Antarctic fur seals (Arctocephalus gazelle). For example, Antarctic fur seals on the sub-Antarctic South Georgia Island were nearly hunted to extinction by humans before the early 1900s. However, records of occupation history pre- and post-anthropogenic stress are often sporadic and challenging to interpret. In this study, we investigated paleoecological proxies in sediment cores from South Georgia Island to examine past marine predator population dynamics in the face of climate change and exploitation pressure. Sediment cores representing 1854 CE to present were collected from two sites on South Georgia Island in the South Atlantic and analyzed for geochemical (total carbon, total nitrogen, δ13C and δ15N values) and biological (e.g., seal hairs, penguin feathers) proxies. Proxies in both cores indicated the onset of the recovery of penguin and fur seal populations in the early to mid-1900s, following the cessation of hunting. Additionally, our results suggest marked increases in both penguin and seal populations beginning around 1950 CE. Between the 1950s and 2019, 97% of South Georgia Island’s glaciers retreated associated with recent climatic warming. This warming increased the availability of local breeding areas for king penguins, which likely explains the population rise during that time. This study deepens our understanding of the response of sub-Antarctic marine predator populations to past climate change and human exploitation, which may aid in predicting future ecosystem responses to environmental disturbance
Introduction to the Chemical Oceanography of Frontal Zones
No full textThis chapter provides a concise overview of the entire monograph by assembling summaries of 10 individual chapters starting with a global review of large-scale, persistent nutrient fronts of the World Ocean followed by regional chapters on the Arctic Ocean, North Atlantic, Baltic Sea, Kuroshio Current, and the Yellow Sea, a global review of CDOM dynamics at fronts, a chapter on persistent organic pollutants and marine organisms in the Kuroshio-Oyashio frontal zone, and two chapters on marine litter and its dynamics in frontal zones
The Deep Ocean Observing Strategy: Addressing Global Challenges in the Deep Sea Through Collaboration
No full textThe Deep Ocean Observing Strategy (DOOS) is an international, community-driven initiative that facilitates collaboration across disciplines and fields, elevates a diverse cohort of early career researchers into future leaders, and connects scientific advancements to societal needs. DOOS represents a global network of deep-ocean observing, mapping, and modeling experts, focusing community efforts in the support of strong science, policy, and planning for sustainable oceans. Its initiatives work to propose deep-sea Essential Ocean Variables; assess technology development; develop shared best practices, standards, and cross-calibration procedures; and transfer knowledge to policy makers and deep-ocean stakeholders. Several of these efforts align with the vision of the UN Ocean Decade to generate the science we need to create the deep ocean we want. DOOS works toward (1) a healthy and resilient deep ocean by informing science-based conservation actions, including optimizing data delivery, creating habitat and ecological maps of critical areas, and developing regional demonstration projects; (2) a predicted deep ocean by strengthening collaborations within the modeling community, determining needs for interdisciplinary modeling and observing system assessment in the deep ocean; (3) an accessible deep ocean by enhancing open access to innovative low-cost sensors and open-source plans, making deep-ocean data Findable, Accessible, Inter-operable, and Reusable, and focusing on capacity development in developing countries; and finally (4) an inspiring and engaging deep ocean by translating science to stakeholders/end users and informing policy and management decisions, including in international waters
Irminger Sea Is the Center of Action for Subpolar AMOC Variability
Get PDFSignificant societally important climate impacts can be caused by changes in the strength of the Atlantic Meridional Overturning Circulation (AMOC) at higher latitudes. Focusing on variability and long-term change of the subpolar North Atlantic (SPNA)—a key AMOC action center—and using eastern OSNAP array observations, we identify a distinct density and sea-surface height signature of the AMOC strength in the Irminger Sea (2014–2018), reinforced and extended with an ocean reanalysis (1993–2018). Reconstruction of AMOC variability using Irminger Sea density shows strong control by the North Atlantic Oscillation on subpolar overturning on multiple timescales, achieved via the gyre circulation and waters from the Labrador Sea. Furthermore, the observed decrease of Irminger Sea density since the mid-twentieth century (1950–2019) is suggestive of a long-term AMOC weakening of 2.2 Sv or 13%, however, this trend remains statistically insignificant due to the large interannual and decadal variability of the SPNA