ALBERT

Description: n our daily lives, we consume foods that have been transported, stored, prepared, cooked, or otherwise processed by ourselves or others. Food storage and preparation have drastic effects on the chemical composition of foods. Untargeted mass spectrometry analysis of food samples has the potential to increase our chemical understanding of these processes by detecting a broad spectrum of chemicals. We performed a time-based analysis of the chemical changes in foods during common preparations, such as fermentation, brewing, and ripening, using untargeted mass spectrometry and molecular networking. The data analysis workflow presented implements an approach to study changes in food chemistry that can reveal global alterations in chemical profiles, identify changes in abundance, as well as identify specific chemicals and their transformation products. The data generated in this study are publicly available, enabling the replication and re-analysis of these data in isolation, and serve as a baseline dataset for future investigations.

Description: The 2010 Deepwater Horizon disaster remains the largest single accidental release of oil and gas into the ocean. During the 87-day release, scientists used oceanographic tools to collect wellhead oil and gas samples, interrogate microbial community shifts and activities, and track the chemical composition of dissolved oil in the ocean’s interior. In the decade since the disaster, field and laboratory investigations studied the physics and chemistry of irrupted oil and gas at high pressure and low temperature, the role of chemical dispersants in oil composition and microbial hydrocarbon degradation, and the impact of combined oil, gas and dispersants on the flora and fauna of coastal and deep-sea environments. The multi-faceted, multidisciplinary scientific response to the released oil, gas and dispersants culminated in a better understanding of the environmental factors that influence the short-term and long-term fate and transport of oil in marine settings. In this Review, we summarize the unique aspects of the Deepwater Horizon release and highlight the advances in oil chemistry and microbiology that resulted from novel applications of emerging technologies. We end with an outlook on the applicability of these findings to possible oil releases in future deep-sea drilling locations and newly-opened high-latitude shipping lanes.

Description: The concept of biosorption results from the “passive” (nonmetabolic) interaction of a chemical species with a particle of a biological material. This interaction can be practically exploited, for example, for removal of toxic substances of wastewaters or for the enrichment of a fertilizer with micronutrients. In this work, equilibrium and dynamic data obtained with “low-cost” biomaterials of algal waste or invasive seaweed species have been reviewed and critically analyzed in the context of a circular economy. The concept of a biosorption unit, oriented to the valorization of any solid residual material of algal biomass, can be considered as a real possibility in a biorefinery process; but to accomplish this goal it is necessary that the emphasis on research must definitely move from laboratory scale toward pilot plant assays.

Description: Natural cycles in the seawater partial pressure of carbon dioxide (CO2) in the Gulf of Maine, which vary in surface waters from ~250 to 550 µatm seasonally, provide an opportunity to observe how the life cycle and phenology of the shelled pteropod Limacina retroversa responds to changing food, temperature and carbonate chemistry conditions. Distributional, hydrographic, and physiological sampling suggest that pteropod populations are located in the upper portion of the water column (0–150 m) with a maximum abundance above 50 m. Gene expression and shell condition measurements show that the population already experiences biomineralization stress in the winter months when measured aragonite saturation state was at a seasonal low (though slightly oversaturated), reinforcing the usefulness of this organism as a bio-indicator for pelagic ecosystem response to ocean acidification. There appear to be two reproductive events per year with one pulse timed to coincide with the spring bloom, the period with highest respiration rate, fluorescence, and pH, and a second more extended pulse in the late summer and fall when saturation states remain high and fluorescence begins to decline. During the fall there is transcriptomic evidence of lipid storage for overwintering, allowing the second generation to survive the period of low food and aragonite saturation state. Based on these observations we predict that in the future pteropods will likely be most vulnerable to changing CO2 regionally during the fall reproductive event when CO2 concentration already naturally rises and when there is the added stress of generating lipid stores.

Description: The analysis of more than 400 papers found in the literature on Sargassum biosorption has shown the existence of more than 700 equilibrium entries corresponding to data at different temperature and pH conditions. The following ten single metals: Cd, Co, Cr(III, VI), Cu, Fe, Hg, La, Ni, Pb, and Zn, are the main focus of most of the equilibrium data (507) in more than half of the studied references. The studies reflecting the interaction of nine of these metals with Sargassum sp. is described and analyzed. The use of Langmuir equation, the effect of temperature and pH on sorption is critically reviewed. In addition, we also analyze all the data available on elemental chemical composition of native Sargassum. These data reflect the interaction of this kind of marine biomass with nine of the metals mentioned above, which are present in seawater worldwide.

Description: Despite their critical role as the main energy pathway between phytoplankton and fish, the functional complexity of zooplankton is typically poorly resolved in marine ecosystem models. Trait-based approaches—where zooplankton are represented with functional traits such as body size—could help improve the resolution of zooplankton in marine ecosystem models and their role in trophic transfer and carbon sequestration. Here, we present the Zooplankton Model of Size Spectra version 2 (ZooMSSv2), a functional size-spectrum model that resolves nine major zooplankton functional groups (heterotrophic flagellates, heterotrophic ciliates, larvaceans, omnivorous copepods, carnivorous copepods, chaetognaths, euphausiids, salps and jellyfish). Each group is represented by the functional traits of body size, size-based feeding characteristics and carbon content. The model is run globally at 5° resolution to steady-state using long-term average temperature and chlorophyll a for each grid-cell. Zooplankton community composition emerges based on the relative fitness of the different groups. Emergent steady-state patterns of global zooplankton abundance, biomass and growth rates agree well with empirical data, and the model is robust to changes in the boundary conditions of the zooplankton. We use the model to consider the role of the zooplankton groups in supporting higher trophic levels, by exploring the sensitivity of steady-state fish biomass to the removal of individual zooplankton groups across the global ocean. Our model shows zooplankton play a key role in supporting fish biomass in the global ocean. For example, the removal of euphausiids or omnivorous copepods caused fish biomass to decrease by up to 80%. By contrast, the removal of carnivorous copepods caused fish biomass to increase by up to 75%. Our results suggest that including zooplankton complexity in ecosystem models could be key to better understanding the distribution of fish biomass and trophic efficiency across the global ocean.

Description: Subsurface-intensified anticyclones are ubiquitous in the ocean, yet their impact on the large-scale transport of heat, salt and chemical tracers is poorly understood. These submesoscale coherent vortices (SCVs) can trap and advect waters thousands of kilometers away from the formation region, providing a transport pathway that is unresolved by low-resolution Earth System Models. However, knowledge of the importance of these eddies for the large scale circulation is hindered by the lack of systematic observations. Here, we take advantage of the global network of Argo floats to identify occurrences of these eddies, which appear as weakly stratified anomalous water masses with Gaussian-shaped vertical structures. We develop a general algorithm to detect subsurface eddies that have propagated away from their source region, and apply it to the database of Argo float profiles, resulting in roughly 4000 detections from more than 20 years of observations. We further group detections into regional populations to identify hot-spots of generation and mechanisms of formation. Analysis of regional SCV statistics reveals important sites of SCV generation in Eastern Boundary Upwelling Systems, marginal sea overflows, and mode water formation regions along major open-ocean fronts. Because of the heat and salt anomaly contained within their cores, SCV could leave a significant imprint on the hydrographic properties of water masses in regions of high SCV density.