Phytoplankton areas throughout non permanent wetlands underneath different climate scenarios

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g., •NO2 and •NO) formed from the decomposition of FNA. We further revealed that it was HNO2 that caused the breakdown, rather than the exclusive action of the acid (H+) or nitrite (NO2-) counterparts. The fragmentation of these representative cell envelope molecules provides insight into the biocidal effects of FNA on microorganisms.Health concerns and related regulation of bisphenol A (BPA) in some countries have led to an increase in the production and use of unregulated and poorly understood BPA analogues, including bisphenol S (BPS), bisphenol F (BPF), bisphenol B (BPB), and bisphenol AF (BPAF). AZD-9574 To assess the temporal trends of human exposure to BPA analogues, urine and wastewater samples were collected from South East Queensland, Australia between 2012 and 2017 and analyzed for five bisphenols using validated isotope dilution liquid chromatography tandem mass spectrometry methods. BPA and BPS were the predominant bisphenols detected in both urine and wastewater samples, with median concentrations of 2.5 and 0.64 μg/L in urine and 0.94 and 1.1 μg/L in wastewater, respectively. BPB, BPF, and BPAF had low detection frequencies in both urine and wastewater samples. Concentrations of BPA in both urine and wastewater decreased over the sampling period, whereas concentrations of BPS increased, suggesting that BPS has become a BPA replacement. The contributions of urinary excretion to wastewater were calculated by the ratio of daily per capita urinary excretion to wastewater-based mass loads of bisphenols. Urinary BPA and BPS contributed to less than 1% of the load found in wastewater, indicating that much of the BPA and BPS originates from other sources.The surface mining and bitumen extraction of oil sands (OS) generates over one million barrels of heavy oil each day in the Alberta Oil Sands Region of Canada. Recent observations suggest that emissions from OS development contribute to secondary organic aerosol (SOA) formation, but the chemical composition, mass fluxes, and sources of those emissions are poorly delineated. Here, we simulated OS extraction and used comprehensive two-dimensional gas chromatography to quantify and characterize direct air emissions, bitumen froth, residual wastewater, and tailings components, ultimately enabling fate modeling of over 1500 chromatographic features simultaneously. During the non-ice cover season, tailings ponds emissions contributed 15 000-72 000 metric tonnes of hydrocarbon SOA precursors, translating to 3000-13 000 tonnes of SOA, whereas direct emissions during the extraction process itself were notably smaller (960 ± 500 tonnes SOA yr-1). These results suggest that tailings pond waste management practices should be targeted to reduce environmental emissions.Transition-metal-activated sulfite [S(IV)] processes for water decontamination have recently received intense attention in the field of decontamination by advanced oxidation processes (AOPs). However, the drawback with respect to the secondary metal sludge contamination involved in various AOPs has been argued often. In this work, we developed a novel electro-sulfite (ES) process using stable and low-cost graphite electrodes to address that concern. Arsenite [As(III)] was used as the target compound for removal by the ES process because of its wide presence and high toxicity. Parameters, including cell voltage, S(IV) concentration, solution pH, and water matrix, and the mechanisms for reactions on anode and cathode were investigated in electrolytic cells containing one or two compartments, respectively. The results show that the ES process using 1 mM S(IV) and 2 V cell voltage oxidizes 5 μM As(III) at a rate of 0.127 min-1, which is 15-fold higher than mere electrolysis without S(IV) addition (0.008 min-1) at pH 7. Further studies using radical scavengers and electron spin resonance assays demonstrated that oxysulfur radicals (i.e., SO5•- and SO4•-) and HO• are responsible for As(III) oxidation in the ES process. However, HO2• produced via the oxygen reduction reaction in the EO process plays a major role in As(III) oxidation, which explains the lower reaction rate in the absence of S(IV). The effectiveness of the ES process was moreover evidenced by 60-82% As(III) oxidation in field water within 40 min. Overall, this work realizes the metal-free activation of S(IV) and significantly leverages the S(IV)-based water treatment technologies.Animals incorporate metals within the materials they manufacture, such as protective armor and teeth. Iron is an element used for adding strength and self-healing properties to load-bearing materials. Incorporation of iron is found beyond hard, brittle materials, even within the soft adhesive produced by marine mussels. Such findings suggest that the bioavailability of iron may have an influence on the properties of a biological material. Experiments were conducted using live mussels in which seawater iron levels were deficient, normal, or in excess of typical concentrations. The weakest adhesive strengths were produced in iron-deficient waters. Increasing seawater iron brought about more robust bonding. Changes in strengths correlated with varied adhesive morphology, color, and microstructural features, likely a result of variations in the degree of iron-induced protein cross-linking. This study provides the first whole animal scale data on how the manipulation of bioavailable iron influences the performance of a biological material. Changing ocean chemistries will alter the iron bioavailability when a decrease in pH shifts elemental speciation from particulate to dissolved, hindering the ability of filtering organisms to capture nutrients. These results show future implications of changing ocean chemistry as well as of the resulting abilities of marine organisms to construct essential materials.Houston, Texas is a major U.S. urban and industrial area where poor air quality is unevenly distributed and a disproportionate share is located in low-income, non-white, and Hispanic neighborhoods. We have traditionally lacked city-wide observations to fully describe these spatial heterogeneities in Houston and in cities globally, especially for reactive gases like nitrogen dioxide (NO2). Here, we analyze novel high-spatial-resolution (250 m × 500 m) NO2 vertical columns measured by the NASA GCAS airborne spectrometer as part of the September-2013 NASA DISCOVER-AQ mission and discuss differences in population-weighted NO2 at the census-tract level. Based on the average of 35 repeated flight circuits, we find 37 ± 6% higher NO2 for non-whites and Hispanics living in low-income tracts (LIN) compared to whites living in high-income tracts (HIW) and report NO2 disparities separately by race ethnicity (11-32%) and poverty status (15-28%). We observe substantial time-of-day and day-to-day variability in LIN-HIW NO2 differences (and in other metrics) driven by the greater prevalence of NO x (≡NO + NO2) emission sources in low-income, non-white, and Hispanic neighborhoods.