Increasing energy consumption and food production worldwide results in anthropogenic emissions of reactive nitrogen into the atmosphere. To date, however, little information is available on tropical urban environments where inorganic nitrogen is vastly transported and deposited through precipitation on terrestrial and aquatic ecosystems. To fill this gap, we present compositions of water stable isotopes in precipitation and atmospheric nitrate (δO-HO, δH-HO, δN-NO, and δO-NO) collected daily between August 2018 and November 2019 in a tropical urban atmosphere of central Costa Rica. Rainfall generation processes (convective and stratiform rainfall fractions) were identified using stable isotopes in precipitation coupled with air mass back trajectory analysis. A Bayesian isotope mixing model using δN-NO compositions and corrected for potential N fractionation effects revealed the contribution of lightning (25.9 ± 7.1%), biomass burning (21.8 ± 6.6%), gasoline (19.1 ± 6.4%), diesel (18.4 ± 6.0%), and soil biogenic emissions (15.0 ± 2.6%) to nitrate wet deposition. δO-NO values reflect the oxidation of NO sources via the ·OH + RO pathways. These findings provide necessary baseline information about the combination of water and nitrogen stable isotopes with atmospheric chemistry and hydrometeorological techniques to better understand wet deposition processes and to characterize the origin and magnitude of inorganic nitrogen loadings in tropical regions.
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http://dx.doi.org/10.1007/s11356-021-15327-x | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Earth Sciences, University of Oregon, Eugene, OR 97403.
Volcanic provinces are among the most active but least well understood landscapes on Earth. Here, we show that the central Cascade arc, USA, exhibits systematic spatial covariation of topography and hydrology that are linked to aging volcanic bedrock, suggesting systematic controls on landscape evolution. At the Cascade crest, a locus of Quaternary volcanism, water circulates deeply through the upper [Formula: see text]1 km of crust but transitions to shallow and dominantly horizontal flow as rocks age away from the arc front.
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January 2025
Environmental Chemistry Laboratory, Institute of Chemistry, University of Campinas, Campinas, São Paulo 13083970, Brazil. Electronic address:
Brazil's extensive agricultural area makes it the world's leading soybeans and sugarcane producer. Therefore, the use of large amounts of pesticides directly impacts all environmental compartments, including rainwater. We analyzed 14 pesticides and 5 degradation products in rainwater from three cities in the State of São Paulo, southeastern Brazil, with distinct land uses.
View Article and Find Full Text PDFTissue Cell
January 2025
Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Mechanical loading plays a pivotal role in regulating bone anabolic processes. Understanding the optimal mechanical loading parameters for cellular responses is critical for advancing strategies in orthopedic bioreactor-based bone tissue engineering. This study developed a poly (sorbitol sebacate) (PSS) filmscaffold with a sorbitol-to-sebacic acid molar ratio of 1:4.
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January 2025
Technical and Macromolecular Chemistry, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany.
Self-assembled DNA origami lattices on silicon oxide surfaces have great potential to serve as masks in molecular lithography. However, silicon oxide surfaces come in many different forms and the type and history of the silicon oxide has a large effect on its physicochemical surface properties. Therefore, we here investigate DNA origami lattice formation on differently fabricated SiO films on silicon wafers after wet-chemical oxidation by RCA1.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, China.
Nitrogen-containing organic compounds (NOCs) in frost serve as a critical pathway for atmospheric nitrogen deposition, significantly impacting the biogeochemical cycles of nitrogen. However, the molecular characteristics of NOCs in frost and their deposition fluxes are scarcely studied. In this work, frost samples, collected in rural Northeast China in the winter of 2023, were analyzed using nontargeted ultrahigh performance liquid chromatography-orbitrap mass spectrometry (UHPLC-Orbitrap MS) to reveal their content in nitrogen-containing organic compounds (NOCs) and explore their wet deposition fluxes.
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