In this study, exchange fluxes and Hg isotope fractionation during water-atmosphere Hg(0) exchange were investigated at three lakes in China. Water-atmosphere exchange was overall characterized by net Hg(0) emissions, with lake-specific mean exchange fluxes ranging from 0.9 to 1.8 ng m h, which produced negative δHg (mean: -1.61 to -0.03‰) and ΔHg (-0.34 to -0.16‰) values. Emission-controlled experiments conducted using Hg-free air over the water surface at Hongfeng lake (HFL) showed negative δHg and ΔHg in Hg(0) emitted from water, and similar values were observed between daytime (mean δHg: -0.95‰, ΔHg: -0.25‰) and nighttime (δHg: -1.00‰, ΔHg: -0.26‰). Results of the Hg isotope suggest that Hg(0) emission from water is mainly controlled by photochemical Hg(0) production in water. Deposition-controlled experiments at HFL showed that heavier Hg(0) isotopes (mean εHg: -0.38‰) preferentially deposited to water, likely indicating an important role of aqueous Hg(0) oxidation played during the deposition process. A ΔHg mixing model showed that lake-specific mean emission fluxes from water surfaces were 2.1-4.1 ng m h and deposition fluxes to water surfaces were 1.2-2.3 ng m h at the three lakes. Results from the this study indicate that atmospheric Hg(0) deposition to water surfaces indeed plays an important role in Hg cycling between atmosphere and water bodies.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.est.3c01273 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Methane emissions from the riverine sandy wetlands on the Mongolia Plateau.
Environ Monit Assess
December 2024
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing, 100093, China.
Methane (CH) processes and fluxes have been widely investigated in low-latitude tropical wetlands and high-latitude boreal peatlands. In the mid-latitude Mongolia Plateau, however, CH processes and fluxes have been less studied, particularly in riverine wetlands. In this study, in situ experiments were conducted in the riverine sandy wetlands of the Mongolia Plateau to gain a better understanding of CH emissions and their influencing mechanisms.
View Article and Find Full Text PDFIntact Australian Sphagnum peatland is a strong carbon sink.
Sci Total Environ
December 2024
Applied Chemistry and Environmental Science, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia. Electronic address:
Peatlands are important global stores of carbon. However, peatland disturbance, including climate change, can cause stored carbon to be released, shifting peatlands from net carbon sinks to net carbon sources. Yet, there is a paucity of data on the carbon cycling of Australian peatlands from which to inform effective management of the peatland carbon store.
View Article and Find Full Text PDFRewetted bogs with high water levels (WL) and mire-specific vegetation are crucial carbon (C) sinks, but their function might be threatened by tree encroachment, a phenomenon widespread in the northern hemisphere that often coincides with low WL. This might impact C cycling both at the ecosystem and microform scale in multiple ways, but so far, data are lacking. We established two sites in the same former peat extraction area, one showing permanently high WL and mire-specific vegetation (open site, OS), while the other one has more fluctuating WL and a dense birch ( Ehrh.
View Article and Find Full Text PDFDirected coordination of C/N-termini of cyano group in metal hexacyanoferrates to efficient palladium recovery: Enhanced adsorption affinity and selectivity.
Environ Res
December 2024
Yanshan Earth Critical Zone and Surface Fluxes Research Station, College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address:
N-termini Cyano group (CN) in metal hexacyanoferrates (MHCF) have been identified as specific-affinity sites for palladium (Pd), but C-termini CN do not effectively serve as Pd adsorption sites due to their stronger bonds with the metal ligands (M), which reduces the activity and density of CN. Herein, the optimization of directional coordination of cyano group C/N-termini by modulating the electronic structure of the M (Fe, Co, and Ni) in MHCF was investigated to reinforce the Pd recovery. Spectroscopic analyses and DFT calculations revealed that NiHCF exhibited N-site mono-coordination, whereas CoHCF displayed C-site mono-coordination due to spin-exchange interactions, leading to the strengthened N-Co bonds and weakened Fe-C bonds.
View Article and Find Full Text PDFAnalysis of the Dynamics of a Complex, Multipathway Reaction: Insulin Dimer Dissociation.
J Phys Chem B
December 2024
Department of Chemistry, the University of Chicago, Chicago, Illinois 60637, United States.
The protein hormone insulin forms a homodimer that must dissociate to bind to its receptor. Understanding the kinetics and mechanism of dissociation is essential for the rational design of therapeutic analogs. In addition to its physiological importance, this dissociation process serves as a paradigm for coupled (un)folding and (un)binding.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!