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A review of source tracking techniques for fine sediment within a catchment
Guan, Zhuo,Tang, Xiang-Yu,Yang, Jae E.,Ok, Yong Sik,Xu, Zhihong,Nishimura, Taku,Reid, Brian J. Springer-Verlag 2017 Environmental geochemistry and health Vol.39 No.6
<P>Excessive transport of fine sediment, and its associated pollutants, can cause detrimental impacts in aquatic environments. It is therefore important to perform accurate sediment source apportionment to identify hot spots of soil erosion. Various tracers have been adopted, often in combination, to identify sediment source type and its spatial origin; these include fallout radionuclides, geochemical tracers, mineral magnetic properties and bulk and compound-specific stable isotopes. In this review, the applicability of these techniques to particular settings and their advantages and limitations are reviewed. By synthesizing existing approaches, that make use of multiple tracers in combination with measured changes of channel geomorphological attributes, an integrated analysis of tracer profiles in deposited sediments in lakes and reservoirs can be made. Through a multi-scale approach for fine sediment tracking, temporal changes in soil erosion and sediment load can be reconstructed and the consequences of changing catchment practices evaluated. We recommend that long-term, as well as short-term, monitoring of riverine fine sediment and corresponding surface and subsurface sources at nested sites within a catchment are essential. Such monitoring will inform the development and validation of models for predicting dynamics of fine sediment transport as a function of hydro-climatic and geomorphological controls. We highlight that the need for monitoring is particularly important for hilly catchments with complex and changing land use. We recommend that research should be prioritized for sloping farmland-dominated catchments.</P>
Chai Shutong,Zheng Ziyun,Liu Yani,Liang Yanhui,Yang Hong,Chen Jie,Bai Hongjuan,Yang Guan-e 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.2
Background Rhodopseudomonas palustris had the eff ect of adsorbing and removing lead ions. Metabolomics is a comprehensive analysis based on several metabolites or biomarkers. Objective The paper aimed to investigate the restorative eff ect and the potential mechanisms of R. palustris in rats with the lead exposure model using 1 H-NMR metabolomics. Results Nine endogenous metabolites from rat plasma and 13 endogenous metabolites from rat urine were identifi ed as potential biomarkers of the symptoms of lead poisoning. The changes of metabolites levels in the plasma included lower levels of valine, acetoacetate, and N-acetyl-glycoprotein and a higher concentration of lactate, acetate, creatine, threonine, glutamine, and asparagine in model group compared with control group. Furthermore, increased citrate, succinate, dimethylamine, pyruvate, acetoacetate, α -oxoglutarate and asparagine, accompanied by decreased LDL/VLDL, taurine, creatinine, glucose and hippurate levels were observed in the model group compared with the control group in the urine. Biochemical parameters and histopathology examination dovetailed well with the metabolomics data. Treatment with R. palustris at a certain degree returned the levels of these metabolites to normal levels. Plasma and urine metabolomic analysis showed changes associated with energy metabolism, amino acids and fatty acid metabolism of lead exposure rats. Conclusion The eff ects of removing lead ions of R. palustris in rats with lead exposure were confi rmed. This research demonstrated that 1 H-NMR-based metabolomics was a promising tool to identify potential biomarkers and unravel protective eff ect mechanisms of R. palustris in lead poisoning rats.