Page 91 - 2017地大报告电子书

环境学院发展报告

seasonality of floods and extreme precipitation was subject to spatial heterogeneity in northern

Guangdong. Similar changing patterns of peak floods and extreme precipitation were found in
coastal regions; (2) significant increasing/decreasing seasonality, but no confirmed spatial

patterns, were observed for peak floods and extreme precipitation. Peak floods in northern
Guangdong province had decreasing variability, but had larger variability in coastal regions; (3)

tropical cyclones had remarkable impacts on extreme precipitation changes in coastal regions of
southeastern China, and peak floods as well. The

landfalling of tropical cyclones was decreasing and
concentrated during June-September; this is the

major reason for earlier but enhanced seasonality
of peak floods in coastal regions. This study sheds

new light on flood behavior in coastal regions in a
changing environment. (C) 2017 Elsevier B.V. All

rights reserved.
论文链接：https://doi.org/10.1016/

j.jhydrol.2017.07.039

23. Effect of reduced humic acid on the transport of ferrihydrite nanoparticles
under anoxic conditions
作 者 : Liao, Peng; Li, Wenlu; Wang, Dengjun; 等 .

WATER RESEARCH 卷 : 109 页 : 347-357 出版年 : FEB 1 2017
摘 要：Humic acid (HA) occurs ubiquitously in the subsurface environments and is

well-known to play a critical role in the fate and transport of ferrihydrite nanoparticles (NPs)
and NPs-associated contaminants. Under anoxic conditions, HA can readily be reduced by

microorganisms or geochemical reducing species, and the mechanisms and kinetics of ferrihydrite
reduction by reduced HA (HAred) are well-documented; however, the role of these redox

reactions on the transport of ferrihydrite NPs is largely underestimated. This study provides new
knowledge regarding the role of HA (both reduced HA (HAred) and oxidized HA (HAox)) of

environmentally relevant concentrations (0–50 mg C/L) on the transport of ferrihydrite NPs
in anoxic sand columns. Our findings show that, regardless of the redox state, the presence of

a low concentration of HA (3 mg C/L) inhibited ferrihydrite NP's transport due to enhanced
aggregation (and deposition) between positively charged ferrihydrite NPs and negatively charged

HA molecules. In contrast, higher HA (both HAred and HAox) concentration ( ≥ 10 mg C/

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