TY - JOUR
T1 - A magnetic record of heavy metal pollution in the Yangtze River subaqueous delta
AU - Dong, Chenyin
AU - Zhang, Weiguo
AU - Ma, Honglei
AU - Feng, Huan
AU - Lu, Honghua
AU - Dong, Yan
AU - Yu, Lizhong
PY - 2014/4/1
Y1 - 2014/4/1
N2 - The rapid industrial development in the Yangtze River watershed over the last several decades has drawn great attention with respect to heavy metal pollution to the Yangtze River estuary and nearby coastal areas. In this study, a 236cm long sediment core was retrieved from the Yangtze River subaqueous delta (122°36' E, 31°00' N) in 2008 and analyzed for magnetic properties and geochemical compositions to investigate heavy metal pollution history. The activity of 137Cs peaked at depth 140cm, with a broad plateau between 120cm and 140cm, suggesting an average sedimentation rate of 3.11cmyr-1 for the upper 140cm layer. Magnetic susceptibility (χ), saturation isothermal remanent magnetization (SIRM), anhysteretic remanent magnetization (χARM) and heavy metal enrichment factors (EF) all showed an upward increase trend above depth 140cm, suggesting that increased ferrimagnetic mineral concentration was accompanied by heavy metal enrichment in the sediment. Geochemical and granolumetric analyses showed that sediment sources and particle sizes played minor roles in the variations of magnetic properties. The effect of diagenesis, which can lead to the selective removal of magnetic minerals, was noticeable in the lower part of the core (140-236cm). Co-variation between magnetic properties (χ, SIRM and χARM) and EF of Cu and Pb suggests that the elevated ferrimagnetic mineral concentration can be used as an indicator of heavy metal pollution in the reconstruction of environmental changes in estuarine and coastal settings.
AB - The rapid industrial development in the Yangtze River watershed over the last several decades has drawn great attention with respect to heavy metal pollution to the Yangtze River estuary and nearby coastal areas. In this study, a 236cm long sediment core was retrieved from the Yangtze River subaqueous delta (122°36' E, 31°00' N) in 2008 and analyzed for magnetic properties and geochemical compositions to investigate heavy metal pollution history. The activity of 137Cs peaked at depth 140cm, with a broad plateau between 120cm and 140cm, suggesting an average sedimentation rate of 3.11cmyr-1 for the upper 140cm layer. Magnetic susceptibility (χ), saturation isothermal remanent magnetization (SIRM), anhysteretic remanent magnetization (χARM) and heavy metal enrichment factors (EF) all showed an upward increase trend above depth 140cm, suggesting that increased ferrimagnetic mineral concentration was accompanied by heavy metal enrichment in the sediment. Geochemical and granolumetric analyses showed that sediment sources and particle sizes played minor roles in the variations of magnetic properties. The effect of diagenesis, which can lead to the selective removal of magnetic minerals, was noticeable in the lower part of the core (140-236cm). Co-variation between magnetic properties (χ, SIRM and χARM) and EF of Cu and Pb suggests that the elevated ferrimagnetic mineral concentration can be used as an indicator of heavy metal pollution in the reconstruction of environmental changes in estuarine and coastal settings.
KW - Diagenesis
KW - Heavy metal pollution
KW - Magnetic properties
KW - Particle size
KW - Yangtze River subaqueous delta
UR - https://www.scopus.com/pages/publications/84893106968
U2 - 10.1016/j.scitotenv.2014.01.020
DO - 10.1016/j.scitotenv.2014.01.020
M3 - 文章
C2 - 24480666
AN - SCOPUS:84893106968
SN - 0048-9697
VL - 476-477
SP - 368
EP - 377
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -