『Abstract
Metals in lacustrine sediment have both anthropogenic and natural
sources. Because of intensified human activities, the anthropogenic
input of metal elements has exceeded the natural variability.
How to distinguish the anthropogenic sources in lake sediments
is one of the tasks in environmental management. The authors present
a case study, which combined the geochemical and statistical methods
to distinguish the anthropogenic sources from the natural background.
A 56 cm core (core DJ-5) was collected from Dongjiu Lake, Taihu
Lake catchment, China. The concentration distributions of Al,
Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr,
Ti, V and Zn in core DJ-5 indicated that Dongjiu Lake had serious
Cd pollution, and the concentrations of Cr, Cu, Pb, Mn and Zn
had also exceeded the Chinese State Standards of Soil Environmental
Quality in the upper layer of the core. Using al as a reference
element, the other metals were normalized and compared with their
baselines to calculate the enrichment factors (EFs). The principal
component analysis(PCA) of metal concentrations was performed
using ViSta6.4. The results of EFs and PCA indicated that the
concentration variations of Cd, Cu, Pb, Mn and Zn were mainly
caused by the anthropogenic sources, and the concentration variations
of Cr and Ni were influenced by both the anthropogenic and natural
factors, while the other metals were mainly derived from the natural
sources. Intensified human activities within the lake catchment
area resulted in the increase of heavy metal inputs directly and
the acceleration of erosion which caused other metal elements
to deposit in the aquatic environment. The results of this work
will be useful in probing changes forced by humans in the lake
environment and in adjusting human activity in restoring the lake
environment.
Keywords: Metal element; Principal component analysis; Enrichment
factors; Human activity; Anthropogenic sources; Dongjiu Lake;
China』
Introduction
General description of the research area
Materials and methods
Sampling
Elementary analysis
Data analysis
Results and discussion
Element concentrations of the sediments in Core DJ-5
The PCA analysis using metal element concentrations of sediments
in core DJ-5
The enrichment factors of metal elements in sediments of Core
DJ-5
Conclusions
Acknowledgments
References