[Pollution of Heavy Metals in Topsoil of Remote Mountainous Areas in Western Yunnan-Guizhou Plateau].

Heavy metals from anthropogenic emissions have had a negative impact on the ecological environment in remote regions. A total of 69 topsoil samples were collected from 13 remote mountainous areas in the western Yunnan-Guizhou Plateau at altitudes of 2 563-4 037 m, and the concentrations of ten heavy metals in the samples were determined. Enrichment characteristics and pollution sources of heavy metals in topsoil were discussed by referencing the enrichment factor （EF）, positive matrix factorization （PMF）, and Pb isotopes.

[Critical Review on Heavy Metal Contamination in Urban Soil and Surface Dust].

With the rapid urbanization and industrialization, heavy metal contamination in urban soil and surface dust has received particular attention due to its negative effects on the eco-environment and human health. Contamination and spatio-temporal characteristics, contamination sources, and source apportionment methods, as well as the ecological and health risks of heavy metals in urban soil and surface dust were reviewed. The knowledge gaps in current research and prospects of future works were proposed.

[Spatial-temporal Variations and Pollution Assessment of Heavy Metals in Sediments of Qionghai Lake in Xichang City].

Based on the analysis of the total concentrations of 10 metals in the sediment core and total concentrations and chemical fractions of seven metals in the surface sediments of Qionghai Lake in Xichang City, Sichuan Province, the spatial-temporal characteristics of metal accumulation and pollution over the past century and the potential ecological risk of metals in surface sediments were studied. Before the 1970s, metal concentrations in the sediment core were stable. The total concentrations of Al, Fe, K, and Cr in the sediment core exhibited visible peaks in the 1970s, which were related to the enhanced input of fine-grained topsoil caused by increasing precipitation, lake reclamation, and deforestation.

[Historical Trends of Atmospheric Trace Metal Pollution in Northern Guizhou Province as Reconstructed from Alpine Lake Sediments].

Atmospheric trace metal pollution is a striking environmental problem globally. Because of the limitations in monitoring data, our knowledge of the historical processes and sources of atmospheric trace metal pollution in China and its influence on remote terrestrial environmental quality is limited. The historical variations in atmospheric trace metal (Cd, Cr, Cu, Hg, Ni, Pb, and Zn) pollution during the past 400 years in the Fanjing Mountain area, northern Guizhou Province were studied by analyzing the metal concentrations and Pb isotopes in lake sediments.

[Contamination and Potential Ecological Risk Assessment of Heavy Metals in the Sediments of Yilong Lake, Southwest China].

The concentrations of Al, Ti, As, Cd, Cr, Cu, Ni, Pb, Zn, and Hg and chemical speciation of Cd, Cr, Cu, Ni, Pb, and Zn in four short cores sampled from the Yilong Lake, Yunnan Province were analyzed. The vertical and spatial features in the pollution levels and potential ecological risks of heavy metals in the sediments were studied. Except for the wide concentration ranges of Cd, the metals in the sediments showed narrow variations in their concentrations with coefficients of variation less than 0.

[Spatio-temporal Variations, Contamination and Potential Ecological Risk of Heavy Metals in the Sediments of Chenghai Lake].

Heavy metals pollution in the sediments is one of the main factors impacting the water quality and ecosystem health. In this study, concentrations of ten metals in nine sediment cores from the Chenghai Lake were determined. Chronology of a typical core (CH2012) was constructed by the Pb and Cs dating method.

[Assessment and characterization of heavy metals and nutrients in sediments from Taihu Lake].

The concentrations of Zn, Cu, Mn, Cr, Pb, Al, Fe, iron-bound P (Fe-P) and TP in the sediments from Taihu Lake, a eutrophic shallow lake, China, were determined. The results show that the concentrations of heavy metals are higher than those in the earth crust. Particularly, enrichments of Cr and Pb are more conspicuous than other metals.

[Space distribution characteristics and diversity analysis of phosphorus from overlying water and surface sediments in Taihu Lake].

The physi-chemical indexes in the overlying water and surface sediments of Taihu Lake, an eutrophic shallow lake, were determined. Then, the isopleth maps of spatial distribution of each parameter were illustrated. The results show that the concentrations of SRP, TP and TN in the overlying water and TOC, TN and TP as well as phosphorus fractions in surface sediments exhibit distinct diversity in spatially.

Assessment of nutrients and heavy metals enrichment in surface sediments from Taihu Lake, a eutrophic shallow lake in China.

Concentrations of the nutrients (TN and TP), phosphorus fractions and heavy metals (Co, Cr, Cu, Mn, Ni, Pb, Sr, Ti, V, Zn and Hg) in 40 surface sediment samples collected from Taihu Lake, a eutrophic shallow lake in China, were determined. The results showed that the northwest region of the lake possessed higher concentrations of TN and TP, as well as the similar spatial distribution trend in the water column. This should be related to excessive anthropogenic input from industrial effluents and domestic sewage in surrounding areas.

[Chemical fractionation and pollution characteristics of heavy metals in the sediment of Nansihu Lake and its main inflow rivers, China].

Chemical forms of Cr, Cu, Mn, Ni, Pb and Zn in the surface sediments of Nansihu Lake and its main inflow rivers are determined by the BCR sequential extraction method. The chemical fractionation composition characteristics, pollution state and potential ecological effects of the heavy metals are discussed. Cr, Cu, Ni and Zn in the sediments of Sihe River, Jinghang Canal, Zhuzhaoxin River, Guangfu River, south area of the Upper Lakes, and Down Lakes mainly exist in residual fraction, which account for 80% - 90% of their content, mainly reflecting the natural characteristics of the heavy metals; but for the sediment of Old Canal, Guangfu River estuary, Baima River, nearly 80% of Cr, Cu, Ni and Zn exist in extractable fractions due to human pollution, especially with high oxidizable and acid extractable fractions content.