As a result of systematic study on heavy minerals in soils at city and town areas and their surroundings, cinnabar was discovered for the first time in areas of Hg anomalies in China, and it was found that the distrib...As a result of systematic study on heavy minerals in soils at city and town areas and their surroundings, cinnabar was discovered for the first time in areas of Hg anomalies in China, and it was found that the distribution of cinnabar was basically coincident in scope with that of Hg anomalies, showing that Hg anomalies were'closely related to cinnabar. This finding provides a theoretical basis for a verification of Hg anomalies in soils in city and town areas and their surroundings, as well as evaluation of its ecological effects, and is significant to revealing the occurrence modes and origin of Hg in soils.展开更多
Thirty-nine deep subsurface soils(150—180 cm depth) near the outskirts of Beijing were investagated. The concentrations including n-alkanes from C_ 13 to C_ 36, pristane and phytane were in the range of 0.60 to 170...Thirty-nine deep subsurface soils(150—180 cm depth) near the outskirts of Beijing were investagated. The concentrations including n-alkanes from C_ 13 to C_ 36, pristane and phytane were in the range of 0.60 to 170.10 μg/g, with a median value of 4.26. Carbon preference index values for n-alkanes ranged from 1.08 to 2.98, with a median value of 1.48. The percentage contribution of “wax' n-alkanes was in the range of 6.03%—46.22%. A predominance of odd/even carbon n-alkanes and unresolved complex mixtures with different shapes and ranges were frequently observed. Factor analysis reduced the data set into three principal components and confirming contributions from low(19.58%), medium(20.49%) molecular weight species and long-chain n-alkanes(43.41%), respectively. Molecular biomarkers such as pristane, phytane, hopanes and steranes were detected. Based on the principal component analysis, the concentration profiles and molecular markers, it was found that the aliphatic hydrocarbons were from both biogenic and anthropogenic sources.展开更多
文摘As a result of systematic study on heavy minerals in soils at city and town areas and their surroundings, cinnabar was discovered for the first time in areas of Hg anomalies in China, and it was found that the distribution of cinnabar was basically coincident in scope with that of Hg anomalies, showing that Hg anomalies were'closely related to cinnabar. This finding provides a theoretical basis for a verification of Hg anomalies in soils in city and town areas and their surroundings, as well as evaluation of its ecological effects, and is significant to revealing the occurrence modes and origin of Hg in soils.
基金The National Basic Research Program(973) of China(No. G1999045707)
文摘Thirty-nine deep subsurface soils(150—180 cm depth) near the outskirts of Beijing were investagated. The concentrations including n-alkanes from C_ 13 to C_ 36, pristane and phytane were in the range of 0.60 to 170.10 μg/g, with a median value of 4.26. Carbon preference index values for n-alkanes ranged from 1.08 to 2.98, with a median value of 1.48. The percentage contribution of “wax' n-alkanes was in the range of 6.03%—46.22%. A predominance of odd/even carbon n-alkanes and unresolved complex mixtures with different shapes and ranges were frequently observed. Factor analysis reduced the data set into three principal components and confirming contributions from low(19.58%), medium(20.49%) molecular weight species and long-chain n-alkanes(43.41%), respectively. Molecular biomarkers such as pristane, phytane, hopanes and steranes were detected. Based on the principal component analysis, the concentration profiles and molecular markers, it was found that the aliphatic hydrocarbons were from both biogenic and anthropogenic sources.
