The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heav...The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heavy metals including As, Cr, Cd, Cu, Ni, Pb, and Zn. The results showed that these metals are largely accumulated in the top 0 3 meter layer of the river sediment.Despite the contamination, heavy metal concentrations in solution are increased in some locations only. The only exception is Zn whose concentrations are extremely high both in solution and in the top layer sediment. The top layer sediment appears to have reached almost its sorption capacity with respect to aqueous Zn. The extent of contamination is in the sequence of Zn>Cu>Pb>As>Cd. It is speculated that Cu distribution has been significantly affected by its binding to organic matter in the top layer sediment. Based on Pb distribution in both water and sediment, it is suggested that Pb transport in the canal is associated with colloids or particles suspended in water. The study showed that the top layer sediment in the Grand Canal serves as a sink to anthropogenic contaminants consisting of heavy metals as well as organic compounds.展开更多
1793年,马戛尔尼使团成功到达中国,觐见了乾隆皇帝,这是英国政府历史上首次访华。1797年,《英使谒见乾隆纪实》一书面世,这是英国使团首次访华的官方记录。书中有一幅A sketch of a journey from Zhe-Hol in Tartary by land to Pekin a...1793年,马戛尔尼使团成功到达中国,觐见了乾隆皇帝,这是英国政府历史上首次访华。1797年,《英使谒见乾隆纪实》一书面世,这是英国使团首次访华的官方记录。书中有一幅A sketch of a journey from Zhe-Hol in Tartary by land to Pekin and from thence by water to Hang-Tchoo-Foo in China(《从热河经陆路到北京及从北京经水路到杭州府之旅程图》),是典型的中国内河航线图。本文考察了该图的制图背景、版本源流、地理要素和信息表达等内容,说明马戛尔尼使团首次访华绘制的大运河图是英国为了开拓与清政府的自由贸易而试图开辟英中海上航线的附加成果,也是英国为了进行殖民扩张、开拓世界市场而展开全球航行的一部分。展开更多
文摘The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heavy metals including As, Cr, Cd, Cu, Ni, Pb, and Zn. The results showed that these metals are largely accumulated in the top 0 3 meter layer of the river sediment.Despite the contamination, heavy metal concentrations in solution are increased in some locations only. The only exception is Zn whose concentrations are extremely high both in solution and in the top layer sediment. The top layer sediment appears to have reached almost its sorption capacity with respect to aqueous Zn. The extent of contamination is in the sequence of Zn>Cu>Pb>As>Cd. It is speculated that Cu distribution has been significantly affected by its binding to organic matter in the top layer sediment. Based on Pb distribution in both water and sediment, it is suggested that Pb transport in the canal is associated with colloids or particles suspended in water. The study showed that the top layer sediment in the Grand Canal serves as a sink to anthropogenic contaminants consisting of heavy metals as well as organic compounds.
文摘1793年,马戛尔尼使团成功到达中国,觐见了乾隆皇帝,这是英国政府历史上首次访华。1797年,《英使谒见乾隆纪实》一书面世,这是英国使团首次访华的官方记录。书中有一幅A sketch of a journey from Zhe-Hol in Tartary by land to Pekin and from thence by water to Hang-Tchoo-Foo in China(《从热河经陆路到北京及从北京经水路到杭州府之旅程图》),是典型的中国内河航线图。本文考察了该图的制图背景、版本源流、地理要素和信息表达等内容,说明马戛尔尼使团首次访华绘制的大运河图是英国为了开拓与清政府的自由贸易而试图开辟英中海上航线的附加成果,也是英国为了进行殖民扩张、开拓世界市场而展开全球航行的一部分。
