College of Resources and Environment Science of Xinjiang University, Urumqi 830046, China.
Key Laboratory of Xinjiang Arid Land Lake Environment and Resource, Xinjiang Normal University, Urumqi830054, China.
Sci Total Environ. 2014 Sep 15;493:1098-111. doi: 10.1016/j.scitotenv.2014.03.087. Epub 2014 Jun 20.
A total of 469 surface soil samples were collected from the Yanqi basin in northwest China and evaluated for levels of ten heavy metals. Multivariate statistical analyses were used to study sources of and map the spatial distribution of heavy metals, as well as determine the relationship between land use types and soil source materials. It was found that: (1) the average amounts of ten heavy metals in the Yanqi basin were all below the national soil environmental quality standards of China (GB15618-1998), but the average amount of Cd, Hg, Mn, Ni, Pb, and Zn all exceeded the heavy metal background levels of soil in Xinjiang, China and exhibited accumulation. The ten heavy metals analyzed in this study can be categorized into four principal components as follows: Principal component 1 was Co, Cr, Mn, Ni, and Zn, and principal component 3 was As and Cu. Both of these originated from a natural geological background. Principal component 2 consisted of Cd and Pb and originated from industrial, agricultural and transportation influences. Principal component 4 consisted of Hg and was due to industrial influences. Our study found that Pb and Zn were a large part in the principal components 1 and 3 and were influenced by a combination of geologic background and human activity. (2) Heavy metals Cd and Hg were at high levels in construction land and farmland, while Co, Cr, Cu, Mn, and Ni were significantly higher in lacustrine deposits than in sandy shale from weathered material, coarse crystalline rock weathered material, and diluvial material. The land use types correlated significantly with the accumulation of Cd and Hg, and the soil parent material was the major factor for the accumulation of As, Co, Cr, Cu, Mn, and Ni. (3) The single element, element integration and the corresponding principal component presented similar spatial patterns of hazardous risk. Following comprehensive assessment of all elements, the high risk regions were found to be located in densely-populated urban areas and western parts of the study area. This was attributed to the higher geological background in the western part and strong human influence in the central part. Research shows that Cd, Hg, Pb, and Zn were locally enriched in the basin and this warrants increased attention.
在中国西北部的焉耆盆地共采集了 469 个表层土壤样本，并对其中的十种重金属进行了评估。采用多元统计分析方法研究了重金属的来源和空间分布，并确定了土地利用类型与土壤源材料之间的关系。结果表明：（1）焉耆盆地十种重金属的平均含量均低于中国国家土壤环境质量标准（GB15618-1998），但 Cd、Hg、Mn、Ni、Pb 和 Zn 的平均值均超过了中国新疆土壤重金属背景值，并表现出积累。本研究分析的十种重金属可分为四个主要成分：第一主成分为 Co、Cr、Mn、Ni 和 Zn，第三主成分为 As 和 Cu，均来源于自然地质背景。第二主成分为 Cd 和 Pb，来源于工业、农业和交通的影响。第四主成分为 Hg，受工业影响。研究发现 Pb 和 Zn 在第一和第三主成分中占很大比例，受地质背景和人类活动的综合影响。（2）建设用地和农田中 Cd 和 Hg 含量较高，而湖相沉积物中 Co、Cr、Cu、Mn 和 Ni 的含量明显高于风化物质砂页岩、粗晶质岩风化物质和洪积物质。土地利用类型与 Cd 和 Hg 的积累显著相关，土壤母质是 As、Co、Cr、Cu、Mn 和 Ni 积累的主要因素。（3）单一元素、元素综合及相应主成分的危险风险空间分布模式相似。对所有元素进行综合评价后，发现高风险区域位于人口密集的城市地区和研究区西部。这归因于西部较高的地质背景和中部较强的人为影响。研究表明，Cd、Hg、Pb 和 Zn 在该盆地局部地区富积，需要引起更多关注。
