摘要
铅冶炼过程向环境释放重金属和SO2污染物,然而,冶炼企业对附近土壤酸碱性和电导率的影响以及这些土壤性质与重金属有效性的关系研究不足。本研究在华北平原某铅冶炼厂以北农田采集0～20 cm耕层的土壤样品,分析土壤pH值和电导率与DTPA态重金属的关系。结果表明:冶炼厂附近农田土壤pH值变化范围为7.26～8.63(中值为8.22),电导率变化范围为0.101 5～0.204 5 mS/cm(中值为0.127 2 mS/cm);距离冶炼厂较近处土壤pH值较低、电导率较高;土壤pH值与DTPA态Ni、Cu、Pb、Zn和Cd均呈显著负相关(P<0.05),电导率仅与DTPA态Cd存在显著正相关(P<0.05);因子分析表明,冶炼厂是土壤重金属有效性增加的主要因素,而采样区北端附近的另一污染源是造成土壤电导率增加的主要因素,2个污染源对土壤pH值下降的贡献程度基本相同。说明该铅冶炼厂造成附近农田土壤pH值下降、电导率升高,且重金属有效性增加,但土壤pH值下降并非重金属有效性上升的主要因素。
Lead smelting process release heavy metals and sulfur dioxide into the environment. However, the pH and electrical conductivity （EC） of the soil in the vicinity of lead smelting factory and their relations with heavy metal availability have rarely been studied. Soil samples were collected from farming fields near the north of a lead smelter in the North China Plain and the soi! pH, EC and their relations with DTPA-extraetable heavy metals were analyzed. The results showed that soil pH ranged 7.26 -8.63 （with the median of 8.22）, EC ranged 0. 101 5 - 0. 204 5 mS/era （with the median of 0. 127 2 mS/cm） . Soil samples collected near the smelting factory had lower pH and higher EC, there were significant correlations between soil pH and contents of the DTPA-extractable nickel （Ni）, copper （Cu）, lead （Pb）, zinc （Zn） and cadmium （Cd） （P〈0.05）, EC only had a significant positive correlation with contents of the DTPA-extractable Cd （P 〈 0. 05 ） . Component analysis indicated that the smelting factory was the main reason of enhanced heavy metal availability of soil, another pollution source near the northern edge of the sampled area was the main reason of high EC of the study area, the two pollution sources contributed nearly equally to the soil pH decrease. Those suggested that the lead smelting factory results in the decrease of soil pH, increase of EC and heavy metal availability, however, the lower soil pH was not the main reason of the rising of heavy metal availability of the soil.
出处
《河北农业科学》
2012年第9期71-76,80,共7页
Journal of Hebei Agricultural Sciences
基金
河南省教育厅自然科学研究计划项目(2011A610006)
关键词
冶炼
土壤
PH
电导率
重金属
有效性
Smelting
Soil
pH
Electrical conductivity
Heavy metal
Availability
作者简介
作者简介：李立平（1972-），男，甘肃灵台人，副教授，博士，主要从事土壤与环境科学研究。E—mail：li_lipingcn@yahoo．com.cn.
