长株潭城市群土壤pH与重金属污染的研究

The Correlation of Heavy Metal with pH in Soils from Changsha-Zhuzhou-Xiangtan Urban Agglomeration

为了研究土壤样品pH和土壤中重金属含量的相关关系，对长株潭城市群60个土壤样品中pH、有机质含量和重金属含量进行分析。结果表明：长株潭城市群的60个采样点中，13．3％的土壤样pH〈5．0，35％的土壤样品的pH在5．0-6．5之间，41．7％的土壤样品pH在6．5-7．5之间，10％的土壤样品pH在7．5-8．5之间，无强碱性样品。长株潭地区不同土壤pH范围的重金属平均含量不同，随着土壤pH由强酸性、酸性到中性的升高，重金属含量显著提高，但当pH超过7．5，碱性土壤中的重金属含量呈下降趋势。

In order to investigate the correlations of heavy metal with contents and heavy metal concentration of 60 soil samples collected from pH in soils, the pH, organic matter Changsha-Zhuzhou-Xiangtan urban agglomeration were analyzed. The results showed that, the pH of 13.3% samples were lower than 5.0, 35% of samples were 5.0-6.5, 41.7% of samples were 6.5-7.5 and 10% of samples were 7.5-8.5. In conclusion, different mean heavy metal concentrations in soil samples were achieved during various pH ranges. The heavy metals contents increased significantly with the pH of soils increased from strong acidic, acidic soils to neutral soils. However, the heavy metal contents decreased in alkaline soil samples when the pH over 7.5.