Kidd P S, Domínguez-Rodríguez M J, Díez J, Monterroso C
Instituto de Investigaciones Agrobiológicas de Galicia, Consejo Superior de Investigaciones Científicas, Santiago de Compostela E-15782, Spain.
Chemosphere. 2007 Jan;66(8):1458-67. doi: 10.1016/j.chemosphere.2006.09.007. Epub 2006 Nov 15.
Amendment of agricultural soils with municipal sewage sludges provides a valuable source of plant nutrients and organic matter. Nevertheless, addition of heavy metals and risks of eutrophication continue to be of concern. Metal behaviour in soils and plant uptake are dependent on the nature of the metal, sludge/soil physico-chemical properties and plant species. A pot experiment was carried out to evaluate plant production and heavy metal uptake, soil heavy metal pools and bioavailability, and soil P pools and possible leaching losses, in agricultural soils amended with sewage sludge for at least 10 years (F20) compared to non-amended soils (control). Sewage sludge application increased soil pH, N, Olsen-extractable-P, DOC and exchangeable Ca, Mg and K concentrations. Total and EDTA-extractable soil concentrations of Cu and Zn were also significantly greater in F20, and soil metal (Cu, Mn and Zn) and P fractionation altered. Compared to the control, in F20 relative amounts of acid-extractable (Mn, Zn), reducible (Mn, Zn) and oxidisable (Cu, Zn) metal fractions were greater, and a dominance of inorganic P forms was observed. Analyses of F20 soil solutions highlighted risks of PO4 and Cu leaching. However, despite the observed increases in metal bioavailability sewage sludge applications did not lead to an increase in plant shoot concentrations (in wild plants or crop species). On the contrary, depending on the plant species, Mn and Zn tissue concentrations were within the deficiency level for most plants.
用城市污水污泥改良农业土壤可提供宝贵的植物养分和有机物质来源。然而，重金属的添加以及富营养化风险仍然令人担忧。土壤中金属的行为和植物对金属的吸收取决于金属的性质、污泥/土壤的物理化学性质以及植物种类。进行了一项盆栽试验，以评估在至少10年用污水污泥改良的农业土壤（F20）与未改良土壤（对照）相比，植物产量和重金属吸收、土壤重金属库和生物有效性，以及土壤磷库和可能的淋失损失。施用污水污泥提高了土壤pH值、氮、 Olsen可提取磷、溶解性有机碳以及交换性钙、镁和钾的浓度。F20中铜和锌的土壤总浓度和EDTA可提取浓度也显著更高，并且土壤金属（铜、锰和锌）和磷的形态发生了变化。与对照相比，F20中酸可提取（锰、锌）、可还原（锰、锌）和可氧化（铜、锌）金属形态的相对含量更高，并且观察到无机磷形态占主导地位。对F20土壤溶液的分析突出了磷酸根和铜淋失的风险。然而，尽管观察到金属生物有效性增加，但施用污水污泥并未导致植物地上部分浓度（野生植物或作物品种）增加。相反，根据植物种类的不同，大多数植物中锰和锌的组织浓度处于缺乏水平。
