ABSTRACT

An attempt has been made to assess the geoavailability of heavy metals in polluted soils using short sequential fractionation schemes. For this purpose, 25 composite soil samples were collected from various locations (across India) of which had a history of receiving sewage sludge, municipal solid waste, polluted river water and industrial effluents. Four composite soil samples were also collected from adjacent fields which had not received contaminated amendments. Zinc (Zn), copper (Cu), nickel (Ni), lead (Pb) and cadmium (Cd) were extracted from the soil solution plus exchangeable, carbonate bound, Fe and Mn oxides bound, and organic matter bound fractions. Copper (53.0%) was largely adsorbed by the organic fractions, while a significant amount of Zn (56.6%), Ni (78.4%), Pb (57.4%), and Cd (59.7%) was extracted from the Fe/Mn oxide bound fraction. Regression analysis revealed that water-soluble plus exchangeable pool of Zn, Cu, Ni, Pb and Cd contributed positively towards the uptake of these elements by spinach and wheat under pot experiment. Behaviour, transport and the ultimate fate of heavy metals in the soil environment depend largely on their association with different geochemical fractions of the soil which is related to the mineralogical origin of the metals.

摘要

已经尝试使用短期顺序分馏方案评估污染土壤中重金属的地质利用度。为此，从不同地点（印度各地）收集了25个复合土壤样本，这些样本具有接收污泥，城市固体废物，污染的河水和工业废水的历史。还从没有收到污染修正物的相邻田地中收集了四个复合土壤样品。从土壤溶液中提取锌（Zn），铜（Cu），镍（Ni），铅（Pb）和镉（Cd），以及可交换的碳酸盐键，Fe和Mn氧化物键以及有机物键合馏分。铜（53.0％）被大部分有机物吸附，而大量的锌（56.6％），镍（78.4％），铅（57.4％）和镉（59。从Fe / Mn氧化物结合级分中提取7％）。回归分析表明，在盆栽实验中，水溶性和可交换的锌，铜，镍，铅和镉的交换池对菠菜和小麦对这些元素的吸收有积极贡献。土壤环境中重金属的行为，运输和最终命运在很大程度上取决于它们与土壤中不同地球化学部分的关系，而这些部分与金属的矿物学起源有关。