灌溉水质对污灌区土壤重金属含量的影响分析

利用统计学方法和空间分析,对鞍山宋三灌区稻田土壤重金属含量进行了分析研究。结果表明,利用工业废水进行灌溉的稻田,土壤环境质量明显低于利用河水和城市生活污水进行灌溉的区域,土壤重金属Cd和Hg分别超标1.8倍和2.2倍。空间分析结果显示,污灌区土壤重金属含量的空间差异明显,6种重金属污染物空间分布的峰值均出现在工业废水进行灌溉的区域。由此所得结论是:工业废水中的污染物质对农田土壤环境影响明显,应避免直接用于农田灌溉;在农田土壤环境保护工作中,在对重点污染物进行分析的同时,应加强对重点区域的监测。

Impact of Irrigation Water Quality on Heavy Metals' Concentrations in Surface Soil of Paddy Field

The spatial distribution characters of different heavy metals in irrigated field soil and the relationship between the irrigating water and agricultural soil environment were illustrated through statistical and spatial analysis. Plough layer soil in paddy field and irrigating water were sampled from Songsan irrigation region, Anshan city, where the paddy field irrigated with industry wastewater and urban sewage more than fifty years. Statistic data showed that soil environment quality of paddy field irrigated with industry wastewater was notably worse than that irrigated with river water and urban sewage, and the concentrations of Cd and Hg in paddy soil irrigated with industry wastewater were 1.8 and 2.2 times of environmental quality standards respectively (GB15618-1995). Space analysis indicated that heavy metals' concentrations distinctly varied with different regions in the irrigated area, and the peak values of all six heavy metals' contours appeared in the middle area irrigated with industry wastewater. Therefore, the impact of irrigate water on paddy field soil were identified. Contaminations in industry wastewater would pollute the soil environment significantly and should avoid being used in agriculture irrigation directly. As well as the important pollutants, key area of irrigation region should be monitored especially for the spatial difference of heavy metals in paddy soil.