污灌稻田生态系统重金属含量分布调查

对鞍山某污灌区稻田土壤、糙米以及灌溉水中重金属Cd、As、Hg、Pb含量进行了采样和分析.结果表明：研究区土壤重金属含量总体上低于现选择土壤环境质量标准所规定的上限.但由于受灌溉水质的影响,灌区中部利用工业废水进行灌溉的区域土壤表层中Cd和Hg含量分别为1.08mg/kg和1.03mg/kg,糙米中Hg含量为0.2mg/kg,均接近或超出相应的国家标准规定的上限,说明灌溉水中的重金属含量水平对土壤和粮食中重金属含量的影响明显,并有可能造成粮食重金属含量超标.因此,工业废水对土壤环境质量和稻米品质的影响较大,应避免直接用于农田灌溉.

Investigation on Content Distribution of Heavy Metals in Ecosystem of Sewage Irrigated Paddy Rice Field

The contents of Cd, As, Hg and Pb of soil,irrigating water and rice corn in the irrigated areas of Anshan City irrigated with sewage water were investigated. The results showed that the contents of four kinds of heavy metal in the soil surface accorded with the national standard for the soil and environment quality generally. Impacted by the quality of irrigating water, the heavy metal contents of the soil and rice corn in the middle area were higher than that in the southern and northern areas,with the 1.08mg/kg Gd, 1.03mg/kg Hg in soil and 0. 2mg,/kg Hg in rice corn respectively. These reached or were beyond the relative item of national standard for the soil and environment quality. The contents of heavy metals in soil and rice corn were obviously impacted by the irrigating water quality. It was suggested to avoid using the industrial sewage water as agricultural irrigation water directly.