不同土壤改良剂对降低重金属污染土壤上水稻糙米铅镉含量的作用  

Effects of Different Types of Soil Amelioration Materials on Reducing Concentrations of Pb and Cd in Brown Rice in Heavy Metal Polluted Paddy Soils

作　　者：王凯荣[1] 张玉烛 胡荣桂[3] 

机构地区：[1]莱阳农学院农业生态与环境健康研究所 [2]湖南省水稻研究所,湖南长沙410125 [3]华中农业大学资源与环境学院,湖北武汉430070

出　　处：《农业环境科学学报》2007年第2期476-481,共6页Journal of Agro-Environment Science

基　　金：农业部农业结构调整重大研究专项(04-01-03B)

摘　　要：为了寻求有效抑制污染土壤上水稻对重金属Pb、Cd的吸收、保持稻米卫生品质的技术方法,利用污染土壤盆栽试验和在污染区的田间试验,对施用石灰、碱性煤渣、高炉渣、水稻秸秆和猪厩肥等土壤改良剂降低水稻植株和糙米Pb、Cd含量的效应进行了比较研究。结果表明,在盆栽试验条件下,碱性煤渣的改良效果最为突出,基施5.0g·kg-1碱性煤渣,可使早稻糙米Pb和Cd含量分别降低78.6%和75.4%,晚稻糙米Pb和Cd含量分别降低45.7%和87.9%,使糙米Pb、Cd含量从严重超标水平降到了国家食品卫生标准允许的含量以下。石灰物质的改良效应主要取决于其对土壤pH的影响程度。在田间条件下,各种改良剂的效果均小于盆栽条件,不能将稻米Pb、Cd含量降低到国家食品卫生标准允许的含量水平。基于现有技术,从产品质量安全角度考虑,在重金属严重污染土壤上不宜种植水稻等粮食作物。For exploration of the measures and techniques in inhibiting the uptake of Pb and Cd by rice plants and protecting the hygienic quality of rice grains in the polluted soil environment, a comparative study was made on the effects of application of lime, alkaline coal cinder, blast furnace slag, rice straw and barnyard pig manure as soil amelioration materials on reducing the concentrations of Pb and Cd in plants and brown rice in polluted paddy soil through a pot and two field experiments. The alkaline coal cinder showed the best effect on soil amelioration in the pot experiment. A basal application of 5.0 g·kg^-1 of alkaline coal cinder resulted in a reduction of concentrations of Pb and Cd of brown rice by 78.6% and 75.4% in the early flee, and by 45.7% and 87.9% in the later flee, respectively. The concentrations of Pb and Cd in brown rice were therefore declined from a heavy pollution point to a level below the limit concentrations of Pb and Cd set by the national hygienic standard for unprocessed grains. Following the alkaline coal cinder, lime and blast furnace slag also gave an acceptable result. The effect of an alkaline material on reducing concentrations of Pb and Cd in the plant and brown rice was mainly depended on its capacity in increasing soil pH. In the field experiments, however, all of the tested materials showed a less and inconsistent effect compared with the pot experiment. No amelioration material was found to be effective enough to have the concentrations of Pb and Cd of the brown flee declined to a point below the limits of the national hygienic standard in the heavy polluted soils in our field experiments. Based on these results and considering the safety of hygienic quality of agricultural products, it is unsuitable to cultivate food crops, like paddy rice continuously in a soil polluted by heavy metals seriously.

关 键 词：土壤污染 Pb Cd 水稻 土壤改良剂 污染治理 稻米品质 

分 类 号：X53[环境科学与工程—环境工程]