摘要
采用室内土柱淋洗试验方法,研究了污水灌溉条件下土壤碱度和石膏应用对土壤中重金属元素动态变化的影响。结果显示,Fe元素在土壤中累积,但它在碱性土壤中的累积程度大于在非碱性土壤或石膏应用后的碱性土壤中的累积程度。Mn和Zn元素在碱性土壤中累积而在非碱性土壤或石膏应用后的碱性土壤中淋溶。Cu元素在非碱性土壤中累积而在碱性土壤(不论石膏应用与否)中淋溶。Ni元素在所有土壤条件下均产生淋溶,但石膏的应用增大了Ni元素的淋溶程度。土壤碱度以及石膏在碱性土壤中的应用明显地改变了重金属元素的动态行为。某些重金属元素在土壤中的累积不会影响试验用污水的较长期灌溉使用。
Response of soil environment to wastewater irrigation affects sustainability of irrigation agriculture. Effects of soil sodicity and gypsum application on dynamical behavior of heavy metal elements under effluent irrigation were studied by means of soil column leaching method in laboratory. Three treatments were designed： nonsodic soil saturated with sodium adsorption ratio （SAR） 0, sodic soil saturated with SAR 30 and sodic soil saturated with SAR 30 ＋ gypsum application. Fe accumulated in all experimental soils, but its increased percentage in sodic soil was greater than that in nonsodic soil or gypsumapplied sodic soil. After leaching of 19～23 pore volumes, Fe contents increased to 0.93 and 0.563 mg·kg^-1 from initial content 0.43 mg·kg^-1, respectively, in sodic soils with and without application of gypsum. Application of gypsum obviously decreased accumulation of Fe in sodic soil. Manganese and Zn accumulated in sodic soil but eluviated in nonsodic soil and gypsum-applied sodic soil. After leaching of 19-23 pore volumes, Zn content in sodic soil increased to 0.160 mg·kg^-1 from initial content of 0.085 mg·kg^-1, which was much lower than 100 mg·kg^-1 of the First Class Criteria for National Soil Environmental Quality. Gypsum application in sodic soil changed dynamical behavior of Mn and Zn. Copper accumulated in nonsodic soil but eluviated in sodic soils no matter whether gypsum was applied or not, its content in nonsodic increased to 0.322 mg·kg^-1 at the end of experiment from initial content of 0.208 mg·kg^-1， which also was much lower than 35 mg·kg^-1 of the First Class Criteria. Nickel eluviated in all tested soil conditions, but gypsum application in sodic soil increased eluviation of Ni from the soil. Accumulations of some heavy metal elements in soils didn＇t affect irrigation application of studied wastewater for a long period.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2005年第4期751-756,共6页
Journal of Agro-Environment Science
基金
农业部农业生态环境科技项目
教育部留学回国人员基金和北京科技计划项目
关键词
污水灌溉
土壤碱度
钠吸附比
重金属元素
石膏
wastewater irrigation
soil sodicity
sodium adsorption ratio
heavy metal elements
gypsum
