磺胺嘧啶在原状土柱中的运移特征及模拟  

Characteristics and Simulation of Transport of Sulfadiazine in Undisturbed Soil Columns

作　　者：张步迪 林青 徐绍辉 ZHANG Budi;LIN Qing;XU Shaohui(College of Environmental Science ＆ Engineering,Qingdao University,Qingdao,Shandong 266071,China)

机构地区：[1]青岛大学环境科学与工程学院,山东青岛266071

出　　处：《土壤学报》2018年第4期879-888,共10页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(41571214);山东省自然科学基金青年项目(ZR2014DQ021)资助~~

摘　　要：以磺胺嘧啶(Sulfadiazine,SDZ)为研究对象,通过室内原状土柱(0~15 cm,土柱Ⅰ和15~30 cm,土柱Ⅱ)出流试验探讨了其在不同剖面深度处的迁移特征,运用Hydrus-1D软件对试验结果进行模拟,并对不同流速下磺胺嘧啶在0~200 cm土壤中的迁移行为做了预测。结果表明:SDZ在原状土柱Ⅱ中的穿透曲线相较于原状土柱Ⅰ的发生左移,即较深层土壤中,SDZ的迁移速度更快,这主要是受土壤理化性质,如有机质、阳离子交换量和p H等的影响;两区模型(TRM)模拟的R^2>0.91,均方根误差RMSE<0.061,不动水区域f<0.154,其模拟效果优于单点模型(OSM)和两点模型(TSM),表明土壤的不可动区域是吸附SDZ的重要部分。预测结果显示:同一流速时,SDZ浓度峰值随着土壤剖面深度增加而减小,出流时间逐渐增大;同一深度处,当水流速度从0.017 cm min^(-1)增加到0.030 cm min^(-1)再到0.100 cm min^(-1)时,磺胺嘧啶在土壤中的迁移速度不断加快,出流浓度也越来越高,当流速为0.100 cm min^(-1)时,SDZ可快速穿过土层进入地下水,其穿透曲线不再对称,出现拖尾现象。【Objective】Veterinary antibiotics are extensively used in livestock rearing industries all over the world for preventive and therapeutic treatments and growth promotion of poultry and/or animals.Antibiotics of the sulfonamide serial are commonly used in China,but once used,they are not so readily to be absorbed by the animals and are hence excreted along with feces and urine,which are often used as manure to build up soil fertility.After repeated application of the manure,sulfonamides therein tend to remain and accumulate in the soil and migrate from the soil into groundwater in certain environment.Longterm exposure to low concentrations of these antibiotics could be detrimental to non-target terrestrial and aquatic organisms.Therefore,investigation of the leaching behavior of these antibiotics in natural soils is the first logical step to assess their ecological risks and then develop corresponding pollution control strategies.【Method】In this research,focus was laid on one of the widely used sulfonamides：sulfadiazine（SDZ）,which is a compound slightly hydrophilic and low in adsorptivity in soils.Solute displacement experiments were performed to study migration processes of SDZ in undisturbed soil columns（Column I：0~15 cm,and column II：15~30 cm）.Breakthrough curves（BTCs）of SDZ and tracer bromide were measured and modeled using numerical models that took into account reversible and irreversible kinetic sorption sites,as well as dynamic and stagnant area with the aid of the Hydrus-1D software.After calibration the numerical model was then used to predict and simulate residing and migrating behaviors of the substance in 200 cm soil columns relative to leaching velocity.【Result】Results show that the BTCs in Soil ColumnⅡwere shifted to the left as compared with ColumnⅠ,which implied that,migration of SDZ was faster in the deeper soil layers.This is mainly due to changes in physical and chemical properties of the soil,such as humic acid content,cation exchange capacity and p H,with soil

关 键 词：磺胺嘧啶 原状土柱 HYDRUS-1D 迁移 

分 类 号：S152[农业科学—土壤学]