模拟三峡库区消落带土壤有机磷酸酯淹水释放特征  

Simulation of the Migration and Release Characteristics of Organophosphate Esters in Fluctuation Zone Soil of the Three Gorges Reservoir During Flooding

作　　者：杨婷[1] 何明靖[1,2] 杨志豪 魏世强[1,2] YANG Ting;HE Ming-jing;YANG Zhi-hao;WEI Shi-qiang(College of Resources and Environment,Southwest University,Chongqing 400715,China;Chongqing Key Laboratory of Agricultural Resources and Environment,Chongqing 400716,China)

机构地区：[1]西南大学资源环境学院,重庆400715 [2]重庆市农业资源与环境研究重点实验室,重庆400716

出　　处：《环境科学》2018年第12期5487-5493,共7页Environmental Science

基　　金：国家自然科学基金项目(41403078;41771347)

摘　　要：本研究以三峡库区消落带典型土壤作为研究对象,通过室内模拟实验,探讨了有机磷酸酯(OPEs)的含量、环境温度、土壤有机质含量、微生物因素的变化对土壤中常见OPEs单体迁移释放的影响.结果表明,土壤中OPEs含量越低,其迁移释放量越低;有机质含量升高,土壤向上覆水释放的OPEs减少,预示土壤添加有机质后对OPEs的释放产生了一定的抑制作用,有机质对OPEs的吸附起主要作用,但当有机质含量(以干重计)高于30 g·kg^(-1)时,对OPEs释放的抑制作用并未显著增强;在环境温度为27℃时,三类OPEs的平均释放量为1 077. 3 ng·m L^(-1),高于7℃的释放量,说明高温对OPEs的释放起促进作用.微生物对其作用并不明显.氯类的OPEs包括磷酸三(2-氯乙基)酯(TCEP)、磷酸三(1-氯-2-丙基)酯(TCPP)和磷酸三(1,3-二氯异丙基)酯(TDCP)为最主要的释放单体,主要原因可能是氯类OPEs的辛醇水分配系数(Kow值)和有机碳分配系数(Koc值)比烷烃类和芳烃类OPEs低,更易溶于水体,不易被土壤中的有机质吸附,因此氯类OPEs更易从土壤中迁移释放到上覆水中,成为三峡库区上覆水中主要的OPEs单体.In this study, we investigated the effects of organophosphate ester （OPE） concentrations, temperature, soil organic matter, and microorganisms on the migration and release of several common OPEs from fluctuation zone soil in the Three Gorges Reservoir （TGR） to the overlying water by simulation experiments in the lab. The results indicate that the release of OPEs is determined based on their concentrations in the soil. The release of OPEs from soil to the overlying water decreases with increasing organic matter content, which indicates that the presence of organic matter could inhibit the migration of OPEs. However, the inhibition of the release of OPEs of organic matter is not significantly enhanced when the organic content （dry weight） is greater than 30 g·kg^-1. The average migration amount of OPEs is 1 077.3 Ng· mL^-1 at 27% , which was higher than that at 7℃, indicating that high temperature promotes the release of OPEs. The effect of microorganisms is not notable. Chlorine-based OPEs including Tris （2-chloroethyl） phosphate （TCEP）, Tris（1-chloro-2-propyl） phosphate （TCPP）, and Tris（ 1,3-Dichloro-2-Propyl） phosphate （TDCP） are the main monomers in the overlying water, mainly because both the Octanol-Water Partition Coefficient （Kaw） and Organic Carbon Partition Coefficient （Koc） of chlorine-based OPEs are lower than that of alkane-based OPEs and aromatic-based OPEs. Thus, chlorine-based OPEs are more easily dissolved in water and are not easily adsorbed by organic matter in the soil. Therefore, chlorine-based OPEs are more likely to migrate from the soil and to be released into the overlying water than other OPEs and become the main OPE monomers in the overlying water of the TGR.

关 键 词：三峡库区 消落带土壤 有机磷酸酯(OPEs) 淹水释放 

分 类 号：X131.2[环境科学与工程—环境科学] X524