制革污泥堆存场地典型土壤剖面中污染物的垂向分布特征  

Vertical distribution characteristics of pollutants in a typical soil profile in the tannery sludge landfill site

作　　者：孔祥科[1,2] 黄国鑫 韩占涛 李志涛[3] 王平 许有明[1,2] 

机构地区：[1]中国地质科学院水文地质环境地质研究所,石家庄050061 [2]河北省地下水污染机理与修复重点实验室,石家庄050061 [3]环境保护部环境规划院,北京100012

出　　处：《南水北调与水利科技》2017年第6期96-100,共5页South-to-North Water Transfers and Water Science & Technology

基　　金：河北省自然科学基金项目(D2016504014);中国地质科学院水文地质环境地质研究所基本科研业务费项目(SK201613)~~

摘　　要：为了查明制革污泥对包气带土壤的污染状况,以某制革污泥堆存场地内典型土壤剖面为研究对象,研究污泥渗滤液中特征污染物在包气带土壤埋深0~200cm内的垂向分布特征,探讨不同形态氮及铬的分布规律,并采用高通量测序对土壤中的菌群组成进行了初步分析。结果表明:制革污泥成分复杂、浓度高,高浓度的含盐量(99 000mg/kg)、氮素(30 900mg/kg)及铬(30 970mg/kg)已对埋深20cm以上的浅层土壤造成严重污染,污泥中大量有机质及酸性物质导致浅层土壤pH降低和总有机碳(TOC)增大。随着土壤埋深增加,各污染物浓度呈明显下降趋势,但在埋深200cm处土壤中仍有一定浓度的有机氮(723mg/kg)及含盐量(7 070mg/kg)检出。研究区呈碱性的壤土对铬迁移具有明显的阻滞作用,当土壤埋深大于40cm,Cr(Ⅲ)浓度即下降至200mg/kg,Cr(Ⅵ)浓度下降至小于2mg/kg。高盐度、高铬污染对土壤中部分微生物生长具有抑制作用,变形杆菌门(Proteobacteria)、厚壁菌门(Firmicutes)及拟杆菌门(Bacteroidetes)成为受污染土壤中的优势种群。To find out the pollution status of tannery sludge to the soil in the unsaturated zone, we investigated the soil samples at the depth of 0～200 cm in a typical soil profile, and identified the vertical distribution characteristics of the main pollutants, especially the different forms of nitrogen and chromium. High-throughput sequencing was further applied to reveal the bacterial community structures of the mils. The results showed that the tannery sludge contained a variety of high-concentration contaminants, such as high salinity （99 000 mg/kg） ,total nitrogen （30 900 mg/kg） and total chromium （30 970 mg/kg） ,which had caused heavy contamination to the surface soil above 20 cm depth. The sludge leachate containing a large amount of organic matter and acid compounds caused a decrease in pH and an increase in TOC of the surface soil. The concentration of pollutants decreased obviously with the increase in soil depth. However,low-concentration organic nitrogen （723 mg/kg） and salinity （7 070 mg/kg） were still detected in the soil at the depth of 200 cm. The alkaline soil in the study area had a distinct retardation effect on the transfer of chromium. When the soil depth was deeper than 40 cm, the concentrations of Cr（ Ⅲ） and Cr（Ⅵ） decreased to less than 200 mg/kg and 2 mg/kg, respectively. High-salinity and high-chromium contamination can inhibit the growth of some microorganisms in the soil,and Proteobacteria, Firmicutes and Bacteroidetes will become the dominant microbial population in the contaminated soil.

关 键 词：制革污泥 土壤 氮 铬 垂向分布 

分 类 号：X508[环境科学与工程—环境工程]