河流潜流带生物扰动对重金属铜(Cu)迁移的影响研究  

Effect of bioturbation on the transporting of copper in the hyporheic zone

作　　者：赵晓田 宋进喜 程丹东[2,3] ZHAO Xiaotian;SONG Jinxi;CHENG Dandong(Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban andEnvironmental Sciences, Northwest University, Xi′an 710127, China;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China;University of Chinese Academy of Sciences, Beijing 100049, China)

机构地区：[1]西北大学城市与环境学院,陕西省地表系统与环境承载力重点实验室,陕西西安710127 [2]中国科学院水利部水土保持研究所,黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [3]中国科学院大学,北京100049

出　　处：《西北大学学报（自然科学版）》2019年第3期463-472,共10页Journal of Northwest University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(51379175,51679200);陕西省重点科技创新团队计划资助项目(2014KCT-27);陕西省水利科技计划资助项目(2018slkj-12)

摘　　要：生物扰动影响潜流带污染物的迁移并对水生生态系统造成威胁。以水丝蚓和摇蚊幼虫为扰动生物,利用21天室内微宇宙模拟实验确定两种生物及其不同密度扰动(0.5,1,1.5条/cm^2)以及组合扰动对上覆水和间隙水中铜(Cu)浓度和沉积物-水界面Cu扩散通量的影响。结果表明,水丝蚓的生物搬运和摇蚊幼虫的生物灌溉作用都促进上覆水和间隙水中Cu浓度显著提高。水丝蚓的生物搬运导致的向上输送促进了Cu由间隙水向上覆水中释放,而摇蚊幼虫的生物灌溉作用促进Cu由上覆水向间隙水迁移。混合组中摇蚊幼虫影响水丝蚓的向上搬运活动,减弱了Cu向上覆水的运动,有利于水体净化。生物密度对重金属Cu浓度和通量影响显著。水丝蚓扰动对重金属Cu的浓度和再分布的影响都与密度相关。间隙水中重金属浓度受水丝蚓和摇蚊幼虫的密度显著影响。研究结果可为潜流带重金属污染的防治提供参考。Bioturbation by macroinvertebrates can influence the transporting of heavy metals in the hyporheic zone.A 21-day simulated experiment was carried out to determine the effect of bioturbation by worm Limnodrilus hoffmeisteri and Chironomid larvae and with a density of 0.5,1 and 1.5 individual/cm^2each in single and combination on copper(Cu)transporting process.The overlying water and pore water were sampled and measured in each treatment at different times,and the Cu diffusive flux across the sediment-water interface was determined.The results revealed that both species with specific bioturbation modes increased the Cu concentration in overlying water and pore water.Bioturbation by worms promoted the Cu fluxes from pore water to overlying water due to the upward conveying activity,while the Cu fluxes from overlying water to pore water in the larvae and mixed treatments which might result from the bioirrigation activity of larvaes.The activity of larves potentially affected the worms and inhabited the upward process of worms.The worms showed a density-depend effect on the transporting of Cu.The Cu concentration in pore water was impacted by biological density.The results highlight the strong influence of bioturbation on metal transporting and provided reference to metal pollution controlof the hyporheic zone.

关 键 词：生物扰动 水丝蚓 摇蚊幼虫 铜(Cu) 潜流带 

分 类 号：X522[环境科学与工程—环境工程]