木兰溪感潮河段沉积物耗氧速率及其相关影响因素研究  

Sediment Oxygen Demand and Related Influencing Factors in Mulan River Tidal Reach

作　　者：周佳男 方梦园 雷啟焘 侯国庆 赵天慧[2] 张思远 赵晓丽[2] 汤智[2] ZHOU Jianan;FANG Mengyuan;LEI Qitao;HOU Guoqing;ZHAO Tianhui;ZHANG Siyuan;ZHAO Xiaoli;TANG Zhi(School of Energy and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China;State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China)

机构地区：[1]北京科技大学能源与环境工程学院,北京100083 [2]中国环境科学研究院,环境基准与风险评估国家重点实验室,北京100012

出　　处：《环境科学研究》2023年第8期1518-1531,共14页Research of Environmental Sciences

基　　金：国家自然科学基金项目(No.42077349);国家重点研发计划项目(No.2022YFF1303304)。

摘　　要：溶解氧(DO)是衡量水环境质量、水生态健康的主要指标,感潮河段DO浓度偏低是河口区域水生态环境质量显著改善亟待解决的问题.本研究以木兰溪感潮河段为研究对象,系统研究了不同温度条件下,不同区域沉积物耗氧速率(SOD)的变化,分析了不同区域沉积物中总有机碳(TOC)、总氮(TN)、Fe、Mn、氨氮(NH_(4)^(+)-N)、S等耗氧物质的含量分布以及对沉积物SOD的影响,阐明了耗氧物质对沉积物SOD的影响机制.结果表明:(1)木兰溪感潮河段春秋季的SOD为3.06~16.64 mg/(m^(2)·h),夏季的SOD为14.02~52.44 mg/(m^(2)·h),温度对SOD有很大影响,夏季沉积物耗氧严重.(2)上游河流受化学耗氧影响较大,低温季节SOD大于海口区域,而海口受生物耗氧影响较大,高温季节SOD明显大于上游河流区域;左、右岸的SOD大于河道中间,夏季养殖区的SOD大于木兰溪河道.(3)相关性分析显示,SOD与沉积物中的TOC、TN和Fe含量均没有显著的相关关系,春秋季的SOD与沉积物中的Mn含量具有显著的正相关关系,夏季的SOD与沉积物中的NH_(4)^(+)-N和S含量均具有极显著的正相关关系,且夏季DO浓度与SOD具有显著的负相关关系.研究显示,木兰溪感潮河段沉积物SOD时空差异性明显,夏季沉积物SOD显著升高,对上覆水DO浓度偏低具有潜在风险.Dissolved oxygen(DO)is a key indicator for water environmental quality and water ecological health.Low level of DO poses a serious problem for improving water ecological environment quality in tidal reach.In this study,the tidal reach of the Mulan River was selected as the research area.The sediment oxygen demand(SOD)in different regions was studied under different temperature conditions.The distribution of oxygen consuming substances such as total organic carbon(TOC),total nitrogen(TN),Fe,Mn,ammonia nitrogen(NH_(4)^(+)-N)and sulfur(S)in the sediments of different regions were analyzed,which clarified the influence of oxygen consumption substances on SOD level in sediments.The results showed that:(1)The SOD in the tidal reach of Mulan River was 3.06-16.64 mg/(m^(2)·h)in spring and autumn,and 14.02-52.44 mg/(m^(2)·h)in summer.The significant influence of temperature on the SOD was confirmed in this study.In addition,the results of summer revealed the grim situation of oxygen consumption in sediment.(2)The upstream river was affected by chemical oxygen depletion with high SOD in the low temperature season,while the estuary was affected by biological oxygen depletion with significantly high SOD in the high temperature season than upstream river areas.The SOD in the left and right banks of the Mulan River was higher than that in the middle.Moreover,the SOD in the mudflat aquaculture area was higher in summer.(3)The correlation analysis showed that the SOD had no significant correlation with TOC,TN or Fe in the sediments,the SOD in spring and autumn had significant positive correlation with Mn,and the SOD in summer had extremely significant positive correlation with NH_(4)^(+)-N and S in the sediments.Besides,there was a significant negative correlation between DO concentration and SOD in summer.This study indicated that the temporal and spatial variability of SOD in the tide reach of Mulan River was obvious,and the sediment oxygen consumption rate was significantly higher in summer,which had a potential risk for lo

关 键 词：木兰溪 感潮河段 溶解氧(DO) 沉积物耗氧速率(SOD) 相关性 

分 类 号：X703[环境科学与工程—环境工程]