消落区沉积物落干期氮磷形态分析——以碧流河水库为例  

Morphology of nitrogen and phosphorus during sediment drying period in water level fluctuation zone:A case study of the Biliuhe Reservoir

作　　者：韩冬凝 许士国[1] 李维佳[1] 陈小强[1] HAN Dongning;XU Shiguo;LI Weijia;CHEN Xiaoqiang(School of Infrastructure Engineering,Dalian University of Technology,Dalian 116024,China;Liaoning Water Conservancy and Hydropower Survey and Design Research Institute Co.,Ltd.,Shenyang 110006,China)

机构地区：[1]大连理工大学建设工程学院,辽宁大连116024 [2]辽宁省水利水电勘测设计研究院有限责任公司,辽宁沈阳110006

出　　处：《水资源与水工程学报》2024年第5期11-19,共9页Journal of Water Resources and Water Engineering

基　　金：国家自然科学基金项目(42077348、42377412、51879031)。

摘　　要：水库水位变动致使消落区沉积物经历着频繁的干湿交替,为探讨落干过程对沉积物氮、磷的影响,以碧流河水库为例采集了消落区不同高程下的沉积物样品,并基于现场条件设计落干模拟试验,探讨持续落干条件下消落区沉积物氮、磷的多形态变化特征,为水库内源污染治理提供参考。研究发现:在沉积物干化过程中,受反硝化作用的影响,落干期TN的含量减少了2.99%,但随着水分蒸发反硝化作用易于发生的条件被破坏,TN的含量逐渐稳定;受矿化作用的影响存在有机磷(OP)向无机磷(IP)的形态转化,该转化提高了磷的生物有效性,且干化过程中会出现氮、磷向表层富集的现象。因此,持续的落干作用有利于沉积物中过量氮素的去除,有助于消落区植物生长和初级生产力的提升。Sediments in the water level fluctuation zone of the reservoir undergo frequent drying and flooding processes due to water level changes.In order to investigate the effect of drying process on nitrogen and phosphorus in the sediments,the study analyzed sediment samples collected at different elevations in the water level fluctuation zone of the Biliuhe Reservoir.Subsequently,a drying simulation experiment was carried out based on the field survey to explore the characteristics of nitrogen and phosphorus morphology change in the sediments of the water level fluctuation zone during the drying period,so as to provide a reference for the management of endogenous pollution in reservoirs.The results showed that TN content reduced by 2.99%under the influence of denitrification;however,as the conditions under which denitrification occurred were destroyed by water evaporation,the TN content gradually stabilized.Affected by mineralization,there was a morphological transformation of organic phosphorus(OP)to inorganic phosphorus(IP),which improved the bioavailability of phosphorus.Moreover,an enrichment of nitrogen and phosphorus to the surface layer was seen during the drying period.Therefore,sustained drying condition is conducive to the removal of excess nitrogen from the sediments,which in turn contributes to plant growth and primary productivity in the water level fluctuation zone.

关 键 词：水库 消落区 沉积物 持续落干 理化性质 

分 类 号：X524[环境科学与工程—环境工程]