Environmental dynamics of nitrogen and phosphorus release from river sediments of arid areas  

作　　者：SU Wenhao WU Chengcheng Sun Xuanxuan LEI Rongrong LEI Li WANG Ling ZHU Xinping 

机构地区：[1]College of Bioscience and Resources Environment,Beijing University of Agriculture,Beijing 102206,China [2]Xinjiang Tianxi Environmental Protection Technology Co.Ltd.,Urumqi 830000,China [3]College of Resources and Environment Sciences,Xinjiang Agricultural University,Urumqi 830052,China

出　　处：《Journal of Arid Land》2024年第5期685-698,共14页干旱区科学（英文版）

基　　金：the Xinjiang Science and Technology Support Project Plan(2022E02026);the Xinjiang Agricultural University Graduate Research and Innovation Programme(XJAUGRI2023049).

摘　　要：Human activities lead to the accumulation of a large amount of nitrogen and phosphorus in sediments in rivers.Simultaneously,nitrogen and phosphorus can be affected by environment and re-enter the upper water body,causing secondary pollution of the river water.In this study,laboratory simulation experiments were conducted initially to investigate the release of nitrogen and phosphorus from river sediments in Urumqi City and the surrounding areas in Xinjiang Uygur Autonomous Region of China and determine the factors that influence their release.The results of this study showed significant short-term differences in nitrogen and phosphorus release characteristics from sediments at different sampling points.The proposed secondary kinetics model(i.e.,pseudo-second-order kinetics model)better fitted the release process of sediment nitrogen and phosphorus.The release of nitrogen and phosphorus from sediments is a complex process driven by multiple factors,therefore,we tested the influence of three factors(pH,temperature,and disturbance intensity)on the release of nitrogen and phosphorus from sediments in this study.The most amount of nitrate nitrogen(NO_(3)^(–)-N)was released under neutral conditions,while the most significant release of ammonia nitrogen(NH_(4)^(+)-N)occurred under acidic and alkaline conditions.The release of nitrite nitrogen(NO_(2)^(-)-N)was less affected by pH.The dissolved total phosphorus(DTP)released significantly in the alkaline water environment,while the release of dissolved organic phosphorus(DOP)was more significant in acidic water.The release amount of soluble reactive phosphorus(SRP)increased with an increase in pH.The sediments released nitrogen and phosphorus at higher temperatures,particularly NH_(4)^(+)-N,NO_(3)^(–)-N,and SRP.The highest amount of DOP was released at 15.0℃.An increase in disturbance intensity exacerbated the release of nitrogen and phosphorus from sediments.NH_(4)^(+)-N,DTP,and SRP levels increased linearly with the intensity of disturbance,while NO_(3)^(–)-N an

关 键 词：SEDIMENT nitrogen and phosphorus environmental dynamics pseudo-second-order kinetics model dissolved organic phosphorus(DOP) Urumqi City 

分 类 号：X52[环境科学与工程—环境工程]