三峡库区笋溪河沉积物污染及其氮磷营养盐释放特征  

Characteristics of sediment pollution and nitrogen and phosphorus release in the sediment-overlying water interface in the Sunxi River in the Three Gorges Reservoir Area

作　　者：宁一泓 王海燕[1] 侯文宁 赵晗 邹佳何 NING Yihong;WANG Haiyan;HOU Wenning;ZHAO Han;ZOU Jiahe(State Key Laboratory of Efffcient Production of Forest Resources,Key Laboratory of Forest Cultivation and Protection of Ministry of Education,College of Forestry,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]林木资源高效生产全国重点实验室/森林培育与保护教育部重点实验室/北京林业大学林学院,北京100083

出　　处：《应用与环境生物学报》2025年第2期208-220,共13页Chinese Journal of Applied and Environmental Biology

基　　金：国家“十三五”重点研发计划项目“三峡库区面源污染景观生态防治技术集成与示范”(2017YFC0505306)资助。

摘　　要：为探明三峡库区沉积物污染特征和沉积物与上覆水界面氮磷释放规律,以库尾笋溪河沉积物为研究对象,对其污染现状进行分析和评价,并通过室内模拟试验,考察上覆水环境因子(扰动、pH、温度)对笋溪河沉积物氮磷释放的影响.结果表明:(1)沉积物总氮(STN)和总磷含量均值分别为430和200 mg/kg,有机质(SOM)含量的最小值、最大值和平均值分别为0.73、46.31、10.04 g/kg;STN含量与SOM呈极显著正相关(P <0.01).(2)单因子指数评价表明,河道中个别样点沉积物氮的污染指数已达到重度污染水平,沉积物磷的污染指数在0.18-0.80之间,属于清洁—轻度污染等级;整体而言,存在污染的样点占总样点数的26.5%.(3)室内模拟试验发现:上覆水总氮浓度在温度为35℃时显著高于5℃和25℃(P <0.05);上覆水总磷浓度在100 r/min的扰动水平下显著低于200 r/min(P <0.05);而硝态氮在酸性(pH=5)和碱性(pH=9)环境中的释放量则显著高于中性(pH=7)环境.总之,上覆水环境因子显著影响了沉积物氮磷释放,沉积物氮磷营养盐释放潜力为评估上覆水体的释放风险提供了重要信息;以上研究结果可为笋溪河水体富营养化防治提供参考.(图5表7参42)Water is a vital resource for life that plays a crucial role in ecosystems and natural landscapes.When water is polluted,large quantities of pollutants discharged accumulate in the sediment over the years.The sediment then becomes a potential source of pollution for the overlying water after external pollution sources have been effectively controlled.This study aimed to explore the characteristics of sediment pollution in the Three Gorges Reservoir Area and the law of nitrogen and phosphorus release at the sediment-overlying water interface.Surface sediments were collected at a depth of approximately 10 cm from the Sunxi River in the tail area of the Three Gorges Reservoir to analyze and evaluate the status of sediment pollution.The sediments of the Sunxi River were considered as the research object and the effects of environmental factors(disturbance,pH,and temperature)on the release of nitrogen and phosphorus from the sediments of the Sunxi River were investigated through indoor simulation experiments.The results showed that:(1)The mean sediment total nitrogen(STN)and total phosphorus(STP)were 430 mg/kg and 200 mg/kg,respectively.The minimum,maximum,and mean sediment organic matter(SOM)contents were 0.73,46.31,and 10.04 g/kg,respectively.Significant positive correlation was observed between STN and SOM(P<0.01).(2)The single factor index evaluation showed that the nitrogen pollution index of the sediments at several sampling points reached a severe pollution degree and the phosphorus pollution index ranged from 0.18 to 0.80,indicative of clean to mild pollution.Overall,contaminated samples accounted for 26.5%of all the sampling points.(3)Indoor simulation experiments showed that the water total nitrogen concentration at 35℃was signiffcantly higher than that at 5℃and 25℃(P<0.05).The water total phosphorus concentration was signiffcantly lower at 100 r/min than 200 r/min(P<0.05)and the release of nitrate nitrogen in the acidic(pH=5)and alkaline(pH=9)environments was signiffcantly higher than that in the neut

关 键 词：笋溪河 沉积物 污染指数 氮磷释放 水体富营养化 

分 类 号：X524[环境科学与工程—环境工程]