人民长江2024，Vol.55Issue(2)：57-64,76,9.DOI:10.16232/j.cnki.1001-4179.2024.02.008
干湿交替对湖泊沉积物中磷的形态及释放速率影响
Effects of dry-wet alternations on form and release rate of phosphorus in lake sediments
摘要
Abstract
Sediment is an important endogenous source of phosphorus for the lake water environment.Due to climate change and human activities,the water level of Poyang Lake shows dramatic seasonal fluctuation.However,the effect of these seasonal dry-wet alternations on theendogenous releaseof phosphorus(P)from sediment remains unclear.In this paper,six silty loam sediment columns and six sand sediment columns were collected from the Fuhe River estuary into the Poyang Lake.Dry-wet alteration and long-term flooding scenarios were simulated respectively in the laboratory over a 45-day incubation to explore the effect of dry-wet alteration on sediment P form and endogenous release rate.The results showed that:①dry-wet alteration promoted the re-lease of P in sediments,with organic-P as the main form.The maximum P release rates of silty loam and sandy sediments under dry-wet alteration could reach up to 2.59 mg/(m2·d)and 1.97 mg/(m2·d)respectively,4～5 times higher than those in long-term flooding conditions.② Under dry-wet alteration,iron-aluminum bound P(Fe/Al-Pi)in sediment decreased,while weakly adsorbed P(WA-P),potentially active organic-P(PA-Po)and moderately active organic-P(MA-Po)in-creased.Calcium bound P(Ca-Pi)and non-active P(NA-Po)remained stable.③ During long-term flooding,Fe/Al-Pi increased,while MA-Po which can be mutually transformed with Fe/Al-Pi decreased.The easily released P(WA-P,PA-P)and inactive P(Ca-Pi,NA-Po)showed no significant changes.Those results suggest that dry-wet alteration promotes the transformation of Fe/Al-Pi to MA-Po,further converting into easily released P(WA-Pi and PA-Po),thereby facilitating en-dogenous P release in the sediment.关键词
沉积物/磷形态/内源释放/干湿交替/鄱阳湖Key words
phosphorus form/endogenous release/dry-wet alteration/sediment/Poyang Lake分类
资源环境引用本文复制引用
吴虎彬,李荣富,吴永明,姚忠,刘亚军,刘丽贞..干湿交替对湖泊沉积物中磷的形态及释放速率影响[J].人民长江,2024,55(2):57-64,76,9.基金项目
国家自然科学基金项目(42267029,42161022,42261020) （42267029,42161022,42261020）
江西省科学院省级科研项目经费包干制试点示范项目(2021YSBG22030,2023YSBG21005,2023YRCS001,2023YJC2005) （2021YSBG22030,2023YSBG21005,2023YRCS001,2023YJC2005）
长江生态环境保护修复联合研究二期项目(2022-LHYJ-02-0505-01) （2022-LHYJ-02-0505-01）
