太湖草源性-湖泛-水域沉积物营养盐释放估算

J．LakeSci．(湖泊科学)，2014，26(2):177-184http://www．jlakes．org．E-mail:jlakes@niglas．ac．cn2014byJournalofLakeSciences太湖草源性“湖泛”水域沉积物营养盐释放估算*申秋实1，周麒麟1，2，邵世光3，刘成1，2，张雷1，范成新1＊＊(1:中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室，南京210008)(2:中国科学院大学，北京100049)(3:河海大学水文水资源学院，南京210098)摘要:于太湖草源性“湖泛”暴发期，采集柱状沉积物并应用peeper被动采样装置获得“湖泛”区原位沉积物间隙水．泥水样品分析表明:“湖泛”发生水域表层(0～7cm)沉积物的含水率、孔隙度和有机质含量均明显高于对照区，其中有机质含量更是对照区样品的4倍左右，沉水植物残体促使表层沉积物物化性质改变的作用明显;“湖泛”发生水域表层沉积物间隙水中铵态氮(NH+4-N)、溶解性反应磷(SＲP)及Fe2+含量远高于未发生区，植物残体降解对沉积物厌氧环境的营造显著．运用分子扩散模型对沉积物释放通量估算:“湖泛”发生区沉积物NH+4-N、SＲP和Fe2+的释放速率分别是对照区的49．8、15．3和123．1倍．研究认为，草源性“湖泛”水体氮、磷等营养物含量升高的主要原因是沉积物的释放，而“湖泛”所营造的厌氧环境是氮、磷释放急剧增加的主要驱动因素．关键词:湖泛;氮;磷;沉积物释放;peeper;太湖Estimationofin-situsedimentnutrientsreleaseatthesubmergedplantinducedblackbloomareainLakeTaihuSHENQiushi1，ZHOUQilin1，2，SHAOShiguang3，LIUCheng1，2，ZHANGLei1＆FANChengxin1(1:StateKeyLaboratoryofLakeScienceandEnvironment，NanjingInstituteofGeographyandLimnology，ChineseAcademyofSciences，Nanjing210008，P．Ｒ．China)(2:UniversityofChineseAcademyofSciences，Beijing100049，P．Ｒ．China)(3:CollegeofHydrologyandWaterＲesource，HohaiUniversity，Nanjing210098，P．Ｒ．China)Abstract:DuringthesubmergedplantinducedblackbloomperiodinLakeTaihu，sedimentcoreswerecollectedandporewaterswereacquiredusingpeeperin-situpassiveporewatersamplersattheblackbloomandthecontrolareas．Thesedimentsanalysisre-sultsshowedthatthewatercontent，porosityandorganicmatter(LOI)wereobviouslyhigherinthesurfacesediment(0-7cm)intheblackbloomareathanthoseinthecontrolarea，amongwhichtheLOIcontentswereabout4timeshigher．Thephysicalandchemicalcharacteristicsofsurfacesedimentswereinfluencedbythesubmergedplantresiduesgreatly．Ammonium(NH+4-N)，sol-ublereactivephosphorus(SＲP)andFe2+contentsinsurfaceporewatersattheblackbloomareaweresignificantlyhigherthanthoseatthecontrolarea．ThesedimentreleasefluxesofNH+4-N，SＲP，andFe2+werealsoestimatedbyusingtheporewaterdif-fusionmodelapproach．Comparedtothecontrolarea，thereleasefluxesofNH+4-N，SＲP，andFe2+intheblackbloomareawere49．8，15．3，and123．1timeshigher，respectively．Theresear