蓝藻暴发对巢湖表层沉积物氮磷及形态分布的影响

中国环境科学2014，34(5)：1285-1292ChinaEnvironmentaIScience蓝藻暴发对巢湖表层沉积物氮磷及形态分布的影响孔明，一，张路，尹洪斌，蔡永久，高俊峰(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，江苏，南京210008；2．中国科学院大学，北京100049)摘要：以巢湖表层沉积物及上覆水体为对象，于蓝藻暴发前(4月)和蓝藻暴发期(7月)采集水样及沉积物样品，分析了氮磷及其形态赋存特征，并探讨了沉积物氮磷及其形态与蓝藻暴发的关系．结果发现，蓝藻暴发时，巢湖表层沉积物总磷减少，总氮增加，同时削弱了磷在空间上分布的异质性．从氮磷形态来看，蓝藻暴发未造成巢湖表层沉积物氮形态(NH4。。N、NO3一N和Org—N)含量和比例的明显波动，但却造成了活性磷(弱吸附态磷和铁铝结合态磷之和)含量及比例的下降，钙结合态磷(Ca-P)以及有机磷(OP)含量及比例增加，生物有效性磷(AAP)的含量的减小．相关性分析表明，上覆水中叶绿素a(Chl—a)的浓度与铁铝结合态磷(Fe／AI—P)以及有机磷(OP)的含量显著相关(尸<0．05)，却与氮形态(铵态氮，硝态氮和有机氮)相关性不显著．巢湖沉积物磷(Fe／AI—P及AAP)对巢湖水体蓝藻暴发具有促进作用，而氮及其形态对蓝藻暴发作用较弱．关键词：蓝藻暴发：沉积物；氮磷；形态：生物有效性中图分类号：X524文献标识码：A文章编号：1000—6923(2014)05—1285—08InfluenceofalgaebloomondistributionoftotalandspeciationofnitrogenandphosphorusinthesurfacesedimentsfromLakeChaohu．KONGMing，ZHANGLu，YINHong—bin，CAIYong-jiu，GAOJun—feng(1．StateKeyLaboratoryofLakeScienceandEnvironment，NanjingInstituteofGeographyandLimnology,ChineseAcademyofSciences，Nanjing210008，China：2．UniversityofChineseAcademyofSciences，Beijing100049，China)．ChinaEnvironmentalScience，2014，34(5)：1285M292Abstract：SurfacesedimentandoverlyingwaterfromLakeChaohuweresampledbefore(inApril)andafter(inJuly)algalbloom．Totalandspeciationofnitrogenandphosphorusinthesedimentswereanalyzed，andtheirrelationshipwithalgalbloomwasdiscussed．Algalbloomcouldincreasetheconcentrationsofnitrogenanddecreasetheconcentrationsofphosphorusfromsurfacesediments，andthereforeweakentheheterogenicityofsedimentphosphorusconcentrations．Thealgalbloomdidnotcausetheobviousfluctuationofconcentrationsandproportionofnitrogenspeciation(NH4N，NO3一N，Org-N)，butdecreasetheconcentrationsandproportionofreactivephosphorus(LPandFe／A1一P)ratherthantheproportionandcontentofCa—boundP(Ca-P)insurfacesediments．Meanwhile，algalboomdecreasetheconcentrationsofsurfacesedimentbioavailablephosphorusfAAP)inwholelake．CorrelationanalysisindicatedthattheconcentrationofChlorophyll-acorrelatedsignificantlywithFe／A1一boundP(Fe／A1·P)andorganicphosphorus(OP)(尸<0．05)butwiththenitrogenforms(NHaN，NO3_N，Org—N)insurfacesedim