太湖西北部典型疏浚-对照湖区内源性营养盐释放潜力对比

J．LakeSci．(湖泊科学)，2014，26(6):829-836http://www．jlakes．org．E-mail:jlakes@niglas．ac．cn2014byJournalofLakeSciences太湖西北部典型疏浚/对照湖区内源性营养盐释放潜力对比*陈超1，2，钟继承1＊＊，邵世光3，刘成1，2，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:通过采集太湖西北部闾江口、八房港、月亮湾和竺山湾疏浚区与未疏浚对照区8个样点共32根沉积物柱状样于室内进行内源负荷模拟研究和沉积物基本性质分析发现，除闾江口疏浚区沉积物总磷和可交换态磷含量高于未疏浚区外，其余指标如烧失量、总氮、可交换态氮等均表现为未疏浚区沉积物高于疏浚区沉积物的特征，说明疏浚区沉积物营养盐的释放潜力低于未疏浚对照组．八房港、月亮湾以及竺山湾疏浚区沉积物铵态氮、正磷酸盐的潜在释放速率均比相应未疏浚对照区沉积物低，疏浚区沉积物铵态氮的潜在释放速率分别是未疏浚区的65．3%、88．8%和21．9%，正磷酸盐的潜在释放速率分别是未疏浚区的－26．6%、11．3%和50．2%．而闾江口疏浚区沉积物铵态氮和正磷酸盐的潜在释放速率却远高于未疏浚区(疏浚区分别为未疏浚区的2．6倍和6．4倍)，这可能与闾江口水体呈现弱还原环境及沉积物中有机质含量高有关，另外也可能与闾江口沉积物污染物的赋存深度和疏浚工程的疏浚深度有关．关键词:底泥疏浚;潜在释放速率;效果评估;太湖Onthepotentialreleaseratesofnutrientfrominternalsources:Acomparativestudyoftypicaldredgedandun-dredgedareas，northwesternLakeTaihuCHENChao1，2，ZHONGJicheng1，SHAOShiguang3，LIUCheng1，2＆FANChengxin1(1:StateKeyLaboratoryofLakeScienceandEnvironment，NanjingInstituteofGeographyandLimnology，ChineseAcademyofSciences，Nanjing210008，P．Ｒ．China)(2:UniversityofChineseAcademyofSciences，Beijing100049，P．Ｒ．China)(3:CollegeofHydrologyandWaterＲesources，HohaiUniversity，Nanjing210098，P．Ｒ．China)Abstract:Simulatedresearchofinternalloadingreleasewascarriedouttoassesstheeffectsofsedimentdredgingoninternalsourcerelease，andthebasicpropertiesofdredgedandun-dredgedsedimentswasalsoanalyzedinthisstudy．Intactsedimentcoreswerecollectedfromdredgedandun-dredgedsitesinfourareasincludingBafangPort，LvjiangPort，MoonBayandZhushanBay，north-westernLakeTaihu．Theresultsshowedthatthepotentialreleaseratesofsedimentscanbeefficientlypreventedbydredgingbe-causeoftheinternalloadingssuchasthelossonignition，totalnitrogenandammoniumnitrogenwhichweresignificantlylowerafterdredging．ThepotentialreleaseratesofammoniumindredgedsitesofBafangPort，MoonBayandZhushanBaywas65．3%，88．8%and21．9%，respectively．ThepotentialreleaseratesofphosphorusindredgedsitesofBafangPortevenshowednegative(－0．35mg/(m2·d))whichmeansthediffusiondirectionofphosphoruswasfromoverly