底泥营养释放对城市景观水质影响的模拟研究

孙凌等底泥营养释放对城市景观水质影响的模拟研究底泥营养释放对城市景观水质影响的模拟研究*孙凌。马微微刘欣萍孙依帆蒋丹王文静阚元卿。王慧(1．天津师范大学生命科学学院，天津市动植物抗性重点实验室，天津300387；2．清华大学环境学院，北京100084；3．天津市环境保护科学研究院，天津300191)摘要通过对天津市卫津河夏末底泥开展室内模拟，探讨重度富营养化河道底泥的氮、磷释放以及与上覆水浮游藻类种群变动的相互关联。结果表明：(1)以富营养湖水为上覆水较之蒸馏水能更快促进底泥氮、磷的释放。以湖水、蒸馏水为上覆水的处理组氨氮极大值分别为4．36、3．61mg／L；溶解性正磷酸盐极大值分别为110．3、81．9btg／L。(2)湖水样品室内培养后，优势蓝、绿藻门的细胞密度与生物量都成倍增长。添加底泥开展培养，蓝藻门和硅藻门快速增殖，绿藻门的生长因溶解性正磷酸盐的竞争与消耗而受到抑制。底泥营养释放导致上覆水层富营养化程度加剧，硅藻门的梅尼小环藻(Cyclotellameneghiniana)被大量检出且增殖迅速。(3)上覆水为蒸馏水时，氮、磷营养自底泥的持续释放，促使绿藻门的土生绿球藻(Chlorococcumhumicola)成为绝对优势种，藻类总生物量最高。关键词底泥城市景观水体富营养化浮游藻类营养释放DOI：10．15985／j．cnki．1001-3865．2O15．07．O07SimulationsoftheeffectsofsedimentnutrientreleaseonurbanlandscapewaterqualitySUNLing，MAWeiwei，L儿，Xinping，SUNVif~n，JIANGDan，WANGWenjing，KANYuanqing。，WANGHui．(1．TianjinKeyLa—boratoryofAnimalandPlantResistance，CollegeofLifeSciences，TianjinNormalUniversity，Tianjin300387；2．SchoolofEnvironment，TsinghuaUniversity，Beijing100084；3．TianjinAcademyofEnvironmentalSciences，Tianjin300191)Abstract：Thestudyaimedtofindthecorrelationsbetweenthesedimentnutrientreleasesandthevariationsofphyt0planktoncommunityinahypertrophicriver．IndoorsimulationswerecarriedoutwiththesedimentcollectedfromtheWeijinRiver，Tianiininlatesummer．Theresultsshowedthat：(1)Itacceleratedthenitrogenandphosphor～usreleasefromthesedimentwhencoveredbythenaturaleutrophiclakewatercomparedtothedistilledwater．Duringtheexperiments，themaximumconcentrationsofammonianitrogenwere4．36mg／Linthesediment-lakewatergroup(GroupB)and3．61mg／Linthesediment-distilledwatergroup(GroupC)．Themaximumconcentrationsofsolubleorthophosphatewere110．3，81．9／~g／Linthetwogroupsrespectively．(2)Duringtheindoorculture，boththecellabundanceandbiomassofthedominantcyanobacteriaandehlorophytesinthelakewater(GroupA)almostdoubled．Addingthesedimenttothelakewater，thecyanobacteriaanddiatomsrapidlybecamethedominantphyla．Thegrowthofchlorophyteswasgreatlyrestrainedbecauseofthedepletionofsolubleorth0phosphateinthecompetition．Thenu—trientsfromthesedimentcausedmoreseriouseutrophication