水丝蚓蚓粪对沉积物微环境及氮磷吸附特性的影响  

EFFECTS OF TUBIFICID WORMS EXCRETION-FECAL PELLETS ON SEDIMENT MICROENVIRONMENT AND ADSORPTION CHARACTERISTICS OF NITROGEN AND PHOSPHORUS

作　　者：孙培荣 李大鹏[1] 徐楚天 陈姝彤 汤尧禹 SUN Peirong;LI Dapeng;XU Chutian;CHEN Shutong;TANG Yaoyu(School of Environmental Science and Engineering,Suzhou University of Science and Technology,Suzhou 215009,China)

机构地区：[1]苏州科技大学环境科学与工程学院,江苏苏州215009

出　　处：《环境工程》2023年第8期8-17,共10页Environmental Engineering

基　　金：国家自然科学基金项目(51778393)。

摘　　要：以太湖沉积物和上覆水构建室内模拟实验,探究水丝蚓蚓粪对沉积物微环境、表层沉积物氮、磷吸附特性和微生物菌群分布的影响。结果表明:蚓粪显著影响了表层沉积物的含水率、孔隙度、烧失重和微生物活性。沉积物表层DO浓度和氧化还原电位的降低,以及沉积物深处氧化还原电位的升高与水丝蚓引起颗粒垂向迁移有关。等温吸附实验中,新生蚓粪氨氮平衡浓度(EC_(0))和磷平衡浓度(EPC_(0))值分别为0.73,0.014 mg/L,对氮、磷表现出了良好的固定能力。水丝蚓组蚓粪与对照组沉积物微生物种群结构相似,但微生物多样性有所降低。蚓粪中放线菌门、绿弯菌门、蓝藻细菌门相对丰度的增加,表明蚓粪堆积对沉积物有机质的分解和氮磷物质的释放具有促进作用,蚓粪中Cyanobium_PCC-6307菌属的相对丰度为对照组的3倍,表明蚓粪堆积与水华存在一定的关联性。To investigate the effect of fecal pellets on the sediment microenvironment,nitrogen and phosphorus adsorption characteristics of surface sediment,and microbial community distribution,a laboratory simulation experiment was constructed by using the sediment and the overlying water from Taihu Lake.The results indicated that fecal pellets significantly changed the water content,porosity,loss on ignition and microbial activity of surface sediment.The decrease of dissolved oxygen concentration and redox potential in surface sediment and the increase of redox potential in deep sediment was related to the vertical migration of particles caused by tubificid worms.In the isothermal adsorption experiment,the newborn fecal pellets showed a good fixation capacity for nitrogen and phosphorus(EC_(0)=0.73 mg/L,EPC_(0)=0.014 mg/L).The microbial community structure of fecal pellets in the tubificid worm group was similar to that in the control group,but the microbial diversity decreased in the former group.The increase in the relative abundance of Actinobacteria,Chloroflexi and Cyanobacteria in fecal pellets suggested that fecal pellets accumulation could promote the decomposition of organic matter and the release of nitrogen and phosphorus in sediments.The relative abundance of Cyanobium_PCC-6307 in fecal pellets was three times higher than in the control,implying a correlation between fecal pellets accumulation and water bloom.

关 键 词：水丝蚓 生物扰动 氮磷吸附 微环境 蚓粪 

分 类 号：X52[环境科学与工程—环境工程]