摘要
为了解滤食性鱼类粪便对湖泊沉积物N_(2)O排放的影响,收集千岛湖沉积物、水与鲢(Hypophthalmichthys molitrix)粪便,按照不同的配比设置3个实验组,开展为期90d的模拟封闭培养转化实验。通过分析N_(2)O的通量特征、水和沉积物混合物的理化指标、氮代谢酶活性与微生物序列,确定影响氮转化的主要环境因素及关键微生物类群。结果表明,在鱼粪的影响下,水-气界面的N_(2)O排放通量在45d达到最高,随后迅速下降,于45—60d由排放转化为吸收,沉积物中鱼粪的添加比例越大,培养后期对N_(2)O的吸收量越多。鱼粪的添加会显著提高循环系统中可溶性碳与氨氮的浓度,同时降低水体中的DO,显著提高沉积物中4种相关氮转化酶的活性。沉积物的16S rRNA分析表明,添加鱼粪会显著提高沉积物中变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidota)的相对丰度,其中芽孢杆菌属(Bacillus)丰度的提高可能是使沉积物表现出更强的N_(2)O吸收效率的主要原因,为湖泊滤食性鱼类增殖的N_(2)O减排机制提供了理论参考。
Filter-feeding fish play an important role in coping with the eutrophication process of water bodies.In order to understand the effect of filter-feeding fish faeces on N_(2)O emissions from lake sediments,we collected sediments,water,and feces of Hypophthalmichthys molitrix in Qiandao Lake,and set up three experimental groups according to different ratios.A 90-day simulated closed culture transformation experiment was carried out.The key microbial strains affecting nitrogen transformation and the main environmental factors influencing nitrogen transformation were identified by analysing the emission flux characteristics of N_(2)O,the physicochemical indexes of water and sediment mixtures,nitrogen metabolism enzyme activities,and microbial sequences.The results showed that under the influence of fish faeces,the N_(2)O emission flux at the water-gas interface reached the highest on day 45 and then decreased rapidly.From day 45 to day 60,the flux shifted from emission to uptake.The greater the proportion of fish faeces added to the sediment,the greater the uptake of N_(2)O during the later stages of incubation.The addition of fish faeces significantly increased the concentration of soluble carbon and ammoniacal nitrogen in the recirculation system,while decreasing DO in the water column.It also significantly enhanced the activities of four relevant nitrogen-converting enzymes in the sediments.16sRNA analysis of the sediments showed that the addition of fish manure significantly increased the relative abundance of Proteobacteria,Firmicutes,and Bacteroidota.The increased abundance of Bacillus probably being the main reason for the sediments to show stronger N_(2)O uptake efficiency.This study provides a theoretical reference for the N_(2)O abatement mechanism of filter-feeding fish proliferation in lakes.
作者
陈宏远
车轩
盘家永
李一鸣
王婕
朱林
孟展鹏
卢小利
崔帅康
刘慧仪
CHEN Hong-Yuan;CHE Xuan;Pan Jia-Yong;LI Yi-Ming;WANG Jie;ZHU Lin;MENG Zhan-Peng;Lu Xiao-Li;Cui Shuai-Kang;LIU Hui-Yi(College of Fisheries and Life Science,Shanghai Ocean University,Shanghai 201306,China;Fishery Machinery and Instrument Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200092,China;Hangzhou Qiandao Lake Development Group,Hangzhou 311700,China)
出处
《水生生物学报》
北大核心
2025年第7期156-166,共11页
Acta Hydrobiologica Sinica
基金
国家重点研发计划(2023YFD2400905)
中国水产科学研究院中央级公益性科研院所基本科研业务费专项资金CAFS(2023TD67)资助。
关键词
滤食性鱼类
千岛湖沉积物
N_(2)O排放通量
氮循环
微生物机制
鲢
Filter-feeding fish
Lake sediments
N_(2)O emission flux
Nitrogen cycle
Microbiological mechanism
Hypophthalmichthys molitrix
作者简介
陈宏远(1997-),男,硕士研究生,研究方向为渔业生态学。E-mail:17889985377@163.com;通信作者:车轩(1981-),男,研究方向为水域生态工程。E-mail:chexuan@fmiri.ac.cn。
