摘要
环境选择在精细地理尺度河流浮游细菌多样性构建机制中的贡献已得到普遍认同.为回答浮游细菌集合群落中核心分类操作单元(Core Operational Taxonomic Units,Core OTUs)和特有分类操作单元(Unique Operational Taxonomic Units,Unique OTUs)是否具有相同的环境选择模式这一关键科学问题,本研究以高度人工化的北运河京津冀段为研究区域,尝试结合水质监测结果和高通量测序结果分别对核心OTUs局域群落和特有OTUs局域群落的空间变异进行环境解释.结果表明:北运河京津冀段水环境污染主要表现为再生水补给导致的无机氮和钙、镁盐分离子污染及再生水补给口物理扰动导致的有机污染两大类.浮游细菌集合群落中的核心OTUs局域群落结构的相似性明显高于特有OTUs局域群落结构,且二者空间变化规律及其环境驱动模式存在较大差异.核心OTUs局域群落空间分布规律与区域尺度地理空间分布模式具有较高一致性;与其空间变化相关程度最高的环境因子是TN、硝酸盐氮(NO_(3)^(-)-N)、K^(+)、Ca^(2+)、Na^(+)、Mg^(2+).氮和盐分离子随水流方向呈现显著下降趋势,与地理扩散距离表现出较强的协同变化规律.特有OTUs局域群落不具有显著的地理空间分布模式;与其空间分布有关的环境因子是温度(T)、氧化还原电位(ORP)和pH值;再生水补给口物理扰动对水文水质的间接影响.
The contribution of environmental selection to the construction mechanism of phytoplankton diversity in fine geographical scale rivers has been widely recognized.According to ecological theory of metacommunity,the determinant factors between the Core Operational Taxonomic Units(core OTUs)and the Unique Operational Taxonomic Units(unique OTUs)are potential to be different,as these two key components of microbial community in river ecosystems vary in dispersal ability and biological responses.To test this hypothesis,the Beijing-Tianjin-Hebei section of the Northern Canal River,which is highly artificial,was selected as the study area.To interpret the spatial variation of the core OTUs in local-community and the unique OTUs,the water quality monitoring results and high-throughput sequencing results were combined for comprehensive analysis.The results showed that inorganic nitrogen,cation such as Ca^(2+),Mg^(2+)induced by reclaimed water recharge and organic pollution caused by physical disturbance of reclaimed water recharge port were the key pollutants in the North Canal River.The intra-group similarity of the core OTUs in local-community was significantly higher than that of the unique OTUs,and the geographical distribution pattern and environmental divers differed a lot between these two key components.The spatial distribution law of core OTUs in local community was significantly consistent with geographic spatial distribution pattern,and environmental variables most closely related to spatial changes were TN,nitrate nitrogen(NO_(3)^(-)-N),K^(+),Ca^(2+),Na^(+)and Mg^(2+).Specifically,these critical environmental variables showed a significant decrease trend with the direction of water flow and showed a strong synergistic change with the geographical diffusion distance.While,unique OTUs in local-communities did not have a significant geographic spatial distribution pattern,and the crucial environmental variables determining the spatial distribution of the unique OTUs in local-communities were temperature,oxidation-reduction potential and pH,which were caused by the indirect effects of physical disturbance on hydrological quality of reclaimed water supply.
作者
靳燕
邱莹
董志
邸琰茗
赵栋梁
郭逍宇
JIN Yan;QIU Ying;DONG Zhi;DI Yan-ming;ZHAO Dong-liang;GUO Xiao-yu(College of Resources Environment and Tourism,Capital Normal University,Beijing 100048,China;School of Life Sciences,Peking University,Beijing 100871,China;Beijing North Canal Manage Office,Beijing 101100,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2021年第3期1378-1386,共9页
China Environmental Science
基金
北京市自然科学基金-北京市教委联合重点项目(KZ20190028042)联合资助。
