西部人居环境学刊2025，Vol.40Issue(5)：32-37,6.DOI:10.13791/j.cnki.hsfwest.20250929002
河流基质附着生物膜与河流水质的相关关系及驱动路径
Correlation and driving pathways between substrate attached biofilms and water quality in rivers:A case study of Panxi River in Chongqing
摘要
Abstract
Eutrophication has become a prominent environmental challenge endangering the ecological health of urban rivers.In Chongqing's Panxi River,a typical urban watercourse affected by anthropogenic nutrient inputs,excessive nitrogen(N)and phosphorus(P)loads have disrupted aquatic nutrient cycling,impairing the river's natural ecological balance and highlighting the urgent need to clarify the regulatory role of substrate-attached biofilms in water quality evolution.As key components of river ecosystems,biofilms on natural substrates(e.g.,cobbles and gravels)play a vital role in mediating N and P biogeochemical cycles;however,their specific regulatory pathways for N and P transformation and intrinsic coupling relationship with spatiotemporal water quality changes remain to be fully elucidated.To address this knowledge gap,this study systematically analyzed the water quality and characteristics of substrate-attached biofilms at 9 sampling sites along the Panxi River,aiming to explore the aforementioned scientific questions.The 9 sampling sites were strategically selected to cover the upstream,midstream,and downstream sections of the Panxi River,ensuring the capture of full gradients of environmental conditions and pollution levels.At each site,key water quality indicators related to eutrophication were measured,including total nitrogen(TN),total phosphorus(TP),dissolved oxygen(DO),pH,and dissolved organic carbon(DOC).Meanwhile,substrate-attached biofilms were collected from the surfaces of natural substrates;their core characteristics,such as microbial community structure,biomass,algal content(quantified by chlorophyll a),and abundance of functional bacteria,were analyzed to reveal their response to water quality changes.The upstream biofilm microbial community was structurally simple,with low biomass dominated by degradative bacteria,while the downstream was characterized by an increase in photosynthetic and nitrogen-fixing functional bacteria.Biofilm algae(chlorophyll a reaching 86.33 μg/L)and functional bacteria(such as Pseudanabaena and Nitrospira)became more abundant,indicating spatial synchronicity between biofilm community structure and water quality changes.Furthermore,a complex correlation exists between them:the accumulation of nutrients in the water(especially TP>0.5 mg/L,TN>6 mg/L)provides a material basis for biofilm development,while mature biofilms reshape the physicochemical characteristics of the water by altering microenvironments(e.g.,DO,pH),enhancing soluble phosphate retention,and promoting DOC metabolism.In conclusion,this study clarifies the spatial coupling pattern between substrate-attached biofilm communities and water quality in the Panxi River,as well as the bidirectional regulatory mechanism between nutrient levels and biofilm development.The findings deepen the understanding of the ecological role of biofilms in urban eutrophic rivers,provide important scientific support for further exploring the natural self-purification mechanism of eutrophic rivers,and offer valuable theoretical guidance for the ecological restoration and pollution control of urban river systems.关键词
水污染/基质/生物膜/营养盐/生物调控Key words
water pollution/substrate/biofilm/nutrients/biological regulation分类
资源环境引用本文复制引用
李宏,杨涛,胡建美,马媛媛,曾艺..河流基质附着生物膜与河流水质的相关关系及驱动路径[J].西部人居环境学刊,2025,40(5):32-37,6.基金项目
重庆市技术创新与应用发展专项重点项目(CSTB2025TIAD-KPX0050) （CSTB2025TIAD-KPX0050）
首创集团创新项目(SCHB202110) （SCHB202110）
