新开河4种水生植物表面附着微生物群落特征

以水生植物金鱼藻、伊乐藻、萍蓬草和菱角为研究对象,利用扫描电镜、荧光显微镜和16S rRNA高通量测序技术,探究不同水生植物表面微生物群落特征。结果表明:沉水植物表面附生藻类密度比浮叶植物的高,且植物表面附生藻类组成与周围水体明显不同;浮叶植物萍蓬草和菱角根部的微生物群落结构与其叶表面的差异较大。4种水生植物表面附着细菌群落优势门类依次为变形菌门、厚壁菌门、绿弯菌门、拟杆菌门、酸杆菌门和疣微菌门,具有水体污染物质净化功能;两种类型水生植物表面附着有大量微生物,且不同植物之间和同种植物不同器官之间的优势种存在一定的差异。     

北大港水库微生物群落的空间分布特征

天津北大港水库水质存在咸化问题，水质咸化可能会导致微生物群落组成和多样性发生显著变化。为探究 水质咸化条件下水库微生物群落组成的空间分布特征，于 2021 年 12 月在北大港水库采集表层、中层和底层的水 样，利用高通量测序技术，对北大港水库不同深度及上下游的微生物群落组成及多样性进行分析，并探究溶解性 总固体与微生物群落的关系。结果表明：北大港水库的溶解性总固体（total?dissolved?solids,?TDS）质量浓度在表层、 中层和底层存在差异，下游高于上游。微生物的主要优势菌门为变形菌门、拟杆菌门和放线菌门，变形菌门的相 对丰度均超过 50%。优势菌属是 Clade_III 未定属（相对丰度 1.10％～72.72?％）和黄杆菌属（Flavobacterium?相对丰 度 0.32％～20.09?％），Clade_III 未定属的相对丰度上游高于下游，黄杆菌属的相对丰度表层高于中层和底层。上 游水体表层的微生物群落组成与中层、底层的微生物群落组成存在显著差异，下游在不同深度微生物群落组成差 异不显著，中层和底层的微生物群落组成存在相似性。Chao1 和 Shannon 指数表现出表层<中层<底层，下游略高 于上游，微生物 Alpha 多样性指数随 TDS 质量浓度的增大而减小。在科水平上，Clade_Ⅲ能够耐受较高的盐度，但 当 TDS 质量浓度>3?000?mg/L 时其丰度降低。     

水生植物分布与保护——以荆州城区为例

一、水生植物的概念及分类水生植物,就是指生长在水中、或对水分的要求和依赖比较强的植物。根据水生植物的生活方式,一般将其分为以下几大类:挺水植物、浮叶植物、沉水植物和漂浮植物。挺水型水生植物植株高大,花色艳丽,绝大多数有茎、叶之分;直立挺拔,下部或基部沉于水中,根或地茎扎入泥中生长,上部植株挺出水面。挺水型植物种类繁多,常见的     

水生植物-生物膜体系的生态功能与互作机制研究进展

水生植物是水生态系统的重要组成部分,是生物膜的天然载体,水生植被的恢复有利于提高水体生物膜面积。与非生物介质相比,水生植物与微生物间存在附着互作机制,一方面水生植物能为微生物提供附着场所和营养物质,其产生的化感物质对附着微生物的种类和数量有影响;另一方面,附着微生物也会对水生植物生长产生促进或遏制作用。另外,指出水流和水质对水生植物及生物膜的形成、结构以及群落组成产生重要影响;水生植物和生物膜作为一个复杂互作体系,是水体生态系统的基本单位,相关植物表面-表面生物膜体系特征及其对水体中碳、氮等要素的转化及污染物的去除机制相关研究,将是今后水生态研究过程中的重点方向之一。     

北京妫水河水生植物群落调查与水质响应关系研究

作为典型的北方缺水河流,妫水河生境脆弱,特别是城区段受人为干扰强烈,水生植物群落退化严重。通过开展妫水河水生植物群落实地调查和水质监测,摸清不同河段水生植物群落分布与水质之间的响应关系,有利于区域水生植物群落的重新构建。妫水河现有水生植物12科12属14种,其中,挺水植物6种(42.9%),沉水植物6种(42.9%),浮叶植物1种(7.1%),漂浮植物1种(7.1%)。不同河段水生植物群落结构存在显著差异,在水质较好的山区型河段(古城河和妫水河干流龙顺路附近)主要分布有以沉水植物为主的菹草+水毛茛+金鱼藻群落和浮萍﹣金鱼藻群落;在水质较差的城区型河段(三里河)主要分布有耐污性较强的香蒲+菖蒲群落、菰+芦苇+水芹﹣菹草群落;在缓坡型河段(蔡家河和妫水河干环湖南路附近)分布有以挺水植物为主的芦苇+香蒲﹣狸藻﹣荇菜群落和菰+香蒲﹣眼子菜群落。以群落分布规律为依据,可为妫水河生态修复提供思路和设计参考。     

汉江上游干支流沉积物细菌群落多样性和影响因素

为了解汉江上游干支流沉积物细菌多样性以及确定性过程和随机性过程在沉积物细菌群落构建过程中的相对重要性,基于Illumina高通量测序技术,分析了环境因子对细菌群落组成的影响,采用非度量多维尺度(NMDS)排序探究了季节之间沉积物细菌群落的差异,并结合中性群落模型和标准化随机率量化了确定性过程和随机过程对群落构建的影响。结果表明:汉江上游及其支流细菌群落主要由变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、蓝藻门(Cyanophyta)、浮霉菌门(Planctomycetes)和酸杆菌门(Acidobacteria)等组成；细菌群落在不同季节有显著差异；地理距离和环境因子对细菌群落结构影响较小,确定性过程并未在细菌群落组成中起到主导作用；随机过程很大程度上影响了群落在秋季和春季的组成,是沉积物细菌群落构建的主导因素。     

基于大凌河流域水质评价研究

文章将综合指数法与主成分分析法相结合客观、科学的评价了大凌河流域水质状况,对各单项指标客观权重利用主成分法赋权并用于综合水质评价,通过对比分析其他水质评价方法验证了该方法的可行性与合理性。研究表明:大凌河流域各区段水质等级在时空分布上存在明显的差异,评价结果与流域水质实际状况基本相符;改进的水质标识法能够客观、准确的反映流域各区段在不同时间上的水质达标情况,具有较强的可操作性与科学性。     

基于河道护坡技术的水土保持治理效益评价——以辽宁大凌河流域为例

为了解决大凌河流域水土流失严重状况,针对当地的水土流失采取了以全系列生态护坡、土壤生物工程和复合式生物稳定技术为主的河道生态护坡技术。选择将层次分析法和Topsis法两者有效结合的方法,针对大凌河流域水土保持工作效益进行了全方位评价,得到如下结论:水生植物面积、治理面积、林地面积是整个大凌河流域水土保持治理效益评价体系的关键点;整个大凌河流域的水土流失现象被有效控制,整体态势向良性发展。层次分析法和Topsis法两者有效结合是科学可行的,适用于各个地区的水土保持工作效益评价工作。     

不同类型浮床对水质的净化效果研究

生态浮床作为一种环境友好型的水污染治理方法,相对物理化学方法具有较大的优势,自提出以来越来越被广泛关注.目前,生态浮床技术在理论和应用方面都有较深入的研究,但主要集中在植物选择、污染物的去除效果和机理,以及各种创新型浮床,并未将生态浮床作为一个完整的微生态系统进行研究.本文根据植物和微生物的空间分布,模拟设置植物—微生物复合生态浮床系统,研究植物-微生物复合生态浮床、植物浮床和微生物对水质的净化效果,复合生态浮床内部植物和微生物间的相互作用、相互影响.结果表明,不同类型浮床对TP具有较好的去除效果.植物浮床和复合浮床对TP的去除效果均高达90%.复合浮床、植物浮床、微生物处理对水体TN的去除率分别为55.3%、31.2%、31.1%.植物、"植物+微生物"、"植物+空白载体"处理组对植物株高和地径的影响依次变大,主要原因是微生物在富集和形成初期,与植物之间存在养分竞争,影响植物的生长.     

多种修复技术对城市内河水质及微生物群落的影响

采集城市内河水样,分别采用曝气增氧、碳源添加、生物投菌和综合修复等技术,在实验室进行水质修复模拟实验,并以水质参数、微生物多样性及丰度为鉴定指标,分析不同修复技术对城市河流水质的修复效果及其对河流微生物群落结构的影响。结果表明,曝气、生物投菌和综合修复技术可以提高河流微生物群落结构多样性,水体微生物群落以变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)和疣微菌门(Verrucomicrobia)为主;而使用碳源添加技术的水样,河流微生物的多样性下降明显,变形菌门(Proteobacteria)的相对丰度达到了93%;水质修复方面,曝气增氧技术和生物投菌技术都仅能降低水体COD质量浓度,无法降低水体TN及NH+4-N质量浓度;碳源添加和综合修复技术,对水体TN和NH+4-N的去除效果明显,但投加碳源的河流水体中的COD质量浓度显著上升;相关性分析结果表明,影响水体微生物群落结构的主要环境因子为COD和DO。     

Spatial patterns of bacterial community composition within Lake Erie sediments

Lake Erie is a large freshwater ecosystem with three distinct basins that exhibit an east-to-west gradient of increasing productivity, as well as allochthonous inputs of nutrients and xenobiotics. To evaluate microbial community composition throughout this ecosystem, 435 16S rDNA environmental clones were sequenced from 11 sediment samples throughout the Western, Central, and Eastern basins, as well as the hypoxic “dead zone” of Lake Erie in the hypolimnetic region of the Central basin. Rank abundance distributions of bacterial taxa within each location revealed that Gamma- and Betaproteobacteria, microbes capable of metabolizing a wide range of organic matter pools, comprised a greater fraction of the microbial community within inshore sites of the Central and Western basins compared to the Eastern basin. While geophysical characteristics of the three major basins and the dead zone did not drive significant differences in species diversity, Fast UniFrac analyses revealed microbial community spatial structuring, with the Central basin showing higher phylogenetic uniqueness of bacterial lineages. Principal component analyses based on phylogenetic distances consistently grouped the dead zone with the Central basin and highlighted the distinctiveness of microbial communities from the Eastern basin. Results from this study provide evidence for the local adaptation of microbial communities and the potential role of riverine inputs in modulating taxonomic composition of lacustrine bacterial communities. These results are consistent with previous functional studies on microbial metabolism, which showed that differences in geochemistry across the three basins of Lake Erie play an important role in the local adaptation of microbial communities.     

Influence of river plumes on the distribution and composition of nearshore Lake Michigan fishes

River plumes form in coastal areas where tributaries mix with their receiving waters. Plume waters are enriched with terrestrial-derived nutrients from their watersheds creating hotspots of biological productivity. The biological importance of plumes scales with the size and persistence of the plume; therefore, large, persistent plumes are more important than small, transient plumes. To date, most studies of plumes have focused on assimilation of terrestrial-derived energy by aquatic species or lower-level food web effects, primarily in marine systems. Few studies have described fish communities near plume habitats and compared them to non-plume areas, especially for the numerous small plumes in the Laurentian Great Lakes. Here we demonstrate that small plumes in the main basin of Lake Michigan enhance local primary productivity and influence distribution and abundance of nearshore Great Lakes fishes. We found that plume fish communities were relatively depauperate and did not support higher biological diversity of fishes compared to non-plume areas. However, individual species including rainbow smelt Osmerus mordax, spottail shiner Notropis hudsonius, and white sucker Catostomus commersonii were more abundant around plumes. Our results demonstrate that small plumes in the main basin of Lake Michigan support highly localized hotspots of biological productivity and fish abundance, primarily within 2?km of river mouths.     

巢湖水环境水生态现状问题分析及对策建议

依据 2017 年—2020 年巢湖健康状态报告,重点分析评价了导致巢湖处于亚健康状况的水环境、生物两类关键要素。巢湖处于亚健康状况的主要原因是入湖污染负荷量大、湖体氮磷营养盐浓度和蓝藻密度较高、水生植物稀少、鱼类小型化。提出巢湖治理必须综合施策,分区施策,分类施治,重点削减西半湖污染物通量和修复湖区生态。在强化流域水环境监管的同时,进一步深化南淝河、派河等重点污染入湖河流综合治理;尽快研究解决湖区污染物进出不平衡和持续增加的问题,找出各环境因子变化与水体富营养化变化、藻密度、水华程度、水华规模之间的内在联系,建立定量关系,制定重点污染因子消减对策和蓝藻水华控制措施。充分论证巢湖水生植物群落恢复方案,进一步加大湿地和水生植物建设和维护力度。开展巢湖水质生物调控和污染底泥控制试点工程,有计划地开展鱼类结构优化调控,保持水体生物链的健康发展。     

A floodplain spring: An ecotone between surface water and groundwater

Ecotones may be viewed as boundaries separating adjacent resource patches. They are dynamic components of the aquatic landscape and in the alluvial floodplain they occur as both diffuse and concentrated zones between surface and groundwater environments. This study is focused on a floodplain spring whose water supplies a backwater of the upper Rh6ne River alluvial floodplain (Iles Nouvelles). This paper analyses the community structure on both sides of the physical boundary separating the two ecosystems in relation to hydrological characteristics. The contact between two different environments (surface water and water-saturated sediment) creates a physical discontinuity which is of great importance for the distribution of aquatic fauna. Two types of organization are described: (1) within the sediment body there are mixed communities (epigean and hypogean) which can move with hydrological variations (biological ecotone) and (2) within the surface-water body there is a typical epigean fauna which displays a ‘border effect’. The ecological implications of the various patterns of biological responses are discussed as well as the regulatory aspect of the ecotone which minimizes the washout of hypogean fauna towards the surface ecosystem.     

Ecological assessment of the Selenga River basin,the main tributary of Lake Baikal,using aquatic macroinvertebrate communities as bioindicators

The Selenga River is the main tributary of Lake Baikal (Siberian, Russia). In 2015/2016, the water quality at previously identified contaminated hotspot regions in the lower Selenga River basin was evaluated using resident aquatic macroinvertebrate communities as bioindicators. Benthic macroinvertebrate communities within the Selenga River were found to be relatively sensitive to water pollution as was highlighted by three evaluated biotic indices:Average Score per Taxon (ASPT); Ephemeroptera-Plecoptera-Trichoptera density index (EPT); and Trent Biological Index (TBI). The human impact on the Selenga River basin water quality was evident due to the significant decrease of the biotic indices at several sample locations including downstream of the wastewater discharge point of Ulan-Ude city, in the Dzhida River downstream of the confluence of the Modonkul River, and especially in the Modonkul River near to the mining operations at Zakamensk. At the same time, our study revealed a high self-regeneration ability of the aquatic ecosystem throughout the basin; with resident benthic macroinvertebrate communities appearing to recover in both the Selenga River and the Dzhida River within two to five km downstream of the contamination source. The changes in the benthic communities at the Selenga delta sampling sites were shown to occur under the influence of natural factors such as hydrological conditions and benthic sediment type, which significantly changed from the upper to the lower regions of the delta. For the Selenga delta, a typology of benthic macroinvertebrate communities including a map of their spatial distribution is presented.     

3组水生植物对滏阳河营养盐去除效果研究

以滏阳河邯郸段3种水生植物狐尾藻、金鱼藻及篦齿眼子菜为研究对象,通过批式实验,考察植物种类对削减滏阳河原水污染物质的效果,研究3种植物及对照系统对氮、磷、COD_(Mn)等的去除效果。结果表明:经40 d批式实验后,各组反应器对TN,NH_3-N,TP,COD_(Mn)的去除率达62%,64%,42%和67%以上,其中净化效果最佳的植物为金鱼藻;同时,不同植物的含氮量与含磷量与其污染物去除能力不一一对应,但其大小次序与对氮、磷的去除能力基本相似,这可能与植物的吸收作用或植物根系微生物的代谢作用相关。     

Watershed-scale landuse is associated with temporal and spatial compositional variation in Lake Michigan tributary bacterial communities

Populations of stream organisms across trophic levels, including microbial taxa, are adapted to physical and biotic stream features, and are sentinels of geological and hydrological landscape processes and anthropogenic disturbance. Stream bacterial diversity and composition can have profound effects on resident and migratory species in Great Lakes tributaries. Study objectives were to characterize and compare the taxonomic composition and diversity of bacterial communities in 18 rivers of the Lake Michigan basin during April and June 2019 and to quantify associations with stream and watershed physical features and dominant landuse practices. River water was filtered, and genomic DNA was extracted from filtrate using antiseptic techniques. We performed high-throughput amplicon sequencing using the highly variable V4 region of the 16S rRNA gene to characterize microbial community composition and diversity. Effects of landscape-scale landuse, environmental variables and dispersal predictors (e.g., inter-stream distance) on community compositional differences were quantified. Greater than 90% of variation in bacterial relative abundance between rivers and time were attributed to 11 phyla representing 10,800 operational taxonomic units. Inter-stream geographic distance, stream hydrology, and variation in stream properties that were tied to patterns of watershed landuse were significantly associated with differences in bacterial community composition among streams at both sampling time periods. based on Bray-Curtis distances. Understanding how environmental characteristics and watershed-scale landuse influence lower trophic level stream communities such as bacteria will inform managers as biological indicators of ecosystem health, sources of disturbance, and current and future bottom-up trophic changes in coupled tributary-Great Lakes ecosystems.     

流域初始水权分配有关问题的研究

松辽流域的大凌河流域、霍林河流域省（自治区）水量分配方案的制定,已进入协调阶段.在初始水权分配过程中,涉及流域水资源承载能力、水量分配中时空特征选择、对效率和公平的理解等,对这些问题的广泛研究探讨,是在水量分配方案编制过程中的必经阶段.这些问题涉及水资源承载能力的自然属性和经济社会属性.     

典型滩涂环境因子对植物群落空间分布的影响

长江口滩涂生境具有较高的环境异质性,导致不同滩涂植物群落的分布特征存在显著差异。为分析长江口典型滩涂植物群与环境因子的关系,在崇明东滩和奉贤金汇港两个典型滩涂对其环境因子及植物群落特征进行了采样分析。分析结果表明,滩涂随着高程的增加,受潮汐的影响逐渐减少,环境因子呈现一定的规律性变化,滩涂植物对环境因子具有不同的适应力是导致长江口盐沼植被带状分布的重要因素。崇明东滩作为植物群落较为成熟的滩涂,芦苇和互花米草的生长表现沿高程呈"V"型。奉贤金汇港作为植物建群较短的新生带滩涂,互花米草的生长表现沿高程呈梯度分布。两区域植物群落表现不同的主要原因有可能是建群时间、演替阶段、滩涂受潮汐作用和立地条件等造成的。