黄河中游支流无定河流域源头区浮游生物和底栖动物群落特征与环境因子分析

为探究无定河流域源头区河流浮游生物和底栖动物的种类、数量、多样性等群落结构特征和环境因子的关系,以无定河流域源头区干流红柳河以及两条重要支流海流兔河和纳林河为研究对象,对河流浮游生物与底栖动物进行野外调查采样,采用Shannon-Wiener多样性指数、典范对应分析(CCA)等方法分析了无定河流域源头区浮游动植物和底栖动物群落特征及与环境因子的关系,识别影响群落分布的关键影响因子。结果显示:无定河源头区浮游生物和底栖动物较为丰富,共监测到浮游植物7门51种,以蓝藻门为优势门;浮游动物23种,以原生动物为优势门;底栖动物5门20科36种,以扁形动物门中的涡虫为优势种。支流的生物种类、数量和多样性指数均优于干流,上游均优于下游,其中纳林河生物多样性最丰富。典范对应分析的生物群落与水质关系表明,氨氮、COD和总氮是影响无定河流域源头区浮游生物和底栖动物群落结构的主要水环境指标。综合生物多样性指数与水体理化指标评估无定河源头区目前水质状况为中污染。     

蚂蚁河大型底栖无脊椎动物及其与环境响应关系研究

本文通过典型对应分析(CCA)和相关分析研究了大型底栖动物群落结构和主要环境因素之间的相关性,并通过生物多样性指数(如Shannon-Wiener指数)评估了不同河段对物种多样性的影响。研究表明,蚂蚁河中的大型底栖动物分布主要影响环境因子有水温、溶解氧和底质层中沙泥含量,与下游相比,蚂蚁河中上游的底栖动物物种多样性更高,平均生物密度更低。     

里下河地区典型湖泊大型底栖动物与环境因子的相关性分析

为揭示里下河地区湖泊大型底栖动物群落现状及其主要的环境影响因子,于2013年4月对里下河地区4个典型浅水湖泊的大型底栖动物群落进行了调查,并测定分析相关水质环境因子;对大型底栖动物群落与环境因子进行冗余分析,找出了对大型底栖动物群落影响较大的环境因子。结果表明:研究区域湖泊均处于富营养化状态,大型底栖动物群落分布趋向于单一化,铜锈环棱螺和霍甫水丝蚓是该地区典型湖泊的主要优势物种。冗余分析排序中,排序轴前两轴特征值较大,为0.168和0.115,合计0.283,分别解释了42.6%和31.8%的物种-环境变异,PO3-4-P、Chl-a和DO是对大型底栖动物密度影响较大的环境因子。     

昆承湖大型底栖动物时空分布及对环境修复的指示性

2015年对常熟市昆承湖的大型底栖动物进行了时空分布调查,开展了水质生物学评价与环境影响因子分析,并基于底栖动物分布特征对昆承湖2006—2012年环境修复工程效果进行初步评估。结果表明:4次调查共采集底栖动物12科22种,优势物种多为耐污型;底栖动物年均密度为38.3 ind/m~2,各季节密度分布存在差异,但均以摇蚊幼虫类密度占优,其次为寡毛类和软体动物,底栖动物年均生物量为24.54 g/m~2,主要为软体动物所贡献;底栖动物Shannon-Wiener多样性指数值(H')、Margalef多样性指数值(D)、Pielou均匀度指数值(J)和BI指数值表明,昆承湖总体处于中度污染状态;不同湖区因污染程度等环境因素不同,底栖动物物种、密度与生物量分布存在差异,典范对应分析表明水体DO、浊度、TN、TP等水质因子以及底泥TN、总有机物等是影响底栖动物分布的主要环境因子;昆承湖实施封闭湖泊口门、深度清淤等环境修复措施后,水质总体得到改善,但湖泊水深增大、基底形态单一以及水生植物分布少等因素也影响了湖泊底栖动物密度与种群分布。     

西南水电站建成后底栖动物与环境因子的灰关联分析

底栖动物作为河流生态系统的组成部分,在物质与能量转换中发挥着重要的作用,水库的修建对底栖动物的影响日益受到关注。本文通过收集水电站建成后的底栖动物及其环境因子的数据,采用灰关联方法确定底栖动物的关键环境制约因子,计算分析得到总磷与底栖动物关联度最高,关联度0．6828。通过有效控制关键环境因子,促进底栖动物群落多样性的维持,对于维系河流生态系统的健康具有重要的现实意义。     

长荡湖底栖动物群落结构及与环境因子关系

为了研究长荡湖底栖动物群落结构组成以及影响因子,与2018年1—12月逐月对长荡湖湖区10个采样点进行了调查分析。长荡湖底栖动物共检出13种,主要为寡毛类、摇蚊幼虫以及软体动物3大类;通过优势度指数结果表明长荡湖底栖动物优势种为颤蚓(Tubifex)、黄色羽摇蚊(Chironomus flaviplumus)、刺铗长足摇蚊(Tanypus punctipennis)和梨形环棱螺(Bellamya purrificata); RDA多元统计分析结果显示,TN、CODMn、水深和总溶解固体是影响底栖动物优势种的主要水环境因子。     

渭河流域水生态系统健康评价

渭河系黄河最大支流,渭河流域河流水生态系统健康与黄河高质量发展息息相关。2011—2013年在渭河流域进行了4次野外采样调查,共布设采样点77个,采集鱼类、底栖动物、着生藻类和水环境因子等信息,分析了渭河流域水生态系统特征,并采用生物完整性指数法对渭河流域水生态系统健康进行了评价。渭河流域共采集到鱼类51种,底栖动物116种,着生藻类248种,影响渭河流域鱼类群落结构的环境因子为海拔,影响底栖动物群落结构的环境因子为河宽、电导率和硬度,影响着生藻类群落结构的环境因子为河宽。水生态系统健康评价结果表明:底栖动物和着生藻类健康状况优于鱼类,超过80%的采样点处于一般以上健康水平;3种生物水生态系统健康评价结果整体趋势相同,渭河干流上游和右岸支流、泾河源头以及北洛河中游支流健康状况较好,渭河中游和下游地区、泾河大部分区域以及北洛河上游健康状况较差。     

基于GAM模型的硅藻群落与环境因子相关性分析

底栖硅藻水质生物监测技术是被广泛研究与使用的一种监测河流水质及生态质量的理想手段。通过将CCA排序和GAM分析两种方法相结合,分析了对龙江区域河流附生硅藻群落分布影响较大的环境因子。GAM模型画出了各个水环境因子对硅藻完整性指数IBI的响应机制,偏CCA分析进一步确认了营养盐因子对河流硅藻群落的重要性。将两种方法的结果进行比较,最终得出营养盐和电导率是影响龙江附生硅藻群落结构变化的主要因子,流速和水温为次要影响因子。两种分析方法相结合增加了结果的可靠性。     

浅水湖泊底栖动物栖息地模拟

为研究白洋淀水生生物栖息地适宜度,分别于2016年春、夏、秋3季进行了实地考察和采样,结合野外观测和实验室测量得到环境和生物信息。基于14个采样点的数据,通过构建广义可加模型(GAMs)模拟和预测底栖动物的分布。使用Margalef指数作为响应变量,采用向前逐步回归筛选解释环境因子,通过评价剩余偏差来判断模型的表现。水深、水温、底泥氨氮、底泥有机质和沉水植物生物量被用于建立最终优化的广义可加模型。Margalef指数对环境因子的响应曲线表明该指数与水深和底泥氨氮浓度成线性负相关,与水温和底泥有机质浓度成线性正相关,而与沉水植物生物量是单峰关系。结果表明,预测值与实测值呈现显著的强相关性(Pearson R~2=0.847,P0.001),均方误差较小(MSE=0.013),模型性能表现良好。     

赣江干流底栖动物群落结构与环境因素的关系

底栖动物是河流水生态系统的重要组成部分,对水环境的变化极其敏感.为分析赣江干流底栖动物群落结构特征及其与环境因素的关系,本研究于2018年8月、2019年1月及4月在赣江干流布设12个采样点进行底栖动物调查.赣江干流共检出底栖动物3门6纲24种属,上游的优势种分别为苏氏尾鳃蚓和铜锈环棱螺,中游的优势种为铜锈环棱螺和河蚬...     

小浪底水库下游浮游生物及细菌群落对水沙调控的响应规律

浮游动物、浮游植物和细菌群落广泛分布于河流生态系统,发挥着初级生产者、初级消费者和分解者的重要作用,对于环境条件的波动较为敏感。本文于2018—2019年黄河小浪底水库调水调沙前、中、后期对下游河流进行了调查采样,得出水环境因子、浮游生物与细菌群落的定量结果,以明确在不同调水调沙阶段下游河流水环境因子,浮游生物和细菌群落的演变规律及相互作用。通过结构方程模型(SEM)和基于距离的冗余分析(dbRDA)、分别明确了调水调沙影响下浮游生物以及细菌群落对水环境因子的响应规律。结果表明,调水调沙不同阶段下,浮游植物、浮游动物和细菌对于环境因子的响应方式具有较大的差异,溶解氧(在调水调沙前影响系数最大,为0.86)、温度(在调水调沙期间影响系数最大,为0.76),以及电导率(调水调沙后影响系数最大,为0.82)等环境因子对浮游生物的生物量影响最明显,而溶解氧(在调水调沙前)和叶绿素a(调水调沙期间至调水调沙后)对于细菌群落的影响最大。此外,调水调沙过程改变了浮游生物群落内部关系,削弱了浮游动物对浮游植物的捕食,同时也使得悬浮和沉积状态的细菌群落在样点之间的差异性增大。本研究明确了浮游生物及细菌群落在水沙调控不同阶段下对水环境因子的响应规律,对下游河流生态修复具有一定的理论意义。     

微动力曝气技术应用于黑臭水体治理的参数优化研究

为了得到微动力曝气技术在黑臭水体治理过程中优化后的条件参数及预测模型,以曝气量、曝气时长和曝气位置为自变量,脱氮效果(氨氮消除时长和总氮削减率)为响应变量,根据Design-expert设置了17组试验。在试验过程中考虑内源污染释放等因素,然后以试验数据为基础,结合响应面模型分析,研究得出优化后的条件参数和预测模型。研究结果表明:两个响应面模型调整后的拟合度分别为0.99和0.96,预测模型的拟合度为0.95和0.69,具有良好的拟合度;优化后的条件参数曝气量为1 L/min、曝气时长12 h/d和曝气位置位于上覆水中部;此试验组下的氨氮消除时长和总氮削减率分别为5.50 d±0.00 d和51.84%±1.14%,与预测模型的预测值相比较,两者标准差分别为0.00%和0.98%。最终得出结论:优化条件参数后的微动力曝气技术应用于黑臭水体治理可以取得较好脱氮效果,模型可以较准确地预测水体修复效果。     

Bioassessment of Benthic Macroinvertebrates in Wetland Habitats of Lake Saint-Pierre (St. Lawrence River)

We evaluated the potential of vegetation and sediment habitats in wetlands of the St. Lawrence River for developing a macroinvertebrate bioassessment program with reference conditions. During September 2004, we collected macroinvertebrates in emergent vegetation and sediment in both fluvial sites (reference) and tributary-plume sites (impacted) in waters of the north and south shores of Lake Saint-Pierre (St. Lawrence River). In each habitat, we compared taxa richness, abundance, and community structure of macroinvertebrates between reference and impacted sites, and used multivariate models to relate macroinvertebrate community to environmental conditions. Each habitat was suitable for discriminating reference fluvial sites from impacted tributary-plume sites based on macroinvertebrate communities. In emergent vegetation, macroinvertebrates were dominated by epibenthic fauna such as crustaceans (Gammaridae, Asellidae) and molluscs (Valvatidae) at fluvial sites, and insect larvae (Chironomidae, Caenidae) at tributary-plume sites. In sediment, macroinvertebrates comprised a greater proportion of endobenthic fauna such as Oligochaeta and Sphaeridae. Crustaceans and molluscs were still dominant at fluvial sites and Oligocheata and Chironomidae at tributary-plume sites. No strong difference was depicted in macroinvertebrate composition between north and south shore water masses. Environmental variables explained a higher proportion of variance in macroinvertebrate community composition in emergent vegetation than in sediment (68% versus 44%). Macroinvertebrate composition in sediment was more related to metal contamination, whereas macroinvertebrate composition in emergent vegetation was related primarily to vegetation type and water quality. Relevance of the study for bioassessment of macroinvertebrates in the St. Lawrence River using the reference condition approach is discussed.     

Influence of environmental factors on abundance and temporal variation of benthic fauna resources in the eutrophic Tha Chin estuary, Samut Sakhon province, Thailand

The influence of environmental factors on the abundance and temporal variation of benthic fauna resources was studied in the eutrophic Tha Chin estuary located in Samut Sakhon province. The objectives were to analyze the status of abundance and temporal variation of the benthic fauna and to clarify the impacts from environmental factors (water and sediment quality). Field surveys were conducted monthly from August 2007 to March 2008 at 11 sampling stations in the estuary. Based on freshwater runoff volumes, the high-, medium-, and low-loading periods were categorized to be from August to October 2007, November to December 2007, and January to March 2008, respectively. The benthic fauna resources were composed of 57 species in eight phyla. Annelids were the dominant species (with the maximum density being 19,885 individuals/m2), followed by the mollusks. Both densities decreased during the low-loading period in 2008. Water quality deteriorated during the high-loading period. Land-based wastewater discharges decreased the levels of salinity and dissolved oxygen but dramatically increased various nutrients. Consequently, the sediment quality deteriorated during the medium-loading period. Bottom deposits during this time depicted high accumulation of acid volatile sulfides (more than 0.76 mg/g dry weight). Analyzing the environmental relationships, deposit feeders (for example, Nereis sp. and Prionospio sp.) and a clam (Arcuatula sp.) showed potential as bio-indicators for environmental monitoring. The overall results revealed the importance of changes in the water and sediment qualities that had an influence on related benthic resources. The increase in the level of NH4(+)-N had a negative impact on the economic clam species, while the sedimentary TOM showed positive correlation (P < 0.05) with this increase. The succession of groups based on feeding behavior seemed to correspond with stress in eutrophication along the salinity gradient and in different estuarine parts. In addition, the economic clam population decreased noticeably during the medium-loading period, as a consequence of deteriorated sediment conditions. Thus, the land-based runoff should be controlled for the protection of resources. Further effective sustainable management will be enhanced by giving serious consideration to an eco-based zoning scheme for conservation and restoration of the Tha Chin estuary.     

Benthic Community and Sediment Quality Assessment of Port Hope Harbour,Lake Ontario

Sediments in Port Hope Harbour, Lake Ontario, have been heavily contaminated by radionuclides and heavy metals from a radium recovery plant, a uranium refinery, and other industrial activities. Spatial patterns in surficial sediment contamination, benthic community structure, and bioaccumulation of contaminants were assessed to determine possible relationships and potential environmental hazards in the event of dredging. Benthic community differences in species composition and density between inner and outer harbour areas corresponded with both habitat and sediment quality differences. Sediment loss-on-ignition, nitrogen, iron, copper, lead, chromium, zinc, and nickel concentrations in the inner harbour exceeded provincial guidelines for open water disposal of dredged spoils. Only iron exceeded those guidelines in the outer harbour. Tissue levels of radionuclides and heavy metals in benthic invertebrates were greatest at the most heavily contaminated stations in the inner harbour. Reduced benthic densities and maximum sediment contamination occurred near a refinery cooling water discharge.     

白洋淀浮游生物群落动态变化与生物量模拟研究

为探究白洋淀浮游生物群落结构动态特征及其关键影响因子，基于2017年秋，2018年春、夏3个季节的水环境因子与浮游生物野外采样调查结果，采用冗余分析(ＲDA)、广义可加模型(GAMs)等方法探究了白洋淀不同季节的浮游生物群落动态变化，建立了浮游植物生物量与环境因子的非线性关系并进行了率定验证。结果表明:与1992年白洋淀干淀后重新蓄水时相比，浮游植物与浮游动物物种数分别下降了59%与37%，优势群落从绿藻门转化为蓝藻门。根据ＲDA排序结果可知，温度、透明度是影响浮游生物丰度的关键环境因子。运用GAMs构建了环境因子与浮游植物生物量的定量模型，最优模型结构为Biomass-phy～s(T)+s(TN)+s(Cond)+s(Biomass-zoo)+s(Biomass-pro)+te(Biomass-pro_TN)+te(Biomass-pro_Cond)+te(Biomass-pro_Biomass-zoo)。将2019年6月采样数据进行模型验证，计算模拟效果良好，实现了对浮游植物生物量的定量模拟，能够为白洋淀生态恢复与保护提供决策支持。     

Changes in the benthic communities of Muskegon Lake,a Great Lakes Area of Concern

Sediment contamination resulting from the direct discharge of industrial and municipal wastes contributed to the designation of Muskegon Lake (Michigan) as a Great Lakes Area of Concern. To assess the changes occurring in the sedient-dwelling invertebrate communities since wastewater diversion began in 1973, benthic samples were collected three times per year (spring, summer, fall) between 2004 and 2010 from six sites and compared to historic samples. The density and diversity of invertebrate populations were analyzed to: 1) identify spatial and temporal patterns in the community structure; 2) determine if community structure patterns were related to environmental variables; and 3) assess the recovery of Muskegon Lake's benthic community following wastewater diversion. Our results revealed that invertebrate community structure changed on both annual and spatial scales, while seasonal differences were shown to be modest between 2004 and 2010. The environmental variables with the greatest explanatory power included dissolved oxygen, pH, and depth. Overall, recovery of benthic invertebrate community structure was evident based on multiple lines of evidence, including increased densities of all major taxonomic groups and species diversity since wastewater diversion, decreases in both the oligochaete–chironomid ratio (0.92 in 1972; 0.69 in 2010) and the proportion of oligochaetes, and declining sediment metal concentration over time. However, comparisons of present-day and historic sampling sites must be viewed with caution because sampling locations and protocols varied among years. Significant changes in benthic invertebrate composition and water quality metrics since 1972 suggest improved environmental conditions and the continued recovery of Muskegon Lake from historic pollution.     

Effects of stream hydraulics and other environmental variables on density of Narapa bonettoi (Oligochaeta) in the Paraná River system

Hydraulic and substratum conditions have been identified as two stream features which affect the benthic community composition, abundance and distribution. However, little attention has been given to the influence of hydraulic variables in large river beds. The aim of this study was to analyse the incidence of the near‐bottom hydraulic conditions and other environmental variables on the density of Narapa bonettoi (Oligochaeta, Narapidae), a typical and dominant species found in sandy bed rivers of diverse hierarchy of the Paraná River basin. A large amount of existing and available benthic data were used. The highest correlations among N. bonettoi densities and environmental variables were obtained with the hydraulic variables of friction Reynolds number (R_*) and shear stress (τ₀); the substratum type (sand, silt and clay) and organic matter content. The results show that N. bonettoi density would be related with the hydraulic variables following a ‘bell‐shaped’ tendency, e.g. with the friction Reynolds number, N. bonettoi would have a preference for transition values of turbulence (～40 < R_* < ～50), which is equivalent to τ₀ between ～0.6 and ～0.8 kg ^?2. Densities show a slight decreasing tendency toward the maximum R_* values, suggesting that the species does not support a completely developed turbulence (R_* > ～70). Significant but negative correlations were reported in the literature between benthic macroinvertebrates typical of smaller and steeper streams and R_* values far beyond the threshold 70 value. N. bonettoi shows a clear preference for a completely sandy substratum and for sand particles sizes around 300 µm. Finally, considering the important role played by the hydraulic variables on the benthic community studied herein, the contagious distribution pattern of N. bonettoi, reported by other authors, would be principally linked with the interactions between current and sediment near the bottom rather than with the mobility of these organisms. Copyright © 2008 John Wiley & Sons, Ltd.     

伊通河城区段底栖动物完整性对水质的响应时滞

基于2015年和2019—2021年伊通河长春市城区段底栖动物调查及水质监测数据,建立底栖动物完整性指数（benthic-index of biotic integrity, B-IBI）评价体系,对伊通河城区段水生态健康状况进行评价,并在此基础上确定影响B-IBI的关键水质指标及两者间的响应时滞。结果表明：伊通河城区段底栖动物种类数在月际间无显著差异性（P>0.05）,但在年际间差异显著（P<0.05）,种类数先减少后增加,主要类群由耐污种向清洁种转变;2015—2021年,伊通河城区段B-IBI年均值波动上升,河流健康整体呈逐渐好转趋势,且上游河段健康状况优于下游;各项水质指标中,总磷对伊通河城区段B-IBI值及其核心指标有显著性影响,且底栖动物对总磷质量浓度变化的响应在时间上存在滞后性,滞后时间为9个月左右（r=-0.88）。研究可为城市河流健康评价和治理管理提供科学依据。