珠江河口区某景观水体轮虫群落演替及水质评价

于2016年2—11月,对珠江河口区某景观水体轮虫群落的演替特征进行了逐月调查,并进行了多样性分析,同时探究了群落演替与典型环境因子之间的关系。经鉴定:共发现轮虫23种,隶属于6科15属。主要优势种为角突臂尾轮虫(Brachionus angularis)、螺形龟甲轮虫(Keratella cochlearis)、广布多肢轮虫(Polyarthra vulgaris)和暗小异尾轮虫(Trichocerca pusilla)。在时间尺度上,轮虫密度无明显的变化趋势,密度在107.2~3 637.5 ind/L之间变化,在3、6、9月出现密度高峰,2月最低;空间尺度上,不同位点轮虫密度在1 412.8~2 800.3 ind/L之间变化,景观水体(S2、S3、S4和S5)轮虫平均密度显著高于引河S1(p0.05)。Pearson相关性分析表明,轮虫密度与温度、叶绿素a浓度呈极显著正相关(p0.01),与盐度无显著相关性(r=-0.360,p0.05)。E/O、Q值(Q=B/T)和污染指示种评价均得出该景观水体处于中度富营养化水平,需加强后期的调控与维护。     

长荡湖浮游动物群落结构特征及影响因子分析

为了解长荡湖浮游动物群落结构特征以及与环境因子的关系,于2016年1～12月对长荡湖浮游动物和水质理化指标进行监测、分析。结果显示:长荡湖浮游动物共有48属74种,其中原生动物17属23种,占总种类的31.1%;轮虫15属30种,占总种类的40.5%;枝角类8属10种,占总种类的13.5%;桡足类8属11种,占总种类的14.9%。小型浮游动物(轮虫、原生动物)的生物数量和种类所占比例较高,而大型浮游动物(甲壳动物)所占比例较低。浮游动物生物密度年均为2653.6 ind./L,生物量年均为3.7027 mg/L。Pearson相关性分析表明:水温与角突臂尾轮虫、简弧象鼻溞和广布中剑水蚤呈极显著的正相关关系;p H与多肢轮虫呈显著的正相关关系,与钟形钟虫呈显著的负相关关系。     

海南秋季重点水库浮游动物群落结构特征研究

为掌握海南重点水库浮游动物群落结构特征,全面支撑海南省三大流域水生态调查研究工作,2022年11月对松涛水库、大广坝水库、牛路岭水库的浮游动物群落结构特征展开调查研究。结果显示,三大重点水库共鉴定浮游动物12科16属25种、 18科24属32种、 14科19属32种,优势种以球形砂壳虫、螺形龟甲轮虫、裂痕龟纹轮虫占主导。浮游动物丰度分别在992.98～1 875.11 ind./L、 1 878.36～2 667.38 ind./L、 30.13～18338.44 ind./L之间,平均值在1 497.14～6 663.68 ind./L之间,水库各站点存在明显差异。总体而言,大广坝水库的种类数整体较为丰富,生物多样性水平较高,水生态质量评价为良好,松涛水库、牛路岭水库的水生态质量状况整体评价为中污染状态。     

2020年洞庭湖水生生物群落结构特征及水生态评价研究

为了解洞庭湖水生生物群落结构并进行水生态评价，在2020年采用Shannon-Wiener指数对洞庭湖浮游植物、浮游动物和底栖动物进行调查，并采用水生态环境质量综合指数法(WQI)对洞庭湖进行水生态评价。结果表明：(1)洞庭湖浮游植物共检出6门73属，优势种类有伪鱼腥藻(Pseudanabaena sp.)、直链藻(Melosira sp.)、尖头藻(Raphidiopsis sp.)、平裂藻(Merismopedia sp.)和十字藻(Crucigenia sp.),全湖平均密度为95.7×10⁴个/L。(2)洞庭湖浮游动物共检出48属，优势种是广生多肢轮虫(Polyarthra vulgaris)、螺形龟甲轮虫(Keratella cochlearis)、象鼻蚤(Bosmina sp.)以及无节幼体(nauplius),全湖平均密度为74个/L。(3)底栖动物共检出57种，优势种类有指突隐摇蚊(Cryptochironomus rostratus)、多足摇蚊(Polypedilum sp.)、铜锈环棱螺(Bellamya aeruginosa)、河蚬(Corb...     

官厅水库浮游动物调查与水质评价

通过调查官厅水库不同样站浮游动物的生态状况，对官厅水库的水质污染进行评价。本次调查共检测到浮游动物105种，隶属于67个属。其中原生动物最多，共计59种，其次是轮虫35种，枝角类6种，桡足类及其无节幼虫5种。浮游动物在数量上具有原生动物占绝对优势，轮虫次之，枝角类与桡足类数量较少的特点。浮游动物的优势种群有急游虫Strombidiumuiride、螺形龟甲轮虫 Keratella cohlearis、矩形龟甲轮虫 Keratella quadrata、沟渠异足猛水蚤Canthocamptus staphylinus等。官厅水库浮游动物较丰富，大部分库区水体为中等污染，野鸭湖水体水质要优于官厅水库水体水质。     

陈桥东湖浮游生物群落结构特征及水质评价

陈桥东湖是新乡黄河湿地鸟类国家级自然保护区中部实验区的常年集水区之一,是许多珍稀鸟类的繁殖及栖息地,具有重要的生物多样性保护和潜在的科学研究、生态旅游价值。为了解陈桥东湖浮游生物群落结构特征及水质状况,于2017年1月、4月、7月和10月对陈桥东湖进行浮游生物采样调查,并利用浮游生物多样性指数评价水质状况。结果共发现浮游植物有8门67属118种,其中绿藻47种,种类最多,占39.83%;其次是硅藻,有35种;甲藻最少,只有2种。各采样点浮游植物丰度变化范围为(2.52~39.7)×10⁶ cells/L,全年主要优势门类为硅藻、绿藻和蓝藻。共发现浮游动物34种,轮虫种类最多,共21种,占61.76%;丰度变化为68~1 342 cells/L。全年轮虫为主要优势种类,轮虫滤食者RF为主要浮游动物功能群。浮游生物多样性指数结果显示陈桥东湖水体整体呈中度污染状况,且夏季最差,冬季相对较好,与水体理化指标调查结果一致。研究成果可为新乡黄河湿地水环境保护及生态修护提供参考依据。     

南京外秦淮河浮游动植物初步调查研究

对南京外秦淮河的浮游动植物种类、数量、生物量、优势种等进行了初步调查研究,共检出南京外秦淮河浮游植物5门37属43种,浮游动物3类12属13种.浮游植物平均数量为3 367.23万个/L,生物量为17.912mg/L,浮游动物平均数量为91.38个/L,生物量为4.171 mg/L.从外秦淮河上游到下游,浮游植物种类数、数量和生物量总体上逐渐递增,浮游动物种类数和生物量上、下游多于中游,数量也呈递增趋势.浮游植物优势种主要有微囊藻、颤藻、颗粒直链藻和团藻,浮游动物优势种有萼花臂尾轮虫、近亲裸腹溞和广布中剑水蚤,初步判定外秦淮河有机污染仍然严重,富营养化程度高.     

北京崇青水库浮游生物群落结构及水质健康评价

为了解崇青水库浮游生物群落结构和水质情况,于2017年和2018年夏秋两季(6月、9月)对北京崇青水库进行水质和生物调查,结果发现浮游植物共8门77种,平均密度5.61×106ind./L,生物量41.31 mg/L,属于绿藻-硅藻-蓝藻型水库,优势种为尖脆杆藻Fragilaria acus、普通小球藻Chlorella vulgaris;发现浮游动物共113种,平均密度1048ind./L,生物量1.40 mg/L,主要组成为原生动物和轮虫,优势种为小单环栉毛虫Di-dinium balbianii nanum、针簇多肢轮虫Polyarthra trigla、尖尾疣毛轮虫Synchatea stylata;浮游植物多样性指数H′为2.83,均匀度指数J为0.66;浮游动物多样性指数H′为3.35,均匀度指数J为0.70,利用基础饵料法估计水库鱼产力为4.3×106kg.综合来看,崇青水库水质总体状态良好,营养状态为中营养型;但氮磷含量较高,浮游生物富营养化指示种的出现,表示崇青水库有水质恶化的可能.     

海河口浮游动物多样性初探

调查研究了2014年5、8月海河口9个站点的浮游动物物种及其数量。海河口有浮游动物24种,以轮虫、桡枝足类为主,优势种为褶皱臂尾轮虫。各断面浮游动物平均密度5月为71.32 ind./L、8月为586.41 ind./L,夏季明显比春季有所提高。调查水域浮游动物的平均生物量5、8月分别为24.55、0.78 mg/L,5月高于8月,闸上高于闸下。浮游动物的各项特征与季节、所在水体盐度及营养盐状况有关。     

册田水库浮游生物资源调查

2011年5月—11月对册田水库浮游生物资源进行了全面调查。共检出浮游植物7门43种属,平均生物量50.37 mg/L,优势种群为蓝藻门、绿藻门和硅藻门。浮游动物4门26种,平均生物量为4.42 mg/L,优势种群为原生动物的板壳虫和轮虫。评价属重度富营养型水库。     

Seasonal Abundance of Planktonic Rotifers in a Nearshore Area of Central Lake Michigan

Thirty-four species of planktonic rotifers were recorded from east central Lake Michigan. Polyarthra vulgaris and Keratella cochlearis were the most abundant species recorded. Kellicottia longispina, Notholca squamula, Keratella earlinae, K. quadrata, and Synchaeta stylata were also important species. Maximum abundance occurred in June (360 Ind./L). July and August abundances exceeded 100 ind./L while spring and fall samples contained 10-20 ind./L. The species assemblage in east central Lake Michigan, western Lake Michigan, and Lake Ontario is similar. The eutrophic indicator Brachionus, abundant in western Lake Erie, was rare in this investigation.     

Contrasting zooplankton communities of two bays of the large,shallow, eutrophic Lake Taihu,China: Their relationship to environmental factors

Zooplankton are an important link in aquatic food webs of lakes serving as consumers of algae, bacteria, and other microorganisms and as prey for fish and invertebrates. Despite their importance, little is known about the structure of the zooplankton communities of subtropic, large, shallow, eutrophic freshwater lakes. Our investigation of zooplankton communities in Lake Taihu, a subtropic, shallow, eutrophic lake and the third largest lake in China provides new information on this subject. Zooplankton, phytoplankton, and water chemistry samples were collected monthly from July 2006 to June 2007 in Meiliang and Gonghu Bays of Lake Taihu. Thirty zooplankton species were identified in Meiliang Bay with small-bodied cladocerans Bosmina coregoni and Ceriodaphnia cornuta contributing 21% and 11%, respectively to total zooplankton abundance which averaged 459 ind/L. Thirty-five species were identified in Gonghu Bay with the rotifers Polyarthra trigla and Brachionus calyciflorus the dominant species, contributing 21% and 11% respectively to total zooplankton abundance which averaged 467 ind/L. Predation by lake anchovy (Coilia ectenes taihuensis) and ice fish (Neosalanx tangkahkeii taihuensis) likely accounted for the dominance of both bays by small-bodied species. Community structure and community patterns were correlated with differences in Microcystis blooms and organic matter levels (chemical oxygen demand) in the two bays. Based on canonical correspondence analyses dissolved total nitrogen, orthophosphate, Cyclotella and Pinnularia also contributed to variability in zooplankton community composition.     

Rotifer communities in the Laurentian Great Lakes, 1983–2006 and factors affecting their composition

Rotifer communities were examined from the open waters of the Laurentian Great Lakes between 1983 and 2006 in the first inter-lake comparison involving all five lakes. Seventy rotifer taxa were found in summer samples, although most (> 80%) individuals were drawn from the following taxa: Conochilus unicornis, Polyarthra vulgaris, Keratella cochlearis, Kellicottia longispina, Keratella crassa, Synchaeta spp., Polyarthra major, Ploesoma truncatum, Keratella earlinae, and Keratella quadrata. Distributions of Filinia longiseta and several species of Brachionus and Trichocera were restricted to regions of higher trophy, notably the western basin of Lake Erie, but most taxa were widely distributed, differing in relative dominance rather than presence or absence. Rotifer community structure appeared to respond in tractable ways to differences in trophic state, with the four most common genera exhibited the following preferences, in order of decreasing trophy: Polyarthra, Keratella, Conochilus, and Kellicottia. Recent oligotrophication in Lake Huron was reflected in decreases in Keratella dominance and increased dominance of Conochilus, while in Lake Michigan oligotrophication was associated with decreases in Polyarthra and Keratella and increases in Conochilus, and Kellicottia. In Lake Ontario, the appearance of the exotic predatory Cercopagis pengoi was strongly associated with dramatic reductions in Polyarthra, while more gradual sequential increases in the dominance of Keratella, Conochilus and Kellicottia were probably the result of decreasing trophic state. Bythotrephes was identified in multivariate analyses as correlating strongly with rotifer composition, although only in Lake Michigan was a clear relationship between the predatory cladoceran and rotifer species shifts observed.     

扬州境内湖泊浮游植物群落结构与环境因子的关系

2013年5月—2014年5月对扬州境内3个湖泊(高邮湖、邵伯湖和宝应湖)的浮游植物群落组成与水环境因子进行监测,运用相关系数法和典范对应分析(CCA)法分析了浮游植物群落结构与环境因子之间的关系。结果表明:3个湖泊的群落组成均主要以硅藻、绿藻为主要优势种群,群落结构的季节变化趋势较为相似;水温、N、P是影响3个湖泊浮游植物数量的主要环境因子;CCA分析结果表明,水温和TN是影响高邮湖浮游植物群落分布的主要环境因子,NH⁺₄-N、TP和pH是影响邵伯湖浮游植物群落分布的主要环境因子,COD_Mn、NH⁺₄-N和TP是影响宝应湖浮游植物群落分布的主要环境因子。     

Rotifer Seasonal Succession and Copepod Predation in Lake Michigan

Phytoplankton and zooplankton population dynamics in southeastern Lake Michigan provide indirect evidence that selective Cyclops predation and food resource levels are important determinants of rotifer species succession. The spring rotifer community, dominated by the soft-bodied Synchaeta, declined in abundance by late spring and was succeeded by a summer assemblage dominated by spiny (Kellicottia, Keratella) and colonial (Conochilus) rotifers, and then by an autumn assemblage of spiny rotifers and the soft-bodied, evasive-swimming Polyarthra vulgaris. In contrast to Synchaeta, these latter forms are resistant to predation by Cyclops bicuspidatus thomasi, the major invertebrate predator in the study area. The density of Synchaeta was negatively correlated with the population density of late instar C. bicuspidatus thomasi and positively correlated with standing stocks of flagellates and small, non-flagellate (<30 μm on one dimension) phytoplankton. These results suggest that Cyclops predation and food resource levels were important factors affecting the abundance of this genus. Conservative estimates of predation mortality of Synchaeta by Cyclops can account for most of the estimated population death rates during spring and early summer when Synchaeta abundances declined markedly. The population dynamics of rotifers resistant to Cyclops predation, especially Keratella cochlearis and Kellicottia longispina, were positively correlated with Cyclops populations, suggesting that abundances of these populations were not predation-limited. A high correlation between egg ratios of these resistant species and phytoplankton standing stocks was found. However, no significant correlation was observed between estimated death rates of resistant species and Cyclops abundance, suggesting that population dynamics of these predation-resistant species were more affected by food resources than by cyclopoid predation.     

长荡湖、滆湖、竺山湾藻类功能群结构组成与环境因子的关系

为研究太湖流域上游长荡湖、滆湖、竺山湾三大典型浅水湖泊藻类功能群结构组成与环境因子的关系,基于2019年2月至2020年10月水文、水质及浮游植物数据,采用Q指数、香农-维纳多样性指数、TLI综合富营养化指数分析了3个湖泊的水质状况,采用非度量多维尺度变换(NMDS)分析了浮游植物群落结构组成特征,采用冗余分析探讨了浮游植物功能群与环境因子的关系。结果表明：长荡湖和滆湖水质整体属于轻度富营养化,竺山湾除冬季外,均属于中度富营养化;长荡湖、滆湖、竺山湾分别有浮游植物7门61属96种、8门75属129种和6门53属124种,分别划分为9、10和11个优势功能群;3个湖泊藻类功能群变化的共同环境因子是水温、高锰酸盐指数和总磷,而总氮和氮磷比对3个湖泊功能群结构变化的作用并不明显。     

Spatial and temporal variations of dissolved CO2, CH4 and N2O in Lakes Edward and George (East Africa)

We report dissolved CO₂, CH₄ and N₂O concentrations in two large East African lakes, Edward (surface area 2,325 km², average depth of 37 m) and George (surface area 273 km², average depth of 2 m). Lake George showed modest seasonal and spatial variations, and lower partial pressure of CO₂ (pCO₂) (26 ± 16 ppm, mean ± standard deviation), CH₄ (234 ± 208 nmol/L) and N₂O saturation levels (%N₂O) (80 ± 9 %) than Lake Edward (404 ± 145 ppm, 357 ± 483 nmol/L, 139 ± 222 %). Surface waters in both lakes were over-saturated in CH₄, and Lake George was under-saturated in CO₂ while Lake Edward was slightly over-saturated in CO₂. This difference was related to higher phytoplankton biomass in Lake George than Lake Edward, with average chlorophyll-a concentrations of 177 ± 125 and 18 ± 25 µg/L, respectively. Permanent high cyanobacterial biomass in Lake George led to uniform dissolved CO₂, CH₄ and N₂O concentrations. In surface waters of Lake Edward, spatial variations of pCO₂, CH₄ and N₂O were related to bottom depth, and locally (in particular in Katwe Bay) also related to the inputs of water from Lake George via the Kazinga Channel, a 40-km natural channel connecting the lakes. Short-term mixing events related to storms increased CO₂, CH₄ and N₂O content in surface waters, in particular for CH₄ and N₂O. This indicates that mixing events in response to storms can create ‘hot moments’ for CH₄ and N₂O emissions to the atmosphere in tropical lakes, given the weaker vertical density gradients compared to higher latitude systems.     

Analysis of the correlations between environmental factors and rare cranes in the Poyang Lake region of China

Using survey data during 2001–2013 from a total of 38 lakes in the Poyang Lake region of China, we analyzed the inter-annual change in crane populations and the spatial distribution of crane species. Across the study sites, the total crane population was 6400 ± 2620 individuals during the period 2001–2013. Crane populations varied widely across the study sites: the largest crane population was observed on Bang Lake with an annual average of 2373, followed by Qi Lake, Dacha Lake, and Zhu Lake. The four main crane species, which were active on 50–80% of study lakes during the period of investigation, were G. leucogeranus, G. monacha, G. vipio, and G. grus. In particular, G. leucogeranus, G. monacha, and G. vipio were observed mainly in Poyang Lake National Nature Reserve and nearby lakes. G. grus was mostly observed in Poyang County. The largest populations of G. leucogeranus, G. vipio, and G. monacha were observed on Bang Lake, with annual averages of 1229, 985, and 88 birds, respectively. The largest G. grus population was observed on Qi Lake, with an annual average of 756 birds. We found that habitats for G. leucogeranus, G. monacha, and G. vipio were defined by similar environmental factors. In particular, increasing distance from roads had a positive impact on populations of these three species. By contrast, sedimentary total phosphorus content showed negative correlations with populations of all four main crane species, which implied that eutrophication could pose a threat to these rare crane species.     

A Seasonal Study Reveals the Occurrence of Exotic Rotifers,the River Antigua,Veracruz, Close to the Gulf of Mexico

Zooplankton studies in Mexican rivers are few despite the fact that Mexico has >200 rivers. We present data on the seasonal diversity of rotifers during 2013–2014 from the river La Antigua, near Veracruz. We collected samples from 15 stations along a horizontal gradient of ~5 km, from the upper reaches to about 2 km from the sea. The physico‐chemical variables analysed were temperature, pH, dissolved oxygen, conductivity, nitrates, phosphates, Secchi depth and salinity. From each site, 80 L of water was filtered with a 50‐μm plankton net. Rotifers were identified and quantified using a Sedgewick Rafter cell. The river is shallow (maximum depth 2.5 m during the rainy season). Our observations indicated that the phytoplankton community was dominated by diatoms; the chlorophyll a concentrations ranged from 0.55 to 26.1 μg L^?1 over the study period. We found >125 rotifer species belonging to 21 families, mostly from the Lecanidae, Brachionidae, Notommatidae and Lepadellidae. The density of rotifers was low, <40 ind. L^?1, but species diversity (Shannon–Wiener) ranged, except for a onetime minimum of 0.25, from 2.0 to 4.0 for most part of the year. We also encountered Notholca cf. liepetterseni , an endemic species to Europe and Lecane yatseni , endemic to Asia. Other new records included Lecane rhytida and Ptygura melicerta . The importance of long‐term studies in rivers is emphasized. Copyright © 2017 John Wiley & Sons, Ltd.     

Lake Corangamite, Australia, a permanent saline lake: Conservation and management issues

Lake Corangamite in western Victoria, Australia, is the largest permanent lake on the Australian mainland. Its levels and salinities fluctuated naturally until recently. Since about 1960, its major inflow creek has been diverted for management purposes and lake levels have fallen and salinities risen. The changes have been most profound since 1980. Since 1980, salinity has risen from ～35g/L to >50g/L, water levels have fallen by nearly 2m, and many islands have become peninsulas or have disappeared. The major effect has been a change in the composition of the biota from one that is characteristic of lakes in the region of moderate salinity (>35g/L) to one that is characteristic of more saline lakes (50-100 g/L). In particular, Austrochiltonia subtenuis (Amphipoda), Coxiella (Gastropoda), Galaxias maculatus (Pisces) and Ruppia (macrophyte) have almost disappeared. The loss of these species has greatly decreased the value of the lake to the avifauna in particular and as a natural resource in general. The changes to Lake Corangamite resulted largely from the diversion of the inflowing waters from the Woady Yaloak Creek, the major influent stream, into the Barwon River. The diversion scheme, undertaken by the Rural Water Commission of Victoria, was implemented mainly to minimize the possibility of flooding of land adjacent to the lake. The environmental consequences of such diversion were not fully considered. The paper documents the physico-chemical and biological changes that occurred up to 1992, and discusses issues of conservation and management interest associated with the changes. Changes in the level of Lake Corangamite and associated limnological features accord with the pattern observed in many salt lakes worldwide.