Changes in plankton abundance, biomass, and chemical composition under the influence of the cooling system of the Beloyarsk Nuclear Power Plant

The abundance and biomass of phytoplankton and zooplankton proved to noticeably decrease after the water passed through the cooling system of the Beloyarsk Nuclear Power Plant: the phytoplankton perished by 38% (65 metric tons per day), and the zooplankton, by 55% (6 t/day). In the period between 1985 and 1991, the concentration of⁶⁰Co in the plankton of water intake and discharge canals varied from 120 to 1400 Bq/kg dry weight, and that of¹³⁷Cs, from 150 to 1040 Bq/kg dry weight, which is commensurable with the content of radionuclides in the plants and grounds of the Beloyarsk reservoir. In 1985, it was noted that the plankton passing through the cooling system of the nuclear power plant became enriched with Ca, Fe, Mg, Mn, Co, Cs, Cu, Mo, Ni, Pb, Si, Sn, Ti, V, and W.     

长江荆江段浮游生物群落结构特征及其与环境因子的关系

为了解长江荆江段浮游生物的群落结构特征以及其与环境因子之间的关系，于2017年3、6、9和12月对荆江7个采样断面的左右岸共14个采样点的浮游生物群落结构及水文、水质参数进行了调查。结果表明：荆江采集到浮游植物7门67属135种(含变种)，以硅藻门（51.85%）和绿藻门（25.19%）为主。浮游植物的丰度均值为73.16×10 4 cells./L，生物量均值为0.87 mg/L，上荆江各采样断面间浮游植物丰度和生物量变化不明显，下荆江浮游植物的丰度和生物量表现从上游到下游逐渐增高的趋势。优势种为硅藻门的颗粒沟链藻和梅尼小环藻。Margalef 丰富度指数是0.83，Pielou均匀度指数是0.80和Shannon-Wiener多样性指数是1.90，下荆江的丰富度指数和多样性指数大于上荆江，说明上荆江比下荆江污染严重。典范对应分析溶氧、温度、氨氮是影响浮游植物群落结构的主要因素。浮游动物48属81种，其中轮虫最多（37.04%），其次是原生动物（25.93%）和枝角类（23.46%）。浮游动物丰度均值为6.32 ind./L，生物量均值为88×10-3 mg/L，上荆江浮游动物丰度和生物量低于下荆江。浮游动物优势种为冠砂壳虫、桡足类无节幼体和剑水蚤一种。Margalef 丰富度指数是5.2，Pielou均匀度指数是0.84和Shannon-Wiener多样性指数是1.32，下荆江的丰富度指数、均匀度指数和多样性指数均大于上荆江，说明上荆江比下荆江污染严重。冗余分析显示温度、溶氧和氨氮是影响浮游动物群落结构的主要因素。     

Patterns of the accumulation of chemical elements in the plankton of a fresh water body

For the first time, comparative data are presented on the distribution of 70 chemical elements occurring in the Beloyarsk Reservoir between the water and the plant and animal components of the plankton (phyto- and zooplankton). All these elements are ranked into groups according to the values of accumulation coefficient (AC) for phytoplankton and zooplankton. For the sum of all chemical elements, a significant positive correlation has been revealed between their content in the water and in the plankton. It has been shown that elements with even atomic numbers and concentrations in the plankton below 7 ??g/g dry weight are accumulated by the plankton in significantly larger amounts than such elements with odd atomic numbers. This fact confirms the classic concept developed by A.P. Vinogradov that the prevalence of chemical elements in the biosphere depends on their position in the periodic system.     

Effect of water-loving bird colonies on zooplankton in littoral zones of water bodies of different types

Changes in zooplankton developing under the effect of waste products from water-loving bird colonies were studied in water bodies of different types. The trophic status index in the nesting area showed no difference from its background values in an oligomesotrophic water body but was decreased in mesoeutrophic and eutrophic-hypertrophic water bodies. The abundance and biomass of zooplankton in the oligomesotrophic and mesoeutrophic water bodies were consistently higher than background values, while in the eutrophichypertrophic water body they were higher only at the beginning and in the middle of the nesting period. Irrespective of the trophic state of water body, the species diversity of zooplankton in the zone of impact from bird colonies was increased, but the number of dominant species remained unchanged, and no mass development of species indicating high organic load was observed; the proportion of Rotifera in the total abundance and biomass of zooplankton was decreased, that of Copepoda was increased, and the abundance of Cladocera was found to increase with the degree of overgrowing. Among possible explanations, this specific response of zooplankton is most likely due to changes in the ratio of nitrogen and phosphorus in the water.     

(137)Cs concentration in zooplankton and its relation to taxonomic composition in the western North Pacific Ocean

To study the role of zooplankton in the transport of (137)Cs in the ocean, zooplankton samples were collected in October 2005 and June 2006 in the western North Pacific Ocean. The peak zooplankton biomass was observed in the surface layer, and gelatinous plankton was more abundant in October 2005 than in June 2006 reflecting exchange of water masses. The concentrations of (137)Cs in zooplankton varied from 11 to 24 mBq kg wet(-1) and were higher in October 2005 than in June 2006. The elevated abundance of gelatinous zooplankton probably led to higher concentration of (137)Cs in zooplankton in October 2005. Annual export fluxes of (137)Cs by ontogenetic vertical migrant copepods were estimated to be 0.8 and 0.6 mBq m(-2) year(-1) at 200 and 1000 m depths, respectively; this suggested that transport of (137)Cs by zooplankton may be no trivial pathway.     

三峡水库春季浮游植物群落特征及影响因素

浮游植物群落特征是水域生态系统的一个基础信息,三峡水库作为长江经济带环境保护的重要区域,而关于三峡水库全水域浮游植物群落特征及其影响因素的研究报道仍不多见。为了解三峡水库浮游植物群落特征差异及影响因素等一系列基础信息,于2015年4月对三峡水库进行了大范围的调查,调查范围包括17个长江断面(共51个样点)及22条支流库湾(共122个样点)。结果显示:共采集到浮游植物7门39属61种,以绿藻门、硅藻门、甲藻门为主,其中绿藻门有26种,占据总种数的42.62%;硅藻门有16种,占据总种数的26.23%;甲藻门有7种,占据总种数的11.48%。丰度方面,硅藻门占绝对优势,比例为34.26%,其次是隐藻门(23.72%)、蓝藻门(20.96%)。生物量方面,则是甲藻门占绝对优势,其比例达到了44.18%,随后是隐藻门(29.92%)、硅藻门(14.32%)。丰度和生物量分别变化在2.22×10~4～5.12×10~(7 )cells/L和0.001 8～120.99 mg/L之间,且存在一致的趋势,从三峡大坝往长江上游,丰度值和生物量值逐渐增加。支流库湾浮游植物Shannon-Wiener多样性指数显著高于长江干流(Mann-Whitney U检验,P0.001)。冗余分析(Redundancy Analysis,RDA)表明,在长江干流中,水温(WT)、可溶性硅酸盐(DSi)是影响浮游植物群落结构的主要环境因子(P0.001);在支流库湾中,硝态氮(NO~-_3-N)、水温(WT)是影响浮游植物群落结构的主要环境因子(P=0.002)。该研究的成果有助于全面认识了解三峡水库长江干流和支流库湾春季浮游植物种类组成和影响因子,同时对三峡水库水资源管理和水生态保护具有一定参考价值。     

太湖五里湖沿岸带浮游植物群落生态特征(2014~2015年)

2014年7月~2015年6月对五里湖浮游植物开展了逐月调查，以研究综合治理后五里湖沿岸带浮游植物群落变化特征。本次调查共检出浮游植物8门196种，绿藻门物种最多(74种)，硅藻门次之(57种)。优势种共6门30种，其中2014年7、8、9、10月和2015年6月的第一优势种均为蓝藻门的小颤藻，其优势度范围为0.567~0.879。时间上，浮游植物密度和生物量的月均值变幅分别为1.07×106~2.18×108 ind./L，0.32~50.52 mg/L，其中由于蓝藻的大量增殖，夏和秋初密度、生物量极显著高于其他月份；空间上，A区浮游植物密度和生物量显著低于其余3个湖区。Pearson相关性分析表明，藻类密度、生物量和物种数与水体浊度(Tur)、pH和水温(WT)呈显著或极显著相关关系；RDA分析表明，WT、DO和Tur是与浮游植物群落结构相关性较强的环境因子(p<0.01)，其中相关性最强的为WT(r=0.8982)。依据浮游植物物种数和生物多样性指数对水质的分析表明：五里湖沿岸带水体处于中度富营养化水平。     

Effect of insolation and overhead canopy on macrozoobenthos of tropical freshwater ponds

Distribution and abundance of macrozoobenthic species were investigated in open and shaded sites of tropical freshwater pond ecosystems in Kolkata. Water temperature of open sites was higher than the shaded sites but transparency value was lower at the lighted sites presumably related with the production of phytoplankton in the presence of sunlight. Diversity of species was recorded highest (26 species) along with total benthos density (5999 no/m²) at slightly illuminated open site. Mean biomass was also highest at the slightly illuminated open site. Total benthos density of macrozoobenthos was lower at the fully shaded and fully lighted sites. The greater occurrence and abundance of most macrozoobenthic species-including total benthos density and biomass at the slightly illuminated open site was probably associated with microhabitat suitability supported by moderate presence of macrophytes. Higher quality food (algae and algal detritus) and thermal suitability as well as phototactic attraction of motile epibenthic gastropods and other organisms contribute to the greater abundance and production of biomass at this site.     

Composition and Some Ecological Features of Winter Zooplankton in Deep Stratified Lakes

For the first time, zooplankton and environmental factors have been studied in winter in the deep stratified lakes Siverskoe, Borodaevskoe, and Vydogoshch. The zooplankton consists of 18–22 species of rotifers, copepods, and cladocerans, including 15–18 specifically winter, cryophilic and eurythermic forms. The populations of zooplankters reproduce actively: males and egg-bearing females (in copepods), females with embryos and eggs in brood pouches (in cladocerans), and females with attached eggs (in rotifers) are present. In lakes Siverskoe and Borodaevskoe (depth 20–24 m), where oxygen deficiency is observed only in the bottom water layer, the zooplankton populates the greater part of the water column and forms a large aggregation in the oxycline and near the bottom. The abundance of bacteria in these zones is high (up to 4–6 × 10⁶ cells/ml). In Lake Vydogoshch (depth 16 m), oxygen deficiency extends to the middle layers, and all zooplankton is distributed above the oxycline. The biomass of winter zooplankton in Lake Siverskoe in 1983 averaged 1.26 g/m³, with a maximum of 4 g/m³; in 1993, 1.4 and 8.04 g/m²; the respective values in Lake Borodaevskoe were 0.98 and 3.1 in 1983 and 0.14 and 1.6 in 1993; in Lake Vydogoshch, 0.15 and 0.24 in 1983 and 1.25 g/m³ in 1993. The development of winter zooplankton is limited by the size of the zone of oxygen deficiency and depends on the amount of food (bacterioplankton). The distribution of zooplankton in the water column and its biomass in individual layers is determined by the rate of methane formation and oxidation.__________Translated from Ekologiya, No. 3, 2005, pp. 201–214.Original Russian Text Copyright © 2005 by Rivier.     

嘉陵江下游江段春季浮游藻类特征及污染现状

2006年春季,通过水质分析和浮游藻类调查,应用污生谱分析法及生物多样性指数法,对嘉陵江下游江段春季浮游藻类特征及污染现状进行了研究。结果发现,该江段共有浮游藻类7门42属85种（包括变种）;优势种群并不单一,以黄藻、绿藻和硅藻占优势,优势种为黄藻门中的黄丝藻,绿藻门中的小球藻和硅藻门中的小环藻。5月份藻类的种类和个数均比4月份有所减少,可能与5月份降雨量比4月份多有关;流速最快的石门大桥具有最低的藻类细胞密度,流速最慢的化龙桥具有较高的藻类细胞密度,说明流速对浮游藻类种类和数量产生一定的影响。嘉陵江下游沿岸一带的氨氮含量都很高,氨氮已经形成全江段水系的主要污染,磷酸盐含量也较高,均超过水体富营养化的氮、磷含量最低限制标准,该江段水质污染较严重。污生谱分析法及生物多样性指数法的评价结果表明,该江段整体污染状况为中度污染,农业和工业污染不容忽视。〖     

通江城市河道浮游植物分布研究——以镇江市古运河为例

为了解通江城市河道浮游植物分布动态规律，同时为制定有效的水环境质量改善方案，对镇江市古运河的浮游植物组成与分布变化进行现场调查与分析，探讨了环境因子变化对河道浮游植物结构与数量的影响。结果表明，研究区共检出藻类6门38属，其中绿藻门、蓝藻门和硅藻门为3个常见门类。河道内藻类细胞密度与生物量排序为春季>秋季>夏季>冬季。对比河源采样点，河道内藻类细胞密度、生物量均在春、秋季大幅增长，藻类种类组成比例也逐渐由硅藻门为主过渡到以绿、蓝藻为主，但在夏、冬季这种变化趋势不明显。水动力、营养盐浓度、水温以及水体悬浮泥沙含量等多环境因子影响了河道内藻类生长与繁殖条件，其中因受闸控影响的水动力学条件变化是造成藻类分布变化的关键诱发要素。〖     

Influence of global change on phytoplankton and nutrient cycling in the Elbe River

The effects of changing climatic and socioeconomic conditions on the water quality of the Elbe River were investigated using the deterministic model QSim. Since the impact of global change on river water quality marks the endpoint of various processes in the catchment and in the atmosphere, this study was performed within a network of interacting models that determined input parameters for water quality simulations. The development of phytoplankton and nutrient concentrations under conditions of global change was modeled along a 700 km stretch of the river. The simulations revealed a strong, scale-dependent effect of climate change on phytoplankton biomass, leading to a longitudinal shift of the dominating processes (primary productivity vs. respiration) along the river continuum. Under reduced flow, combined with increasing temperature and global radiation, phytoplankton biomass increased and phytoplankton maxima shifted in upstream direction, followed by higher system respiration rates in the adjacent downstream sections. In contrast, higher flow shifted the phytoplankton maximum toward the downstream sections. Even a drastic reduction of phosphorus inputs from anthropogenic sources had only limited influence on algal biomass, due to the ability of algal cells to store phosphorus. A strong reduction in P-inputs especially in the headwaters would be necessary to counterbalance the possible climate-induced effects on algal biomass.     

巢湖藻华易堆积区蓝藻时空分布的研究

巢湖西半湖采样分析结果表明夏季蓝藻水华主要集聚于湖滨带。因此选择西半湖藻华易堆积的区域，并监测在风力驱使下蓝藻水华的时空分布规律，分析湖滨带浮游植物生物量与理化因子的相关性。结果表明：湖滨带水华生物量的分布容易受到风向和天气的影响；水体的叶绿素a浓度与总氮（TN）、总磷（TP）和高锰酸钾指数（CODMn）呈显著的正相关（p<001）；湖滨带水体中微囊藻（Microcystis）的生物量几乎占据水体总浮游植物生物量的95%以上，而且越靠近湖岸带微囊藻的生物量所占的比例越大。据此，可以选择湖滨带水华易聚集区作为蓝藻水华尤其是微囊藻去除的重点区域，以有效地削减蓝藻水华污染，从而为巢湖水生态系统的修复创造条件     

三峡水库香溪河库湾夏季水华期间浮游植物的初级生产力

用黑白瓶法调查了香溪河库湾夏季水华期间浮游植物的初级生产力,探讨了浮游植物初级生产力的分布格局、光照强度对初级生产力的影响以及香溪河库湾浮游植物群落的代谢类型。结果表明:河口、峡口、吴家湾和平邑口总初级生产力最大值分别为6.33、3.89、6.51和4.67 gO2/(m2.d);平邑口、吴家湾、峡口、河口0~5 m水柱日生产量分别为6.95、6.78、5.17和4.65 gO2/(m2.d)。除平邑口的最大生产力出现在水下0.5 m以外,其余3个样点的生产力垂直变化均表现为表层最高,随水深增加而逐渐降低。吴家湾、峡口、河口三位点总初级生产力和净初级生产力与相对应水层的平均光照强度呈显著正相关,而平邑口位点相关性不明显。香溪河库湾1 m水深以内的群落代谢率平均值为4.0,推测夏季水华期间该水体1 m水深以内的浮游植物群落为自养代谢类型。     

Phytoplankton-nutrient relationships in years with various water levels in the Pasłęka River in the vicinity of the hydroelectric power station (North-east Poland)

Relationships between abundance of basic net phytoplankton taxonomic groups (cyanobacteria, diatoms, and chlorophytes) and nutrient concentrations in water were studied on the Pas??ka River in years with varied water levels. In high water level conditions, large amounts of orthophosphates and total nitrogen from the catchment could favor development of cyanobacteria and chlorophytes. The species could be allochthonic. At low water levels, the factor stimulating phytoplankton development could be nutrients coming from mineralization of accumulated organic matter. The highest nutrient concentrations could favor diatom development. In such conditions, dominant taxa were autochthonic. In terms of numbers, F. capucina was dominant, and in terms of biomass—genus Spirogyra sp. It could come from plant periphyton inhabiting the concrete drops of the dam included in the river’s development in the vicinity of the hydroelectric power station.     

苏皖交界河网区浮游植物群落结构及其与环境因子关系的研究

苏皖交界处的石臼湖是长江下游唯一的通江淡水湖,通过青弋江和姑溪河直接与长江相连,形成了复杂的河网水系。为探讨这种复杂的河网水系中浮游植物种群结构特征,2012年平水期和枯水期分别对石臼湖及其周边入湖支流进行了浮游植物调查,研究河网水系中河网与湖区浮游植物的种类组成、季节变化及与环境因子的关系。结果显示:共采集到浮游植物105种,平水期与枯水期种类数差别不大,两次调查均出现的种类约有70%相同;浮游植物丰度最高可达1×108cell/L,达到了水华暴发的标准。优势种类主要绿藻门和蓝藻门为主,但是从生物量来看硅藻门占优。排序分析显示河网区域浮游植物季节演替明显,且河网与湖区浮游植物群落结构差异明显,进一步分析则表明影响浮游植物主要的环境因子是氮、磷等营养元素。     

富营养湖泊中轮虫群落结构季节变化的环境驱动力研究(英)

通过对桥墩湖一周年的逐月采样,比较了影响轮虫群落结构季节变化的3种环境驱动力的相对重要性。桥墩湖是一个富营养湖泊,具有较高的营养盐和Chl a含量以及低的透明度。研究发现：水温和营养水平是影响轮虫数量和群落结构季节变化最重要的理化因子。由于大型枝角类数量的稀少,其对轮虫数量并没有显著的负面影响。短尾秀体溞是影响轮虫群落结构季节变化的最重要的枝角类;然而大多数优势轮虫与短尾秀体溞密度峰值的共同出现可能反映了它们对高营养水平和高水温的共同喜好。在浮游植物中,绿藻是决定轮虫密度的最重要的浮游植物门类;而其中的隐藻则是影响轮虫群落结构变化的最重要属。3组环境因子(理化因子、浮游植物、浮游甲壳动物)对轮虫群落结构的季节变化具有相似的解释大小。这些结果表明：在该富营养湖泊中,轮虫群落结构的季节变化可能主要受理化因子和食物资源的影响;浮游甲壳动物对轮虫群落结构的塑造作用有限     

蓝藻水华的拦截和陷阱捕获综合控藻技术研究

基于水文气象条件对巢湖蓝藻水华分布的影响，在西北岸万年埠的迎风岸湖段设置蓝藻水华拦截围隔和蓝藻水华捕获陷阱。通过连续监测，比较围隔内外蓝藻生物量和浮游植物多样性的差异，检测水华陷阱的蓝藻捕获效率，从而对蓝藻水华拦截和陷阱处置综合控藻技术的作用进行评估。结果表明：（1）陷阱设置在西半湖万年埠湖段是科学合理的，监测表明蓝藻水华生物量受风力和水流驱使主要聚集在沿岸带区域；（2）水华拦截围隔对蓝藻水华有很好的拦截效果，在水华暴发期间蓝藻围栏可以拦截50%以上的蓝藻水华和50% 以上的Chla浓度，水华拦截区围隔内的生物多样性指数显著高于拦截围栏之外的水域；（3）陷阱对微囊藻水华的聚集捕获效果显著，在适宜气象条件下聚集效率约为2 kg/(m2·d）。这些研究结果说明该综合技术有很好的控藻效果，具有良好的应用前景     

长江口水域浮游动物生物量及其年间变化

根据2000～2003年长江口邻近海域2个季节8个航次海洋调查资料,对长江口邻近海域浮游动物生物量及其年间变化进行研究。结果表明：5月高生物量分布区在交汇水团的海水一侧,而交汇水团的淡水一侧生物量较低。8月高生物量分布在交汇水团的两侧,交汇水团的生物量较低。长江口生物量的年间变动与外海水势力有关。高生物量分布区往往位于长江口水域的东侧,当外海暖水势力强盛时,高生物量分布区向长江口伸展,使整个水域浮游动物生物量增高,而当外海暖水势力较弱时,高生物量分布区范围缩小。2001至2003年浮游动物生物量逐年迅速降低与此有密切的关系。浮游动物优势种组成及丰度变化是影响长江口饵料生物量变化的重要因素。     

On the Classification of Aquatic Communities: An Example of Zooplanktonic Cenoses of Karst Lakes in the North of European Russia

Nine lakes in the Arkhangelsk oblast were analyzed with respect to their morphometry, hydrology, and hydrochemistry, and their zooplankton was studied for three years. The data on zooplankton abundance, biomass, the ratio of filter-feeders and predators, the Shannon index of species diversity, and average individual weight of zooplankters were obtained. Differences in the structure of zooplanktonic cenoses were revealed in lakes differing in morphometric parameters, prevailing ions (HCO₃ ^–, SO₄ ^2–), and their concentration.