用硅藻群集指数(DAIpo)和河流污染指数(RPId)评价珠江广州河段的水质状况

用硅藻计于1990年采集珠江广州河段的9个采样点的附着硅藻群落．共得硅藻24个属,170个分类单位,其中,适腐性种8个,广腐性种84个,仍腐性种78个．群落相似性聚类分析表明,位于前、后航道中部的员村（st3）,新造（st8）,沙浴村（si10）三点的硅藻群落结构是为相似,向上,下游相似性逐渐减小．用硅藻群集指数（DAIpo）和河流污染指数（RPId）对各采样断面的水质进行分析表明：大盛（st12）和莲花山（st5）两点受污染最轻,属β-寡污带,黄沙点（st2）污染最严重,属α-中污带．对照点鸦岗（St1）也受到一定的污染,属α-寡污带,其它点的污染程度在α-寡污带与β-中污带之间．DAIpo值与BODS存在着显著的负相关（r＝0．86）．珠江广州河段的前、后航道的污染程度相差不大（RPId=56．42,56.26）,均属中度污染．     

嘉陵江南充段硅藻群落结构及水环境分析

为了揭示嘉陵江流经南充A段5县（市）受到的污染及水质状况,按枯水期、平水期和丰水期采集研究15个采样点的硅藻样品,分析其群落结构的物种组成、细胞密度、多样性指数和均匀度指数等,并结合化学指标对水质状况进行评价。结果表明：（1）嘉陵江南充段共有硅藻136种（含变种和变型）;细胞密度介于4500--39000ind／L之间,总平均18213ind／L;（2）硅藻物种数、细胞密度、均匀度指数及多样性指数等呈现出显著季节性和水平分布上的差异;（3）嘉陵江南充“段水质总体上属于β-中污水体,具有一定的自净能力。其中,阆中水质最好,属清洁水体;南部、仪陇和蓬安水质有所下降,介于β-中污与清洁水体之间;南充水质较差,属α-中污水体。     

白及根部内生真菌多样性研究

白及是地生兰科多年生草本植物,是常见的中草药之一。白及根是白及植株吸收养分和水分的主要场所,开展其根部内生真菌的群落组成及多样性分析,对了解云南原生境白及与根部内生真菌间的共生关系具有重要意义。本研究采用形态学和ITS rDNA分子系统发育分析相结合的方法进行菌株鉴定。结果表明,3个采样点的白及根部分离到可培养内生真菌32株,包括9个目、13个科、16个属。其中木霉属Trichoderma、镰刀菌属Fusarium、拟盘多毛孢属Pestalotiopsis为优势类群,分别占总物种数的21.88%、18.75%、9.38%;中碳垫菌属Nemania、丛赤壳属Nectria、炭角菌属Xylaria、紫霉属Purpureocillium、刺盘孢属Colletotrichum、黑孢子菌属Nigrospora、Biscogniauxia、腐质霉属Humicola、脉孢菌属Neurospora、拟茎点霉属Phomopsis、植物腐霉Phytopythium、毛霉属Mucor、伞状霉属Umbelopsis为常见内生真菌类群。α多样性指数分析表明：各采样点的白及根部内生真菌物种多样性最高的是昆明市水源保护区采样点（D=0.799,H’=1.698）,保山市龙陵县采样点物种多样性最低（D=0.787,H’=1.580）。β多样性分析采样点之间的Jaccard（0.912-0.993）、Bray-Curtis（0.838-0.986）和UniFrac（加权0.618-0.631;不加权0.770-0.799）距离,结果表明3个采样点之间的内生真菌群落组成存在差异。3个采样点的不同地理环境和土壤类型给白及提供了不同的生境条件,是影响白及根部内生真菌物种丰度和群落组成差异的主要因素之一。     

河南南湾水库浮游硅藻的种群结构与水质污染评价初步研究

通过对南湾水库6个采样点浮游硅藻分析,该水库硅藻61个种及种下分类单元。用多样性指数(H′)、均匀性指数(E)及硅藻优势种生态谱分析,对水质进行了初步评价。结果表明,南湾水库水质属清洁-轻污染等级。     

广东鉴江水系底栖硅藻多样性与时空分布特征

为了解广东省鉴江水系底栖硅藻多样性和时空分布特征,对全流域进行了底栖硅藻采样调查。结果表明,从19个采样点4次采样中共检出底栖硅藻10科52属242种,其中舟形藻属(Navicula)、菱形藻属(Nitzschia)和异极藻属(Gomphonema)是优势类群,出现频次和相对丰度较高。硅藻多样性指数(丰富度、真香农多样性指数和真辛普森多样性指数)随河流等级呈现一定的空间分布特征,但它们季节变化不明显。底栖硅藻群落相异性在上游和下游河段较高,从一级到三级河流递减,四级河流又增加。底栖硅藻群落结构空间变化明显,季节变化显著。群落丰富度的稀疏曲线表明,热带河流底栖硅藻群落以400个体计数,不能完整反映底栖硅藻多样性。这些为鉴江水系河流健康监测和水生态保护奠定了基础。     

白洋淀轮虫群落结构特征

选取白洋淀8个采样点于2005年9月—2006年12月对轮虫群落进行定性定量分析,共检出轮虫110种,采蒲台种类数最多,其次是枣林庄,南刘庄最少;从季节来看,春、秋轮虫种类数量最多,夏季其次,冬季最少;根据优势种比较,臂尾轮虫科、迈氏三肢轮虫、针簇多肢轮虫、龟甲轮虫属等甲型-中污性和乙型-中污性水体种类分布在污染较严重的南刘庄,而单趾轮属、腔轮属、鬼轮属等清洁种类则分布在采蒲台、枣林庄、烧车淀等淀区。除端村外,各采样点轮虫密度和生物量于2006年4月出现最大值。根据Q(B/T)指数评价白洋淀各采样点水质,南刘庄属富营养,圈头属寡营养,其它样点属中营养水质。白洋淀轮虫的Shannon-Wiener指数以及均匀度指数则在夏秋季较高,春季较低,而物种多样性指数并不能完全反映白洋淀各采样点的水质。     

白洋淀轮虫多样性及群落结构的初步研究

于2006年12月、2007年3～5月调查了白洋淀9个采样点的轮虫种类组成、数量及优势种,并对轮虫群落的多样性指数和群落相似性系数进行了测算,综合评价了白洋淀水质及富营养化状况.本次共发现轮虫41种,平均丰度为607～5024 ind./L,优势种为蒲达臂尾轮虫Brachionus budapesllensis、长肢多肢轮虫Polyarthra doli-choptera、角突臂尾轮虫B.angularis、矩形龟甲轮虫Keratella quadrata等,均为耐污性种类,各样点轮虫群落具较高相似性.从轮虫群落Margalef多样性指数看,白洋淀水质属中度污染和严重污染状况.     

嘉陵江四川段藻类植物群落结构及水质评价

为了揭示嘉陵江四川段藻类植物的群落结构特征和水质现状,分别于枯水期(1月)和丰水期(9月)沿江段至上而下分析了12个样点藻类群落的种类组成、Shannon多样性指数（H′）、Pielou均匀度指数（E）和Margalef丰富度指数（d).结果表明: 嘉陵江四川段共采集到藻类植物8门42科95属171种(包括变种),其中硅藻、绿藻和蓝藻为各样点的优势类群.整个江段枯水期藻类植物的平均细胞密度为14.71×10⁴ ind·L^-1,金溪和红岩子样点的密度最高,分别为28.33×10⁴和25.40×10⁴ ind·L^-1;群落中以硅藻的物种数量最为丰富.丰水期藻类植物的平均细胞密度为10.78×10⁴ ind·L^-1,以青居样点的密度最低,仅3.31×10⁴ind·L^-1,绿藻和蓝藻物种数量有所增加.整个江段12个样点枯水期和丰水期的平均d、平均H′和平均E分别为2.35、1.60、0.31和2.57、2.09和0.39.嘉陵江四川段的藻类植物群落结构、细胞密度、多样性指数和均匀度指数的时空分布格局差异显著.水质整体为中污染型,其中金溪和沙溪样点为寡污型或β中污型,水质较好;苍溪、红岩子、新政和青居样点水质较差,属α中-污型.     

嘉陵江小三峡硅藻群落结构及水环境

为了研究嘉陵江小三峡硅藻群落结构及水质状况,按枯水期（2006年11月—2007年3月）、平水期（2007年4—6月）和丰水期（2007年7—9月）分别采集6个样点的硅藻样品,分析其物种组成、细胞密度、多样性和均匀度指数及硅藻商等,并结合理化指标对水质进行评价。结果表明：嘉陵江小三峡共有硅藻78种（含变种和变型）,隶属2纲、10科、20属;硅藻细胞密度为0.53×10⁴～3.58×10⁴ ind·L^-1,总平均1.55×10⁴ ind·L^-1;多样性指数值（H′）为1.62～2.96,总平均2.33;均匀度指数值（E）为0.28～0.56,总平均0.42;嘉陵江小三峡水质总体上属β-中污水体,沙溪、北温泉水质较好,属微污水体,碚石、牛石沱水质次之,为β-中污水体,盐井、毛背沱水质最差,为α-中污水体。     

扎龙湿地硅藻植物群落季节变化及其对环境的响应

扎龙湿地位于黑龙江省西部、松嫩平原乌裕尔河下游,是我国北方同纬度地区最完整的湿地。于2012年春、夏、秋3季,对扎龙湿地6个代表性区域进行硅藻标本采集,经观察鉴定,发现硅藻植物140个分类单位,包括121种19变种,隶属于2纲6目9科30属。羽纹纲物种较丰富,占总种类数的95%。硅藻植物群落呈现明显的季节演替,秋季硅藻种类丰富度及相对丰度明显高于春、夏两季,优势种多以淡水、半咸水、喜弱碱的种类为主,优势种与水体的盐度和酸碱度存在一定的响应关系。应用典范对应分析(Canonical Correspondence Analysis,CCA)探讨硅藻植物群落变化与环境因子之间的关系。CCA结果显示在扎龙湿地中,水温、电导率、pH、溶解氧是影响硅藻群落结构变化的主要因素,此外总氮、总磷也是硅藻群落季节演替的重要驱动因子。结合硅藻植物多样性指数和硅藻商对扎龙湿地水质进行综合评价,结果显示扎龙湿地整体为中-寡污带水体,部分水域水质较清洁,少数样点受人为因素影响,呈轻污染。     

嘉陵江下游硅藻群落结构及物种多样性研究

于2006 年11 月, 2007 年2 月、5 月和8 月, 分别采集嘉陵江下游8 个采样点藻类样品, 分析其硅藻群落结构及物种多样性, 并利用物种多样性指数及硅藻商等对水质进行了生物学评价。结果表明: (1)共发现89种硅藻, 硅藻细胞密度变幅为0.57×104—4.51×104 ind/L, 总平均2.31×104 ind/L; 多样性指数值变幅为0.72—3.12, 总平均2.20; 均匀度指数值变幅为0.15—0.52, 总平均0.36; 硅藻商变幅为0.66—9.48, 总平均3.24。(2)硅藻群落结构呈现出季节和水平分布上的变化。在季节变化上, 物种丰富度、细胞密度及多样性指数等以温度较低的春(5 月)、秋(11 月)两季最高, 而以夏季(8 月)最低。在水平分布上, 从上游到下游, 硅藻群落结构呈现出物种丰富度、多样性指数值逐渐减小, 而细胞密度和硅藻商逐渐增加的趋势。(3)嘉陵江下游水质总体为β-中污水体。其中位于城市上游的云门、沙溪、温塘峡、井口水质较好, 为微污或β-中污水体, 而位于城区及下游的合川、毛背沱、磁器口和朝天门水质较差, 为α-中污或污染水体。       

Impact of Urban Pollution from the Hanoi Area on Benthic Diatom Communities Collected from the Red, Nhue and Tolich Rivers (Vietnam)

The effects of urban pollution from Hanoi city on the benthic diatom communities of the Nhue–Tolich river system were studied during the 2003 dry season. Benthic diatoms were allowed to grow on glass slides suspended in the water flow for 4 weeks. To reveal the relationship between water quality and diatom communities, Canonical correspondence analysis (CCA) was used on data concerning relative abundances of diatom species and environmental variables. Two diatom indices, IPS and DAIpo, were applied to evaluate water quality in the three rivers. A total of 291 diatom taxa were found in the Red, Nhue and Tolich Rivers. These were mainly cosmopolitan taxa, with some tropical, subtropical and endemic taxa. The most abundant taxa at the Red site were Aulacoseira granulata, Achnanthidium minutissimum, Encyonema minutum, Navicula recens and other halophilous taxa such as Nitzschia kurzii, Seminavis strigosa, Entomoneis paludosa, Bacillaria paradoxa. Diatom assemblages at the Tolich site consisted mainly of Nitzschia umbonata, Nitzschia palea and Eolimna minima. Diatom density ranged from 660 to 30,000 cells/cm². Environmental variables and diatom assemblage composition at all sites were significantly correlated. Two diatom indices gave similar results and indicate the Tolich River with the lowest values as a highly polluted site.     

Aquatic pollution assessment based on attached diatom communities in the Pinang River Basin,Malaysia

The diatom communities collected from artificial substrates (glass slides) at 12 sampling sites along Pinang River Basin were analysed. Species composition was highly variable among sampling sites, and the highest diversity value (mean H = 3.56 bit/individual) and species richness (mean S = 17.32) was recorded at a polluted station in an estuary, which received salt-water intrusion during high tide. The downstream sampling stations were heavily organically polluted with Saprobic Index values ranging between 2.81 and 3.10, while upstream stations were relatively clean with Saprobic Index values recorded between 1.40 and 1.96. The diatom community structure and the specific sensitivity of certain diatom species can be related to the degree of water quality in Pinang River Basin. The abundance of certain diatom species could be used as biological indicators to measure impacts of river pollution.     

Dynamics of diatom colonization process in some rivers influenced by urban pollution (Hanoi, Vietnam)

Periphytic diatom communities’ colonization patterns were studied at three sampling stations of the Red–Nhue–Tolich hydrosystem presenting different urban pollution levels by using artificial substrates for 6 weeks in dry season 2005. Structural characteristics of periphytic diatoms developed on glass substrates at each sampling site were followed and compared. This experiment showed, through various general criteria (total diatom density, dry weight biomass) and specific criteria (relative diatom abundances, indices) that the structure of benthic diatoms developed on these substrates was strongly affected by pollution as early as the second week of colonization. Communities exposed to heavily and moderately polluted sites contained species which are known to be saprophilous or tolerant to organic pollution such as Nitzschia umbonata, Nitzschia palea, Cyclotella meneghiniana, Eolimna minima. Growth inhibition of diatom communities at the heavily polluted site was mostly related to a strong increase of organic load rather than to low metallic input, though metallic (Cd and Zn) burdens have been successfully quantified in the biofilms developed at the three studied sites. Nevertheless, no significant difference in species richness and diversity index between colonization duration times was observed. Based on values of diatom indices Indice de Polluosensibilité (IPS) and diatom assemblage index to organic water pollution (DAIPo), water quality could be classified as medium quality at Red site, polluted at NT₂ and heavily polluted at TL. Thus, the use of diatoms as a tool for water assessment appears suitable for monitoring rivers in Vietnam, as it is in several other countries.     

Responses and structural recovery of periphytic diatom communities after short-term disturbance in some rivers (Hanoi, Vietnam)

Field transfer experiments of periphytic diatom assemblages developed on artificial substrates were set up to assess the responses of those communities to environmental disturbances. The glass slides were positioned for colonization at the relatively unpolluted site (Red, in the Red River) and at the heavily polluted site (TL, in the To Lich River) in the beginning of the experiment. After a period of 2?weeks, the colonized glass slides were concomitantly transferred from the unpolluted Red site to the heavily polluted TL site and to the moderate polluted site (NT₂, in the Nhue River) and, conversely, from the TL site to the Red site, and then to the NT₂ site. The responses and the adapting capacity of periphytic diatom communities to environmental changes were assessed through the cell density, diversity index, species richness, taxonomic composition, and diatom indices after 2 and 4?weeks of transfer periods. For all transfers except for the transfer from the Red to the TL site in which the growth inhibition of diatom cells was found, the diatom density significantly increased until the end of the experiment. Thus, the diatom communities have expressed their pollution tolerance or sensitivities by changing their composition to adapt themselves to environmental changes. Characteristic species of the Red site (Gyrosigma scalproides, Navicula recens) were replaced by Nitzschia palea, Nitzschia umbonata, Aulacoseira granulate typical species of the NT₂ site, in the biofilm transferred from the Red site to the NT₂ site. The relative abundances of typical diatom species of the Red site proliferated in the biofilm transferred from the TL site to the Red site. The replacement of periphytic diatom communities appeared after the transfer from the second week at the different sites. The slow shift of the species towards the typical species at the TL site could result from the organized structure of diatoms within biofilm before the transfer from the Red site to the TL site. The shifts in values of the Index of Specific Polluosensitivity and Diatom Assemblage Index to organic pollution throughout the experiment indicated the clear sensitivity of these indices to water quality changes.     

大夏河临夏段肉鞭虫群落结构特征及其与水质的相互关系

2005年2月-2007年3月对大夏河临夏段的肉鞭虫物种多样性和分布特征进行了研究.结果表明:大夏河临夏段的肉鞭虫共记录135种,隶属于5纲16目,其中优势类群为眼虫目(Euglenida)和变形目(Amoebida);大夏河临夏段同一水期不同采样点之间以及不同水期同一采样点之间群落相似性系数均较低,均表现出明显的空间异质性;肉鞭虫群落结构特征表明,大夏河临夏段水体已受到不同程度的污染,枯水期较丰水期污染严重.     

Ecological survey of the aquatic oligochaetes in the Lower Pearl River (People's Republic of China)

The species composition, distribution and abundance of the Tubificidae (8 spp.) and Naididae (at least 4 spp.) in the Guangzhou reach of the Lower Pearl River were investigated. Limnodrilus spp. (particularly L. hoffmeisteri) constitutes the greatest part in nearly all samples, which were taken in both clean and polluted parts of the reach. In the polluted sites, total oligochaete densities reach values of up to 700 000 ind. m^–2. The importance and problems of using oligochaetes as indicators of organic pollution are discussed.     

珠江浮游真核微型生物分子多样性及其与水环境的关系

文章分别在丰水期和枯水期于珠江广州段和西江广东段43个样点采集水样, 基于末端限制性长度多态性分析, 研究了珠三角地区珠江水体的浮游真核微型生物的分子多样性及其群落结构和水体理化因子的关系。结果表明, 西江广东段及珠江广州段水体氮和磷严重超标, 水质状况堪忧。枯水期样本浮游真核微型生物香农威尔多样性指数普遍高于丰水期样本, 西江广东段样本浮游真核微型生物多样性指数普遍高于珠江广州段样本。不同水期, 不同区域的浮游真核微型生物群落结构均存在显著差异。珠江样点的浮游真核微型生物群落结构均与化学需氧量、高锰酸盐指数、氨氮、总氮、总磷高度相关; 但不同水期、不同区域的浮游真核微型生物群落结构与理化因子相关系数有所差异。此外, 分别筛选出了1个、8个末端限制性片段代表了潜在的敏感(Cystobasidium sp.或Protostelium nocturnum)、耐污(Acanthamoeba hatchetti、Babesia bicornis、Blastocystis sp.、Botryosphaerella sudetica、Candida caryicola、Coccomyxa simplex、Cryptomonas ovata、Filos agilis、Stenophora robusta、Sulfonecta uniserialis、Theileria sp.等)物种/类群。