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1.
赣江中下游浮游动物时空分布特征及水质综合评价   总被引:1,自引:0,他引:1       下载免费PDF全文
对2010年12月与2011年7月赣江中下游各监测断面中浮游动物类群的结构组成、优势类群进行调查,结果表明:赣江中下游浮游动物有4类41种;种类最多的是轮虫类,共计7科15属25种,占总数的60.98%;枝角类5科6属7种,占17.07%;桡足类与原生动物占21.95%。时间分布上浮游动物丰度丰水期大于枯水期,密度变动范围为100~522个/L,其中丰水期轮虫、枝角类、桡足类与原生动物密度分别占浮游动物密度的61.7%,11.4%,18.9%与7.8%;枯水期轮虫、枝角类、桡足类与原生动物密度分别占浮游动物密度的65.3%,9.5%,16.0%与9.1%。浮游动物密度空间分布上呈现中间大、两端小的特点,最大值出现在4号监测点新干,最小值出现在10号监测点赣州。赣江中下游浮游动物数量结构主要由轮虫和桡足类组成,生物量结构则主要由桡足类和枝角类组成。生物多样性及水质综合评价为轻度污染至中度污染。  相似文献   

2.
东苕溪夏季浮游动物群落结构及水环境的初步研究   总被引:1,自引:0,他引:1  
2013年7月对东苕溪(太湖主要入湖河流)的浮游动物群落结构及相关环境因子进行了水生态调查.结果表明,共采集浮游动物41种,其中轮虫23种,桡足类11种,枝角类7种.卜氏晶囊轮虫(Asplanchn.brightwelli)、长三肢轮虫(Filinia.longiseta)、针簇多肢轮虫(Polyarthra.trigla)为优势种.浮游动物的丰度以轮虫占优势,浮游动物的生物量以枝角类和桡足类占优势,东苕溪水系浮游动物的丰度和生物量范围分别为1.99~1964.42ind/L和0.05~8.15mg/L.Shannon-wiener多样性指数(H)为0.10~3.35;Pielou均匀度指数(J)为0.06~0.86,根据浮游生物物种多样性指数评价表明,东苕溪水系处于轻度污染、β-中度污染水平.相关性分析表明,夏季浮游动物群落结构与水体中的总氮、总磷和叶绿素有显著的影响.浮游动物种类数与叶绿素a含量有显著的正相关,浮游动物生物量与总氮、总磷含量有显著正相关.  相似文献   

3.
于2010年3月-2011年2月对福建省九龙江江东库区的浮游动物进行了生态调查研究.研究结果表明,调查期间共采集到浮游动物99种,其中原生动物20种,轮虫29种,枝角类39种,桡足类11种.浮游动物丰度年均为5 486.73L-1,浮游动物的丰度主要由原生动物和轮虫组成,其中原生动物丰度最高,为4 926.90 L-1,轮虫为552.91L-1,枝角类为5.13 L-1,桡足类丰度最低,年均为1.79 L-1.浮游动物丰度最高值出现在11月,最低值出现在3月.温度是影响浮游动物群落的主要影响因子,轮虫和桡足类丰度分别与叶绿素a(Chl a)浓度存在显著正相关性.挖沙船的频繁活动可能促进了原生动物的生长,降低了浮游动物群落丰富度.短滞留时间和鱼类的捕食压力是造成枝角类和桡足类丰度低下的主要原因.  相似文献   

4.
上海滴水湖浮游动物研究初报   总被引:6,自引:0,他引:6       下载免费PDF全文
在2006年2月~2007年2月对滴水湖进行调查采样,研究了该湖泊中的浮游动物群落结构及其季节变化.通过调查共鉴定浮游动物39种:轮虫27种,桡足类10种,枝角类2种.优势种有中华窄腹剑水蚤(Limnoithona sinensis)、褶皱臂尾轮虫(Brachionusrotundiformis complex)、中型六腕轮虫(Hexarthra intermedia)、角突臂尾轮虫(Brachionus angularis)和疣毛轮虫(Synchaetasp.),不同季节浮游动物优势种类不同.浮游动物生物量7月份最高,2月份最低.  相似文献   

5.
2016年4月—2017年3月,每月对丽水市黄村水库流域浮游动物(包括轮虫、桡足类和枝角类)进行了调查,分析其群落结构的生态特征、水库与河道中群落时空分布差异性及其关键影响因子.结果显示:该水域共检出浮游动物37种,其中轮虫27种,桡足类5种,枝角类5种.基于浮游动物群落数据进行聚类分析,将所调查的水体区域分为4类:上游河道、大洋水库、(两水库间的)连接河道和黄村水库.4类区域的浮游动物群落在种类、多样性、优势种、生物量及特有种方面特征明显.黄村水库、大洋水库和连接河道均从上游河道处来水,但浮游动物群落结构却出现不同程度的差异性,表明浮游动物群落的构建过程与环境(局域物种分选过程)和空间(扩散限制)有着重要关联.  相似文献   

6.
淀山湖后生浮游动物群落结构特征分析   总被引:2,自引:0,他引:2  
于2008年10月至2009年10月对淀山湖浮游动物的群落结构组成及现存量进行了调查研究.共鉴定浮游动物80种,其中轮虫46种(58%),枝角类21种(26%),桡足类13种(16%),优势种主要为螺形龟甲轮虫(Keratella cochlearis)、矩形龟甲轮虫(Keratella quadrata)、曲腿龟甲轮...  相似文献   

7.
对乌江上游11个水库24个点进行4次采样,在样品分析中共记录到浮游硅藻77种,隶属于2纲7目9科21属;浮游动物71种,其中轮虫10属25种,占总种数的35.21%;枝角类10属23种,总种数的32.39%;桡足类11属23种,占总种数的32.39%。调查结果显示乌江上游各湖泊水库的浮游硅藻及浮游动物的群落多样性低,特别是乌江渡水库及偏岩河河段,在2008年4月份以华丽星杆藻(Asterionella formosaHassall)为主酱油色的水体,为轻度硅藻水华,浮游硅藻及浮游动物的多样性最低。各水库中的浮游硅藻主要优势种为小环藻属(Cy-clotollakutzing)、尖针杆藻(Syneder acuskuetzing),华丽星杆藻(Asterionella formosaHassall),并呈季节性的交替变化;浮游动物主要是轮虫(Keratella cochlearisGosse)密度变化最为明显,枝角类(Cladocera)、桡足类(Copepo-da)变化不明显。  相似文献   

8.
为了解城市景观河流浮游动物群落结构以及水生态环境状况,于2018年对渭河关中段4个城市景观河流开展季节性采样.共计鉴定出浮游动物78种,其中轮虫46种,枝角类和桡足类分别为14和18种.全年浮游动物总密度介于0.452~7.482×103 ind./L,轮虫密度占总密度的83.51%.全年浮游动物总生物量介于0.207~6.834 mg/L,以枝角类、桡足类为主,占总生物量的74.05%.全年浮游动物优势种属17个,萼花臂尾轮虫(Brachionus calyciflorus)、蒲达臂尾轮虫(Branchionus budapestiensis)、针簇多肢轮虫(Polyarthra trigla)、矩形龟甲轮虫(Keratella quadrata)等优势度较高,优势种多为中污染或富营养水体的指示种.Shannon-Wiener多样性指数(H′)春、夏、秋、冬季均值为2.27,2.72,2.06,2.13;Margalef丰富度指数(d)均值分别为0.990,0.069,0.020,0.830;Pielou均匀度指数(J)均值分别为0.32,0.02,0.01,0...  相似文献   

9.
为了研究枝角类和桡足类的物种组成与分布以及与水环境因子的相关性,于2018年8月对白洋淀枝角类和桡足类及水环境因子进行了调查.基于DNA条形码技术对白洋淀的枝角类和桡足类种类进行鉴定,建立系统发育树,通过系统发育树鉴定物种种类并表明其遗传距离,共鉴定出枝角类3科5属8种,桡足类4科9属14种.采用典型相关分析(CCA)方法分析枝角类和桡足类与水环境因子相关性.结果表明:Zn含量是枝角类和桡足类区域性分布差异的主要原因,枝角类种类数量及群落组成与P含量呈负相关,每个物种的生长都受不同水环境因子影响,相同水环境因子对于不同物种的分布影响也存在差异.  相似文献   

10.
上海青草沙水库后生浮游动物群落结构   总被引:4,自引:0,他引:4  
于2010年7月~2011年6月对上海市青草沙水库浮游动物的种类组成、生物量进行了周年的调查和分析,共鉴定浮游动物38种,其中轮虫16种,枝角类9种,桡足类13种,优势种为矩形龟甲轮虫Keratella quadrata、长额象鼻溞Bosmina longirostris、广布中剑水蚤Mesocyclops leuckarti和中华哲水蚤Sinocalanus sinensis.浮游动物各样点平均密度变化范围为8.46~97.71ind./L,平均生物量为0.284~19.470mg/L.结合分层聚类(Cluster analysis)和多维尺度分析(MDS)的结果,青草沙各样点被分为4组;通过主要环境因子相关性分析可知,pH值、总氮与青草沙水库浮游动物的密度呈显著相关,其他环境因子对浮游动物密度影响不显著.生物多样性指数评价表明,库区水质属于中度污染,结合浮游动物种类组成和群落结构进行综合评价,提示库区浮游动物群落结构趋于简单,水体环境稳定性有所下降,相关部门需要加强预控和防范管理.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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