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1.
浙江岱山岛潮间带大型底栖动物的群落结构   总被引:4,自引:0,他引:4  
分析了浙江岱山岛潮间带大型底栖动物的种类组成、数量分布和生物多样性等群落结构特征.该海域潮间带调查采获的大型底栖动物标本26种,其中软体动物16种,节肢动物6种,脊索动物2种,腔肠动物与环节动物各1种.潮问带大型底栖动物总平均生物量为279.22g/m2,总平均栖息密度为493 ind/m2.在各类群底栖动物中,平均生物量及密度都以软体动物居首位.岱山岛潮间带大型底栖动物的多样性指数、丰富度指数和均匀度指数的分布范围分别在1.176~2.115、0.833~1.897和0.565~0.801,平均值分别为1.490±0.429、1.223±0.465和0.654±0.104.岱山潮间带大型底栖动物ABC曲线分析表明底栖动物群落中度的污染或者干扰.  相似文献   

2.
为揭示深圳湾福田红树林区小型底栖动物群落的时空变化,在深圳湾福田红树林区3个取样站进行了夏、秋、冬3个季节的定量取样,共发现7个小型底栖动物类群,分别为自由生活海洋线虫、多毛类、寡毛类、双壳类、腹足类、桡足类和昆虫类,还有少许未定类群归为其他类.分析结果显示自由生活海洋线虫是优势类群,它与桡足类的丰度比值高,小型底栖动物的平均丰度为(1 572±389)ind/(10cm2),平均生物量为(814±236)μg/(10cm2).单变量双因素方差分析结果表明:不同取样站和季节的小型底栖动物群落的类群数和丰度无显著差异;小型底栖动物群落的生物量、类群多样性指数、均匀度指数和丰富度指数呈显著的季节变化,但取样站之间无显著差异.综上,深圳湾福田红树林区小型底栖动物优势类群呈现较高的丰度和较低的类群多样性.  相似文献   

3.
深圳湾潮间带底栖动物群落与环境因子的关系   总被引:14,自引:0,他引:14  
对深圳湾底栖动物群落进行了调查。结果表明:①底栖动物群落沿河口到湾内呈连续的梯度变化,盐度可能是造成这一现象的主要原因;②潮汐对底栖动物群落影响并不明显,红树林环境对林底的底栖动物种类组成和丰度有一定的影响;③底栖动物群落在深圳福田一侧与香港一侧没有明显的差别。  相似文献   

4.
[目的]为了解渤海大型底栖动物多样性现状,研究其物种多样性和分类多样性的分布格局。[方法]依据2008年8月和2009年6月两航次渤海大型底栖动物调查资料,对其物种多样性的辛普森优势度指数(λ)、香农-威纳多样性指数(H′)、Margalef物种丰富度指数(d)、Pielou’s均匀度指数(J′)和分类多样性的分类多样性指数(Δ)、平均分类差异指数(Δ~+)、分类差异变异指数(Λ~+)以及各指数与环境因子的关系进行分析。[结果]两航次共鉴定出大型底栖动物(或分类实体)270种,隶属于206属,130科,39目,19纲,12门。各多样性指数平均值λ为0.05,H′为4.80、d为7.35、J′为0.93、Δ为83.84、Δ~+为87.90、Λ~+为343.88。各多样性指数与环境因子中的粉砂-粘土含量、沉积物中值粒径、有机质含量无显著相关性,而水深、盐度和温度等水层环境因子则对其影响较为明显。[结论]渤海海域总体动物多样性较高,其中渤海海域沿岸地区、辽东湾西部、莱州湾西北部等地受扰动和污染严重。将物种多样性和分类多样性结合分析,可以更好地反映群落多样性结构。水深、盐度和温度等水层环境对渤海大型底栖动物的影响要大于沉积环境的影响。  相似文献   

5.
钦州湾秋季大型底栖动物多样性研究   总被引:1,自引:0,他引:1  
利用2008年10月在钦州湾采集的大型底栖动物定量样品,采用大型多元统计分析软件PRIMER,研究该海域大型底栖动物群落的种类组成、密度、生物量和物种多样性情况。结果调查采集到大型底栖动物58种,其中多毛类35种,甲壳动物7种,软体动物10种,棘皮动物2种,其它类群动物4种。底栖动物的群落优势种为蛇杂毛虫(Poecilochaetus serpens)和色斑刺沙蚕(Neanthes maculata),二者累计贡献率达到55.15%。底栖动物的栖息种数、平均生物量和密度以及3个多样性指数的空间分布均形成以S6站为高值中心向周边递减的分布趋势。钦州湾底栖动物群落基本处于稳定状态,但是局部底栖动物群落已受到一定程度的轻微污染扰动。  相似文献   

6.
应用等级聚类与非线性多维标度排序两种多变量统计分析方法研究了深圳湾潮间带底栖动物群落结构的时空变化,结果表明:1)底栖动物群在深圳福田A断面上与香港米博RB和ET断面上有较明显的差异,在A断面高潮区与中、低潮区也有较明显的空间差异。2)RB和ET断面底栖动物群落有明显的季节变化,温度、盐工和潮汐是影响群落结构变化的主要因子。  相似文献   

7.
基于我国沿海12个典型潮间带湿地,结合其生境特征,系统地比较潮间带湿地底栖动物生物多样性特征,在此基础上深入分析不同环境条件下潮间带湿地生境特征与底栖动物群落结构特征之间的关系。结果表明:不同环境条件下潮间带湿地的底栖动物分布表现出典型的空间分异特征,其分界线与潮间带湿地所处位置的自然地理分界线基本一致;在科和属的水平上潮间带湿地群落结构特征与环境变量的关系密切。作为潮间带湿地区别于其他类型湿地的主要特点之一,潮差对潮间带湿地特性有重要影响,潮差与潮间带湿地底栖动物多样性指数呈明显的正相关关系;对于类似环境条件下的潮间带湿地,二者的相关关系尤其显著。  相似文献   

8.
许铭本  姜发军  赖俊翔  张荣灿  雷富 《广西科学》2014,21(4):389-395,402
【目的】研究钦州湾外湾东北部近岸区域大型底栖动物群落结构,判断其受环境干扰的程度,并分析其多样性指数与环境因子之间的相关性。【方法】2010年6月和12月,采用拖网法进行底栖生物样品采集。使用PRIMER和SPSS软件对调查所得数据进行分析。【结果】共采集到大型底栖动物种类148种,其中软体动物57种,节肢动物42种,底栖鱼类20种,其他动物共29种。【结论】调查区域大型底栖动物夏季可划分为3个群落,冬季可划分为2个群落。夏季多样性好于冬季,但冬季各站之间多样性变化范围较小。有少数站位受到中度干扰,个别站位受到稍微干扰。夏季大型底栖动物种类数与悬浮物含量呈显著负相关,生物量、丰度、种类数均与沉积物中的油类含量呈显著负相关,均匀度与沉积物中值粒径呈显著负相关,丰度与沉积物的中值粒径呈显著正相关,Shannon-Wiener指数与沉积物中的粘土含量呈显著正相关;冬季种类数与水体中的盐度、pH值、溶解氧呈显著正相关,与水质中的油类含量呈显著负相关,丰富度指数与溶解氧呈显著正相关。  相似文献   

9.
环境扰动对钦州港潮间带大型底栖动物群落的影响   总被引:5,自引:0,他引:5       下载免费PDF全文
何斌源  邓朝亮  罗砚 《广西科学》2004,11(2):143-147
为了了解钦州港海洋生态环境质量,于2001年春夏两季在钦州港码头区两侧的无名岛和旧营盘,及距离稍远的鸡墩头和鹿耳环的潮间带滩涂,对大型底栖动物状况进行调查。共设置4条断面,每个断面设2~3个站位,用样方方法定量采集动物样品。应用种类相似性指数、生物多样性指数和丰度生物量比较法分析大型底栖动物群落间差异及生态质量状况。结果表明:该海域滩涂潮间带上发现有大型底栖动物70种,包括软体动物贝类38种,甲壳类18种,多毛类5种,鱼类4种,及其他类群的动物5种。生境的相似导致在钦州港码头区两侧的2个断面潮间带动物群落间的相似性最大。在种群水平上,珠带拟蟹守螺(Cerithidea cingulata)为丰度和生物量上的主要优势种。在类群水平上,贝类为主要的优势类群。应用丰度生物量比较法发现码头区两侧的2个断面潮间带动物群落受到扰动,显然是由于环境经常变动导致的。同时,从4个断面的潮间带动物物种数及3个生物多样性指数的比较也得到同样的结论。  相似文献   

10.
黄浦江上游大型底栖动物生物多样性现状   总被引:3,自引:0,他引:3  
2005年4月至2006年3月对黄浦江上游大型底栖动物群落结构进行了调查.采用香农威纳指数(H′)、物种均匀度指数(J)和物种丰富度指数(D)对黄浦江上游大型底栖动物的群落结构、种类组成、多样性进行了分析.本次调查共采到底栖动物13种.密度优势种为环节动物门的霍甫水丝蚓(Limnodrilus hoffmeisteri)、软体动物门的铜锈环棱螺(Bellamya aeruginosa)以及河蚬(Corbicula fluminea).生物量优势种为软体动物门的铜锈环棱螺以及河蚬.淀峰断面的香农威纳指数(H′)、物种均匀度指数(J)和物种丰富度指数(D)都高于松浦大桥.季节变化方面,三种指数的最高值都出现在秋季,最低值则分别出现在夏季、冬季和春季.生物多样性除了受种的数量及其个体密度影响外,还与多种因素有关,如水温、水质、底栖环境和人为干扰等.  相似文献   

11.
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   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

16.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

17.
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   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

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