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1.
根据1990-1992年3年对朋鹏湾进行的赤潮生态研究,分析了大鹏湾浮液植物的季节演替规律。春季甲藻的种类和数量均较多;而硅藻则全年均有分布,且数量较高,对浮游植物优势种群的逐月变化用了研究。  相似文献   

2.
根据1990~1992年3年对大鹏湾进行的赤潮生态研究,分析了大自湾浮游植物的季节演替规律。春季甲藻的种类和效量均较多;而硅藻则全年均有分布,旦数量较高。对浮游植物优势种群的逐月变化作了研究。  相似文献   

3.
大鹏湾有毒赤潮生物孢囊研究   总被引:15,自引:0,他引:15  
自199年至1994年间,对大鹏湾海域9个站位进行了多次采集,对60份样品进行了分析和观察,从其中发现了4种在世界上引起毒害的赤潮生物孢囊,它们是塔马亚历山大藻,海洋褐胞藻、链状裸甲藻、巴哈马梨甲藻,对这种几种有毒赤潮藻类孢囊的形态特征,生态分布进行了描述,对几种毒害藻大鹏湾引发赤潮的可能性进行了预测。  相似文献   

4.
2002年5月-2003年9月对渤海天津海域赤潮监控区进行了网采浮游植物的生态学调查,天津海域共发现浮游植物37属68种,其中硅藻为优势类群,共24属51种,占总种数的75.00%;甲藻7属11种;其他6属6种为少量的蓝藻、黄藻和金藻,其生态类型主要为温带近岸型。圆筛藻属的种类是该海域的全年优势类群,在群落总细胞数中的比例平均高达63.41%。浮游植物群落以大型细胞硅藻.甲藻占优群落为主,其平面分布与环境因子密切相关。  相似文献   

5.
于2006年4月~2007年3月采集浙江南麂列岛海域水样,研究了硅藻和甲藻群落在该海域的种类组成、生态分布特征和季节动态.共鉴定浮游植物93种,其中硅藻35属68种,甲藻11属21种.南麂海域浮游植物细胞丰度较高,年平均细胞丰度达到3.19105cellsL-1.硅藻集群的高峰区主要集中在夏季和秋季,细胞在表层水体的含量高于底层水体,调查期间共记录硅藻赤潮事件1起,发生于2006年8月,优势种类是中肋骨条藻.甲藻赤潮仅在春季(5月)发生,优势种类为原甲藻种类,包括三角棘原甲藻和东海原甲藻,分别在5月中旬和5月下旬先后引发赤潮,甲藻在表层水体含量高于底层水体.  相似文献   

6.
泉州湾虾池浮游植物种类多样性研究   总被引:4,自引:0,他引:4  
2003年11月~2004年5月对福建泉州湾东海虾池进行定点采样,并分析其浮游植物的种类多样性和种群动态.结果表明,泉州湾虾池共有浮游植物42属166种,硅藻为优势种群,共35属154种;甲藻3属6种.新月筒柱藻Cylindrotheca closterium、微小小环藻Cyclotella caspia、狭窄双眉藻Amphora angusta、菱形藻属Nitzschia为主要优势种,它们在浮游植物群落总细胞数中的百分比平均高达34.8%.通过对水温、营养盐、浮游植物种群密度及群落的多样性指数和均匀度的分析,发现虾池高强度的排污排废所引起的富营养化已很大程度影响了浮游植物的群落结构和时空分布,使生物多样性和均匀度下降,少数优势种类大量繁殖.硅藻和甲藻赤潮的发生机会增多.  相似文献   

7.
本文列出了嵊泗列岛养殖海区1990年4月至1991年3月主要生态调查结果。浮游植物密度:0.5m 水层为1.62×10~2——2.51×10~6Cells/L,0—7m 水层为1.8×10~4——3.65×10~8Cells/m~3,八月和十一月出现两次高峰,周年出现浮游植物143种、赤潮生物38种,6—9月是该区赤潮发生季节。此外,还对几种主要赤潮生物的周年变化和发生赤潮时该赤潮生物的衰变特点进行了分析,对两年发生六次赤潮的生物组成、赤潮与赤潮生物密度之间的关系进行了讨论。  相似文献   

8.
深圳沿海浮游植物组成及赤潮发生趋势分析   总被引:7,自引:0,他引:7  
目的 :为了解深圳海域 ,包括深圳湾、大鹏湾和伶仃洋的 9个站位浮游植物的种类组成及数量分布 .方法 :依据国家海洋局制订的《海洋调查规范》进行调查 .结果 :确认深圳海域共有12 5种 (变种、变型 )浮游植物 ,主要为硅藻 ,占浮游植物总量的 90 %以上 ,以角毛藻 (Chaetoceros)、根管藻 (Rhizosolenia)及海链藻 (Thalassiosira)居多 ;甲藻以原甲藻 (Prorocentrum)为多 .浮游植物的水平分布为 :东部以角毛藻为优势种群 ,西部以骨条藻 (Skeletonemacostatun)占优势 .秋末冬初总体上分析浮游植物数量并不算高 .但个别站位如大鹏湾的盐田海域数量高达 17.2× 10 6 /L ;西部的深圳湾也达 11.7× 10 5/L .叶绿素a含量从 1.10mg·m- 3 (S4 站位 )到 2 .34mg·m- 3 (S2 站位 ) .结论 :浮游植物中有约 2 0种为赤潮生物 ,发现有有毒的塔码亚历山大藻 (Alexandriumtamarense)及短裸甲藻(Gymnodiniumbreve) ,应引起高度重视 .  相似文献   

9.
根据1995年3月至1996年1月胶州湾北部水域调查资料,对调查区浮游植物种类组成、细胞数量、优势种组成和季节变化进行了分析研究,并与历史资料进行了比较。结果表明,浮游植物主要由硅、甲藻组成,其中硅藻在细胞数量和种类上都占优势;浮游植物细胞数量平面分布的总趋势依月份而异;季节变化属双周期类型:高峰期出现在1月和9月,低谷期出现于5月和11月;与历史资料不同的是,网采浮游植物的种类和细胞数量都呈现出不同程度的下降趋势。  相似文献   

10.
我国沿海常见浮游植物检索数据库的建立   总被引:1,自引:0,他引:1  
利用本实验室保存的固定和活体硅藻标本,并采集我国沿海常见海洋浮游植物样品,特别是赤潮生物样品,通过数码显微摄影技术,采集不同侧面的藻细胞形态特征图像,同时结合其他手段收集我国沿海常见海洋浮游植物的图片和文字资料.通过net(c#)语言、asp.net等技术初步建立了我国沿海常见浮游植物网络检索数据库,其网络查询界面可实现多分类参数查询.目前该数据库已收录我国常见浮游植物144种,特征图片704张,以硅藻门(93种)和甲藻门(40种)为主.同时对每个种类的分类特征和生态分布特点进行了归类与集成,可通过其细胞主要特征参数或生态分布特征等参数进行详细的信息检索.该数据库为目前国内首个沿海常见浮游植物网络分类数据库.本文简要介绍了建库目标、系统结构、功能与特点,并对该库应用前景作了探讨.  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
20.
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   

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