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1.
两次对邻水县的两栖爬行类进行了调查,结果表明:邻水县有两栖动物15种(隶属2目7科8属),爬行动物21种(隶属2目8科15属)。动物地理分布型为:热带亚热带型6种,占16.7%;全北型1种,占2.8%;南中国型19种,占52.8%;季风型8种,占22.2%;喜马拉雅-横断山型2种,占5.56%。区系组成:属东洋界有:华中区物种17种,占47.2%,华中华南区物种6种,占16.7%,东洋界广布种4种,占11.1%,属东洋、古北两界广布种的有9种,占总物种数的25%。  相似文献   

2.
【目的】调查重庆市城口县双翅目(Diptera)食蚜蝇科(Syrphidae)昆虫的种类并进行区系分析。【方法】在城口县所辖全部25个乡(镇、街道)内用样线法、灯诱法、马来氏网法等系统地开展了食蚜蝇科昆虫调查;对所有标本开展了形态学鉴定和物种描述;编制了分种检索表,并进行了区系分析。【结果】采集和检视了城口县食蚜蝇科的昆虫标本共400余头;经鉴定,它们分属2亚科、6族、10属、13种,其中3族、6属、9种为城口县新纪录族、属、种。城口县的食蚜蝇科昆虫具有东洋界和古北界的成分,但以东洋界的成分占主体;而它们在中国动物地理区系中具有9种不同的物种区系分布型,所有记述的种类都分布于东洋界的华中区和古北界的华北区。【结论】研究结果有助于城口县食蚜蝇科昆虫的正确鉴定、保护和利用。  相似文献   

3.
三峡库区巫山县五里坡自然保护区鸟类区系分析   总被引:1,自引:0,他引:1  
1996-2006年调查资料表明,重庆市巫山县五里坡自然保护区截至目前为止记录有鸟类294种,隶属于17目51科,其中列入国家Ⅰ级保护动物的鸟类有2种,国家Ⅱ级保护动物的鸟类有35种,共计占鸟类物种总数的12.59%.仅分布于中国的鸟类有11种,主要分布于中国的鸟类物种有2种,特有种分布占鸟类物种总数的4.42%.从属区系为:古北界110种;东洋界113种;广布种71种;不同从属区系物种分别占库区鸟类物种总数的比例为:古北界37.41%,东洋界38.44%,广布种24.15%.如果仅考虑繁殖鸟类226种的从属区系为:古北界58种,东洋界110种,广布种58种;不同从属区系物种分别占库区繁殖鸟类物种总数的比例为:古北界25.66%,东洋界48.67%,广布种25.66%.在划分的7个鸟类生境中,与灌草丛和森林这2种生境相关的鸟类物种数和适应值最高.  相似文献   

4.
研究记录了三清山两栖纲动物2目7科24种,是江西省两栖纲动物比较丰富的地区之一.研究结果表明,小棘蛙、九龙棘蛙是江西省的新纪录,无斑肥螈在江西省的分布得到了证实,树蛙科、姬蛙科和蛙科种类颇为丰富.棘胸蛙组3种均分布于三清山;黑斑侧褶蛙、泽蛙、花臭蛙、棘胸蛙和中华大蟾蜍为优势种群;垂直分布特点明显,低海拔物种数量较多,随海拔升高,物种数量减少.中国特有动物13种;虎纹蛙为中国国家Ⅱ级重点保护动物;中国物种红色名录易危(VU)物种4种,近危(NT)物种1种.区系组成上东洋界成分占据绝对优势,东洋界成分仅由华中区成分及华中华南区共有成分组成,没有华南区成分.华中区成分和本区中国特有种均属南中国型.南中国型在该区出现频率高达58.3%,表明该区仍为其优势分布区.  相似文献   

5.
通过样线采集法和枯枝落叶筛选法采集广西崇左白头叶猴自然保护区的蚁科昆虫标本,经鉴定共8亚科52属98种,其中广西新纪录种4种。区系分析结果表明:广西崇左白头叶猴自然保护区的蚁科昆虫区系具有典型的东洋界特征;在跨界分布型中,"东洋界+古北界"分布型所占比例最大,说明该保护区的蚂蚁区系与古北界关系最密切;在中国动物地理区系划分中,保护区的蚂蚁区系具有典型的华南区特征;在跨区分布型中,"华南区+西南区+华中区"分布型所占比例最大,说明该保护区的蚂蚁区系与华中区和西南区的关系密切。  相似文献   

6.
为了解世界塔叶蝉物种的多样性、区系成分和分布状况,并探究该类昆虫的起源与演化路径,依据世界塔叶蝉的地理分布数据,研究其区系组成特点,并运用Arc GIS 10.2软件进行栅格分析.结果表明:截至目前,全世界共记录塔叶蝉34属163种,以零叶蝉属为优势类群,全世界有零叶蝉44种,占世界塔叶蝉总数的26.99%.在世界动物区划中,塔叶蝉主要分布于东洋界(属级占44.12%,种级占50.31%)和非洲界(属级占38.24%,种级占36.21%),少数属种渗透分布至古北界和澳洲界,新北界和新热带界均为广布种.塔叶蝉的特有属、种极为丰富,特有属28个,占塔叶蝉总属数的82.35%,世界特有种148个,占塔叶蝉总种数的90.81%.塔叶蝉的起源至少可追溯到中生代联合古陆解体之后,东洋界的中国南部和南亚诸岛是塔叶蝉的现代分布和分化中心.  相似文献   

7.
陕西秦岭地区兽类多样性分析   总被引:1,自引:0,他引:1  
陕西秦岭山地是东洋界和古北界的交汇地带,物种多样性较为丰富.有兽类7目28科82属125种,占陕西省兽类总种数的85.0%.兽类区系组成十分复杂:北方分布型有57种,南方分布型有68种,特有种23种.列入国家重点保护名录、中国物种红色名录和CITES附录的物种有54种,占该区总种数的43.2%.这些珍稀、特有动物主要分布在秦岭地区15个自然保护区内.导致众多物种濒危的原因,主要是栖息地变化和人猎杀等.  相似文献   

8.
调查和研究表明,广东省深圳市围岭公园有两栖动物9种5科1目,全部都属于东洋界物种,其中华中区和华南区的共有物种占66.7%,属华南区的物种占33.3%.已知爬行动物15种8科2目.属东洋界物种有14种,其中华南区物种有6种,占总数的40.0%;华中华南区共有种5种,占总数的33.3%;属华中区种有3种,占总数的20.0%.除此外有1种是属广布种.论文还分析了围岭爬行动物的资源保护.  相似文献   

9.
通过对贵州省关岭县66种叶蝉进行区系分析,结果表明:66种关岭叶蝉在世界动物地理区划中有10个区系型,其中以东洋界区系型为主体,种数为31种,所占比例46.97%;其次为东洋界—古北界区系型,种数为23种,占34.85%;按含特定地理区的跨区区系型复计种数和复计比例来看,纯东洋界区系型所占比例最大,其次为含古北界的跨区区系型.66种关岭叶蝉科昆虫在我国动物地理区划中的归属共计20种类型,其中以华中区特有种所占比例最高,计13种,占19.70%;其次为华中区—西南区—华南区种类,计9种,占13.64%.分析结果表明66种关岭叶蝉昆虫在世界动物地理区划中以东洋界为主,在中国动物地理区划中以华中区所占比例最大.  相似文献   

10.
本研究基于GenBank中10个医蛭形亚目物种及2个近缘外类群的基因组或转录组数据,提取COI、18 S和蛋白编码核基因的直系同源序列(Orthologs),开展系统发育分析。比对后的COI、18 S和Orthologs序列长度分别为1533、1832、220095 bp。最大似然法和贝叶斯推断法分析显示,基于Orthologs序列构建的系统发育树在几乎所有节点上的支持率都达到100%,明显优于COI和18 S序列得到的结果。研究表明,医蛭科的欧洲医蛭、东方医蛭和侧纹医蛭组成一个单系群,医蛭科的日本医蛭与黄蛭科的宽体金线蛭和尖细金线蛭组成另一单系群,而黄蛭科的马蛭与上述6个物种形成姐妹群。医蛭科的两种牛蛭(菲牛蛭和棒纹牛蛭)组成一个单系群,此单系群与医蛭科的其他物种的遗传关系比马蛭更疏远;山蛭科的洞穴山蛭在10个医蛭形亚目种类中处于最基部位置。本研究阐明了医蛭形亚目常见物种的系统发育关系,为这些物种的资源开发利用和保护提供科学依据。  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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