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1.
长白山自然保护区夜蛾科多样性研究初报   总被引:2,自引:0,他引:2  
2003年6月至2005年9月,对长白山国家级自然保护区的北坡、西坡和南坡的夜蛾科昆虫做了较全面的调查,共获得标本1 512只,有100属182种,其中绿组夜蛾Anaplectoides prasina(Denis et Schiffermüller)是保护区内夜蛾科的优势种,且各林带均有分布,而各林带均有分布的种只有8种.在不同生境中,夜蛾科多样性随海拔的升高夜蛾的多样性有较明显的变化,其中红松阔叶林带夜蛾科昆虫的物种丰富度、个体数量和多样性指数最高,针叶林带物种丰富度和个体数量最低,苔原带多样性指数最低.不同林带间的夜蛾相似性系数很低.  相似文献   

2.
长白山北坡访花昆虫研究(Ⅲ)——访花昆虫多样性   总被引:2,自引:0,他引:2  
2004—2005年6—9月对长白山北坡各垂直带访花昆虫进行了系统调查研究,并用各种多样性指数对访花昆虫的多样性进行了测度.研究结果表明,该区访花昆虫有251种,分别隶属于9目、62科、179属.群落的α多样性分析表明,不同群落多样性指数从高到低的变化顺序是:针阔混交林群落>针叶林群落>岳桦林群落>苔原带群落;不同月份多样性指数从高到低的变化顺序是:7月末>7月中旬>6月末>6月中旬>8月中旬>9月初;在4个不同群落中,针阔混交林群落访花昆虫的物种数、个体数、物种多样性指数及物种均匀度指数均高于其他群落;群落的相似性分析和聚类分析表明,各不同群落访花昆虫之间的相似性差异显著,访花昆虫群落多样性变化主要与植被类型有关.  相似文献   

3.
2015年5—9月,通过对河北雾灵山国家级自然保护区7个样点进行森林昆虫多样性普查,初步鉴定得到蛾类昆虫23科436种.针对该结果,使用Simpson多样性指数、Shannon-Wiener多样性指数、Pielou均匀度指数、Whittaker多样性指数和Margalef丰富度指数对其中分布较广的11科进行群落多样性分析,结果发现:雾灵山不同生境下蛾类昆虫多样性由大到小依次为针阔混交林带、农田带、寒温性针叶林带;不同海拔条件下物种多样性大小顺序为1 000~1 500m、500m以下、500~1 000m、1 500m以上;不同月份的物种多样性大小顺序为7月、8月、6月和5月.通过对五岔沟不同月份的物种多样性进行单独分析,发现该样点物种多样性情况与保护区整体不同,多样性大小顺序为7月、6月、8月.对不同的环境因素进行β多样性分析,发现蛾类昆虫的多样性受生境影响最大.综上,雾灵山蛾类昆虫的物种多样性和均匀度在各因素下差别不大,表明保护区整体环境良好,受人为干扰影响较小.  相似文献   

4.
长白山自然保护区蝴蝶多样性研究   总被引:4,自引:0,他引:4  
2003~2006年对长白山保护区蝴蝶种类进行了调查研究,共采集蝴蝶121种,隶属7科63属,以蛱蝶科为主要科,各林带均有分布共有19种.在不同生境中,随着海拔的升高蝴蝶的多样性有较明显的变化,其中红松阔叶林带蝴蝶的物种数、多样性指数、均匀度最高,苔原带最低.  相似文献   

5.
对陕西子午岭国家级自然保护区鳞翅目昆虫蝶类资源调查,共记录蝴蝶1 926只,隶属于6科34属47种,蛱蝶科种类最多,有13属18种,其次为粉蝶科6属11种,弄蝶科种类最少,有2属3种。在选取的林地、灌丛、湿地、草地和农田5种生境中,林地蝶类物种数量、多样性指数、均匀度及丰富度指数均最高,原因为林地植被类型多,人为干扰小,故恢复植被是提升蝶类资源丰富度的重要手段;蝶类群落结构及多样性随季节的变化而变化,各月份蝶类多样性指数和丰富度指数变化基本一致,从5月份到7月份逐渐递增,到8月份开始下降,9月份达到最低,蝶类种类和数量最多集中在6月、7月和8月。  相似文献   

6.
野鸭湖湿地自然保护区地表昆虫多样性分析   总被引:2,自引:0,他引:2  
通过巴氏罐诱法对野鸭湖湿地自然保护区段的妫水河南岸的不同生境进行了地表昆虫多样性调查,采集昆虫标本2459头,共有7目25科,其中膜翅目(38.2%)和鞘翅目(30.4%)数量较多,膜翅目中数量最多的是蚁科,鞘翅目中数量最多的是步甲科;在科级水平上,样带Ⅲ的地表昆虫多样性指数最高(1.802),均匀度也最高(0.612),样带Ⅱ的丰富度最高(2.845);所调查的地表昆虫在四个不同的样带中的数量分布差异不显著(P=0.115).植被多样性影响地表昆虫的整体分布.不同地表昆虫类群对生境表现出不同的分布倾向.  相似文献   

7.
在鉴定昆虫标本16目157科1979种54795号的基础上,对河北省8个自然保护区(林场)昆虫物种多样性进行了比较.结果表明,各样地的昆虫物种丰富度较高,生态环境和植物群落发育良好,昆虫群落处于较稳定的状态;各样地间的昆虫物种多样性差异较大,以雾灵山的昆虫物种多样性最为丰富;昆虫群落的物种构成与样地间的相互位置关系密切,地理位置越近,物种组成也越相似;昆虫群落的物种多样性受自然环境条件影响和人为活动干扰均较大.  相似文献   

8.
为了调查重庆大巴山国家级自然保护区蚂蚁物种多样性,作者通过样地调查法对大巴山自然保护区2个主要流域、6个垂直带、9个水平带、33块样地蚂蚁群落进行调查,分析不同样地间蚂蚁群落物种组成、个体数目、群落多样性、优势度与群落相似性等特征.结果表明,在大巴山自然保护区共发现蚁科昆虫5亚科32属59种,其中24种为重庆新记录种.多样性分析表明,各样地蚂蚁群落个体丰富度为38~6 815头;物种丰富度为3~19种,Shannon–Wiener多样性指数为0.184 1~2.127 5,Simpson优势度指数为0.144 0~0.928 0,Pielou均匀度指数0.167 6~0.850 3.前河下段海拔1 000 m低山偏暖性山地阔叶林物种最丰富(19种),前河中段海拔1 000 m低山偏暖性山地阔叶林多样性指数最高(2.127 5),优势度指数最低(0.144 0),前河上段海拔2 000 m亚高山偏寒性针叶林均匀度最高(0.850 3).物种丰富度以前河较高,任河较低.群落相似性系数显示不同海拔与植被的蚂蚁群落物种组成差异显著.整体看来,大巴山蚂蚁群落的个体数目呈现随海拔上升而递减的规律,物种数目、多样性指数、优势度指数与群落相似性随海拔上升普遍呈先增加后降低的单峰模式,与低海拔地带受人为干扰导致的植被次生化和碎片化有关.海拔、植被和人为干扰均对蚂蚁物种多样性有重要影响.  相似文献   

9.
2015年5-8月对河北省辽河源自然保护区灯下蛾类及主要种类的发生情况进行了调查,获得标本21科417种1539头.其季节发生情况是:尺蛾科在整个调查期内处于优势;灯蛾科为5月份优势种;夜蛾科为6、8月份优势种;尺蛾科在7月份发生数量较大.结果显示,该保护区蛾类发生以5月最低,7月最高,各月份间差距不大;该保护区的蛾类群落多样性指数与均匀度不一致,群落的种—多度关系接近于对数正态分布模型,说明该保护区的生态环境良好.  相似文献   

10.
苔原是冷湿型极地自然景观类型,全世界现代苔原仅分布于北半球.综述北极苔原带昆虫的物种组成:部分苔原带种类存在较明显的形态适应,北极苔原带温度和紫外线对昆虫有较大影响,较低温度和较短的生长季节是导致昆虫多样性较低和形态变化的主要原因,当温度升高时昆虫能快速扩散到北极苔原带;综述长白山苔原带昆虫种类组成,侵入种及侵入原因,直翅目蝗虫种群适应变化和天牛、食蚜蝇、蝶类访花昆虫种类及其访花习性等研究进展.  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.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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