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1.
洛河中游河岸带不同生境类型中物种多样性研究   总被引:1,自引:0,他引:1  
为研究河岸带植被不同生境类型中物种多样性变化格局,在洛河中游沿河岸带通过样地调查,采用Patrick丰富度指数(R)、McIntosh均匀度指数(E)、Simpson优势度指数(C)、Shannon-Wiener多样性指数(H)、Simpson多样性指数(D)对洛河中游河岸带不同生境类型(河滩、农田、撂荒地和林地)草本层的物种多样性进行评价,利用重要值对多样性指数中的Ni进行无偏估计.结果表明:洛河中游河岸带植物种类丰富,有33科,97属,141种,分布最多的为菊科,其次是禾本科.沿洛河河岸带不同生境类型中,物种多样性各项指标有一个明显的变化格局:丰富度指数中,河滩>林地>撂荒地>农田;多样性指数(Shannon-Wiener多样性指数和Simpson多样性指数)中,河滩>林地≈撂荒地>农田;农田均匀度最高,且优势度也最高.  相似文献   

2.
莫莫格国家自然保护区昆虫多样性研究   总被引:1,自引:0,他引:1  
对莫莫格国家级自然保护区的昆虫进行了系统调查,采用Shannon-Wiener多样性指数(H')、Simpson优势度集中性指数(D)、Pielou均匀度指数(J')及PIE种间相遇率对不同生境优势目昆虫进行了比较分析.结果表明:应用4种多样性指数测度6个优势目昆虫总体多样性时,其结果虽有差别,但都显示碱蓬群落的多样性...  相似文献   

3.
为了解天津滨海国际机场地被昆虫的多样性特征从而有效防控该地区的鸟类撞机事件,分别于2014年和2015年的4—9月份,对该地区3个样地的地被昆虫进行了连续调查,并利用昆虫群落优势度、丰富度、均匀度和多样性等指标对不同区域的地被昆虫进行测度和分析.结果表明:(1)在天津滨海国际机场这一特定生境共采集到9目22科的昆虫种群,其中鳞翅目、鞘翅目和蜻蜓目等为优势类群;(2)在紧邻机场边界且靠近农田与村庄的六号泵站附近和有丰富水源的西跑道南航向地被区,昆虫多样性指数高于周围有建筑群和垃圾堆放的七号泵站附近地被区,七号泵站附近地被区的物种丰富度最高,西跑道南航向地被区次之,六号泵站附近地被区最低;(3)各生境区域昆虫群落的均匀度指数与多样性指数季节变化趋势相同,优势度指数特征排列顺序为:六号泵站附近地被区七号泵站附近地被区西跑道南航向地被区;(4)3种生境中的昆虫相似性系数都较高,反映出各生境类型中昆虫栖息地空间的异质性较小.  相似文献   

4.
武夷山自然保护区跳甲亚科昆虫物种多样性研究   总被引:1,自引:0,他引:1  
1996 - 1997年 ,在武夷山自然保护区设置了五个样点 ,对跳甲亚科 (Alticinae)昆虫的多样性进行了研究。采用 Margalef丰富度指数 (DMA)、Shannon- Wiener信息多样性指数 (H′)、Pielou的均匀度指数 (Jsw) ,计算群落的丰富度、多样性、均匀度。结果表明 ,不同样点、不同月份、不同海拔高度 ,跳甲亚科 (Alticinae)昆虫群落的物种数 (S)、丰富度指数 (DMA)、多样性指数值 (H′)、均匀度值 (Jsw)均有明显差异。  相似文献   

5.
基于长治市浊漳河南源湿地植物群落的野外调查,运用TWINSPAN和生境分类法对样方进行分类,并运用Patrick丰富度指数(R)、Shannon-Wiener多样性指数(H′)、Simpson多样性指数(D)和Shannon均匀度指数(J′)进行多样性研究。结果表明:(1)Patrick丰富度指数(R)、Shannon-Wiener多样性指数(H′)、Simpson多样性指数(D)和Shannon均匀度指数(J′)能很好地反映各群丛和不同生境下群落的多样性变化规律。(2)TWINSPAN分类和生境分类得到的群落多样性变化趋势是一致的,即湿生植物群落沼生植物群落=中生植物群落水生植物群落。(3)生境异质性和物种的生态学特性对植物群落的分布、物种组成及其群落多样性和均匀度具有显著的影响。  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.
元谋干热河谷不同森林群落蝽类多样性   总被引:3,自引:0,他引:3  
采用样地调查法对云南元谋干热河谷7种森林群落的蝽类昆虫进行研究,共采获蝽类昆虫标本928号,计45种.云南松人工林和印楝人工林的蝽类物种丰富度、Shannon-Wiener多样性指数及Pielou均匀度指数最高.Simpson优势度最低;而牛筋条-黄荆林物种丰富度低、Shannon-Wiener多样性及Pieiou均匀度指数最低,Simpson优势度最高.Jaecard指数显示7种森林群落蝽类之间为不相似水平,体现了各群落的蝽类多样性,是维护元谋干热河谷生物多样性的资源.  相似文献   

8.
太宽河自然保护区栓皮栎群落物种多样性研究   总被引:1,自引:0,他引:1  
在野外调查基础上,采用TWINSPAN将山西太宽河自然保护区栓皮栎群落分为8个群丛,然后分别用丰富度指数、均匀度指数和物种多样性指数对栓皮栎群落的物种多样性进行研究,并用方差分析对各群落之间多样性指数的差异程度进行分析.结果表明:1)栓皮栎群落的物种丰富度指数主要受灌木层影响,然而不同层次的物种对群落物种多样性的贡献不同;2)由于相似的适应特征、物种相似的生境条件和资源利用方式,因此8个群丛各多样性指数间差异不显著(P>0.05);3)在坡度比较平缓、土层较厚和水分条件较好的生境中,栓皮栎群落具有较高的多样性指数;在干扰较强、贫瘠的生境中,多样性指数则较低.  相似文献   

9.
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   

10.
历山白云洞景区植物群落物种多样性研究   总被引:2,自引:0,他引:2  
采用TWINSPAN将历山白云洞景区植物群落分为8个群丛,应用丰富度指数、多样性指数和均匀度指数对不同群落类型和层片的物种多样性进行了研究.结果表明:(1)Shannon-Wiener多样性指数与均匀度指数变化趋势整体相似,与丰富度指数变化趋势略有差别,与Simpson多样性指数变化趋势相反,三种多样性指数取得了较一致的分析结果.(2)不同层次的物种对群丛的物种多样性贡献是不等价的,群丛的丰富度指数主要取决于灌木层和草本层,而多样性指数和均匀度指数主要取决于灌木层和乔木层.  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.
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   

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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