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1.
采用样方、样线相结合的方法,对大连市主城区南部山体维管束植物多样性进行了系统的调查,结果显示大连市主城区南部山体区域内常见植物47科102属141种.对植物群落的不同类型、不同层次的丰富度和均匀度以及物种多样性进行分析,并且对各山体不同坡向的植物物种组成进行Jaccard指数计算.结果表明:①群落各层次与多样性指数的关系表现:丰富度指数排序为草本层灌木层乔木层;物种多样性指数排序主要表现为草本层灌木层乔木层;均匀度指数表现为人工林中乔木层较低,自然群落中乔木层较高,灌木层和草本层的各群落之间则差异不大.②各山体不同坡向的相似性指数存在差异且均0.5,综合坡度等因素,证明大连主城区南部山体植物的组成与坡向间存在关联性.  相似文献   

2.
采用样方、样线相结合的方法,对步云山进行了森林植物群落调查.共记录植物79科226属379种,其中,被子植物66科210属352种,裸子植物1科1属1种,蕨类植物12科15属26种.对群落分类、物种多样性及物种多样性与海拔因子的关系进行了分析,结果表明:(1)步云山共划分为13个森林群落类型;(2)步云山各植物群落的丰富度指数和Simpson指数整体呈现草本层乔木层灌木层,而均匀度指数则整体呈灌木层乔木层草本层;(3)步云山各植物群落的乔木层丰富度指数、Simpson指数、ShannonWiener指数和均匀度指数随海拔的升高均呈先上升后下降的趋势,而灌木层和草本层的物种多样性指数随海拔的升高均呈先下降后上升的趋势.  相似文献   

3.
太湖西区公路两侧植物物种多样性的研究   总被引:6,自引:1,他引:6  
按植物群落的乔木层、灌木层、草本层和藤本层,运用物种丰富度指数(S)、Shannon-Wiener指数、Simpson指数和Pielou均匀度指数,研究无锡马山国家旅游度假区公路两侧主要植物群落的物种多样性。结果表明:(1)各植物群落乔木层和灌木层的4种生物多样性指数变化具有相关一致性,草本层则差异较大;(2)公路边坡经人工植被修复后,植物物种多样性比未经修复的显著增加,起到防护边坡和改善景观的作用;(3)修复的湖滩地植物群落盖度大,但种类单一,故物种多样性较低;(4)原生植物群落的物种多样性最大;合理的人工修复可促进受损植物群落生物多样性增加;(5)通过物种多样性计算方法的比较,可以更客观地反映一个地区的物种多样性状况。  相似文献   

4.
采用样方调查法对临沂蒙山国家森林公园龟蒙顶植物群落物种多样性及群落特征进行研究。结果表明,4个样方(共1 600 m2)中,记录到维管植物43种,隶属18科31属。4个群落垂直结构明显,可划分为乔木层、灌木层和草本层,主要物种分别为栓皮栎、荆条和鸭跖草。从物种多样性指数的平均值来看,物种丰富度(S)、多样性(H′)、均匀度(E)和优势度(D)基本表现由大到小的顺序为草本层、灌木层、乔木层。但4个样方相同层次的物种多样性有一定差异。建议重点保护植物优势物种,同时加强群落物种多样性的发展,促进蒙山国家森林公园龟蒙顶植物群落发挥生态功能。  相似文献   

5.
河南小秦岭自然保护区天然混交林物种多样性研究   总被引:1,自引:0,他引:1  
应用物种丰富度指数、多样性指数和均匀度指数等指标对小秦岭国家级自然保护区西枣香林区1 hm固定样地内的植物区系组成和物种多样性进行研究分析.结果表明,样地内共有胸径≥1 cm的木本植物54种3514株,隶属于28科41属;区系成分较为复杂,以广布分布成分为主,同时含有一定比例的温带和热带区系分布,体现了该区南北过渡,东西交汇的特征.群落各层次的Shannon—Wiener多样性指数(H)表现为乔木层>灌木层>层间植物层;Hurlbert指数(DH)表现为乔木层>灌木层>层间植物层;Margalef丰富度指数(D2)表现为乔木层>灌木层>层间植物层;Pielou均匀度指数(J)表现为乔木层>灌木层>层间植物层;Simpson优势度指数(D1)表现为层间植物层>灌木层>乔木层.为认识和研究小秦岭物种多样性特点提供参考.  相似文献   

6.
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   

7.
南宁市园林滨水绿地植物多样性调查分析   总被引:4,自引:0,他引:4       下载免费PDF全文
采用样方调查方法,通过Margalef指数、Shannon-Wiener指数和Pielou指数分析南宁市9个园林滨水绿地植物群落物种丰富度、多样性及均匀度。结果表明:在100个样方共记录植物176种,其中乔木46种,灌木60种,草本70种;从整体来看,植物Margalef指数与Shannon-Wiener指数均表现为灌木层草本层乔木层,而Pielou指数则与前两者不同,表现为灌木层乔木层草本层;从不同类型的园林滨水绿地比较,各个指数的表现不尽相同;乔木层、灌木层、草本层的Margalef指数最大值(6.488、13.510、8.630)均出现在南湖公园,乔木层和灌木层Shannon-Wiener指数最大值(2.886、3.873)出现在南湖公园,草本层Shannon-Wiener指数最大值(2.236)出现在狮山公园;乔木层和草本层Pielou指数最高的是民生广场(0.906、0.970),灌木层Pielou指数最高的是狮山公园(0.847);Margalef指数和Shannon-Wiener指数高的植物群落物种丰富,群落结构较为复杂,生态功能较好;Pielou指数较低的群落植物造景手法多变、景观异质性高。  相似文献   

8.
荆州城市公园植物群落多样性研究   总被引:1,自引:0,他引:1  
目的分析荆州城市公园植物群落物种多样性,为荆州及周边地区城市公园绿地规划和植物多样性保护提供参考依据.方法采用典型样方法,对荆州市7个城市公园选取235个样方开展植物多样性现状调查,分析其群落特征.结果荆州城市公园植物物种丰富,共有植物96科248属351种,植物群落优势种明显,植物多样性总体趋势依次为:灌木层,乔木层,草本层,但各公园之间又有差异,以中山公园和荆襄河湿地公园为最高;植物多样性指数大小依次为:综合公园,带状公园,专类公园.结论荆州城市公园植物群落物种组成较为丰富,物种多样性较高,但专类公园植物单一性较高,故选择适宜的植物品种,增加乡土植物的运用,提高群落的稳定性.  相似文献   

9.
七星公园植物多样性调查研究   总被引:1,自引:0,他引:1  
为了解植物区域化分布特点及多样性,分别应用物种丰富度指数(S)、多样性指数(Shannon-Wiener指数)、优势度指数(Simpson指数)和均匀度指数(E)对七星公园植物群落进行了研究.结果表明:样方内植物乔木有9种,灌木7种,草本4种.表现出的丰富度指数为灌木层〉乔木层〉草本层;Shannon-Wiener指数为乔木层〉灌木层〉草本层;Simpson指数为乔木层〉草本层〉灌木层;Pielou均匀度指数为草本层〉乔木层〉灌木层.  相似文献   

10.
龙蟠河公园有47科72属101种园林植物。植物群落结构表现出的Margalef物种丰富度指数为灌木层乔木层草本层;多样性指数(Shannon-Wiener指数)为灌木层乔木层草本层;Pielou均匀度指数为灌木层乔木层草本层。建议在构建植物群落多样性时,优选乡土树种和具有明显地域特色的植物。  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.
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   

18.
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   

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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