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1.
Tropical is a software for simulation and parameter estimation of reaction-diffusion models. Based on spatio-temporal microscopy images, Tropical estimates reaction and diffusion coefficients for user-defined models. Tropical allows the investigation of systems with an inhomogeneous distribution of molecules, making it well suited for quantitative analyses of microscopy experiments such as fluorescence recovery after photobleaching (FRAP). AVAILABILITY: Tropical is available free of charge for academic use at http://www.dkfz.de/tbi/projects/modellingAndSimulationOfCelluarSystems/tropical.jsp after signing a material transfer agreement.  相似文献   

2.
对陕西境内木本种子植物区系属一级的热带地理成分进行了研究,全省木本种子植物区系中的热带地理成分共包括泛热带成分、热带亚洲和热带美洲间断成分、旧世界热带成分、热带亚洲至热带大洋洲成分、热带亚洲至热带非洲成分及热带亚洲成分6种类型,共95属,归属于53科。在各种热带地理成分中,陕西木本植物区系与泛热带成分联系最为密切,各类热带地理成分主要分布于陕西秦岭以南地区。从科、属、种的分布区格局以及木本热带区系成分的群落学作用等方面分析,陕西植物区系具有明显的温带性质,同时,区系也呈现一定的热带—温带过渡性特点。  相似文献   

3.
Tropical Environments: The Functioning and Management of Tropical Ecosystems by M. Kellman and R. Tackaberry Routledge, 1997. £60.00 hbk, £18.99 pbk (xix+380 pages) ISBN 0 415 11608 2/0 415 11609 0.  相似文献   

4.
通过对中国38个地区共147属,984种兰科植物的区系成分的统计,分析了各地区兰科植物的属种热带成分/温带成分(R/T)值随纬度的变化趋势;并利用SPSS 20.0软件对各地区兰科植物的区系成分进行聚类分析。结果表明:(1)38个地区147属兰科植物可划分为11种分布区类型和9种变型,984种兰科植物可划分为12种分布区类型和6种变型。(2)属级水平上R/T值随纬度的升高总体呈下降趋势,38个地区中23个地区为热带性质,13个地区为温带性质,峨眉山和金佛山的热带性质和温带性质相等;种级水平上除俄贤岭的特殊岛屿石灰岩环境造成极强的热带性质外,其他地区的R/T值随纬度的升高而降低,表现出明显的纬向地带性特点。(3)38个地区兰科植物属种级区系类型存在分异现象,即147属兰科植物以热带亚洲分布(24.71%)、北温带分布(19.14%)和热带亚洲至热带大洋洲分布(15.32%)为主,而984种兰科植物除热带亚洲分布(30.28%)外,则以中国特有分布(26.89%)和中国-日本分布(12.85%)为主。(4)属种级聚类结果显示,种级水平的聚类分析比属级水平的聚类更能体现出纬度相近其区系成分也相近的特点。  相似文献   

5.
旨在构建适于快速检测橡胶树白粉病菌(Oidium heveae)HO-73启动子的探针载体。以卡那霉素抗性基因Kan作为报告基因,在pUC19骨架载体,构建获得启动子探针载体pUC19-K,连入CaMV35S启动子做启动子探针载体功能验证;利用启动子探针载体pUC19-K对预测的启动子片段LY1、LY2、LY3、LY4进行筛选鉴定。将CaMV35S启动子连入到启动子探针载体中,得到可检测启动子活性的启动子探针载体pUC19-K;应用生物信息学软件对部分橡胶树白粉菌HO-73全基因组数据预测,得到4个理论上具有活性的启动子序列LY1、LY2、LY3、LY4,利用构建的启动子活性探针载体进行活性比较,卡那耐受性实验检测发现含LY2和LY3的菌株随卡那霉素浓度的升高耐受性更强,最终得到2个活性较强的启动子LY2和LY3。以上结果表明,构建的启动子活性探针载体可以有效、灵敏地用于HO-73强启动子的筛选和启动子活性检测。  相似文献   

6.
楝科(Meliaceae)的地理分布   总被引:9,自引:0,他引:9  
楝科为泛热带分布科,全世界有51属,约550—600种,分布于旧世界热带地区有46属,热带美洲有8属.热带亚洲和热带非洲为楝科两大现代分布中心.中国楝科共15属,61种,占世界属总数的29%,种总数的10%。中国楝科的分布是在全球楝科分布区的边缘,主要分布于中国西南部及南部诸省,种类由西南向东南递减。中国楝科属的分布区类型可归为5类:1.热带亚洲、非洲和中南美洲间断分布(1属);2.旧世界热带分布(3属);3,热带亚洲至热带大洋洲分布(2属);4.热带亚洲至热带非洲分布(1属);5.热带亚洲分布(8属)。中国楝科种的分布区类型仅有2类:1.热带亚洲分布(31种);2.中国特有分布(30种)。楝科植物的起源推断在早白垩纪。中国楝科植物由印度—马来西亚成分及特有成分组成。热带亚洲的楝科植物主要是通过中南半岛和中国云南。广西和海南等地发生联系,而菲律宾和台湾之间可有直接的联系。  相似文献   

7.
琼南沿海低山丘陵森林种子植物区系初步分析   总被引:2,自引:1,他引:1  
在对海南岛南端沿海低山丘陵森林植被进行实地调查的基础上,研究了该地区种子植物区系.结果表明:该地区共有野生种子植物112科484属876种(包括变种);植物区系成分热带性质较强,热带性的科有78科,占总科数的69.64%,其中泛热带分布科有47科,占41.96%,是最大的类型.泛热带和热带亚洲成分的属占优势,各占非世界属总数的33.47%和19.62%;中国特有属有3属,分别为驼峰藤属(Merrillanthus)、海南椴属(Hainsnia)和乐东藤属(Chunechites),其分布中心为海南岛.热带成分的种占非世界种数的74.94%,明显处于优势地位;中国特有种有204种,占总种数的23.13%,其中海南特有种有78种.与琼北地区种子植物区系比较,两地种子植物区系在物种组成上有明显差异,主要是由于两地不同的气候和地质等自然地理环境因素的区域分异引起的.  相似文献   

8.
海南热带雨林国家公园拥有我国最具代表性、连片面积最大的热带雨林,生态产品丰富,在开展国家公园生态产品价值实现机制探索上具有得天独厚的优势。本研究基于《陆地生态系统生产总值(GEP)核算技术指南》框架,构建符合热带雨林国家公园特色的GEP核算体系,对2019年海南热带雨林国家公园GEP进行核算。结果表明: 2019年,海南热带雨林国家公园GEP为2045.13亿元,单位面积GEP为0.46亿元·km-2。其中,物质产品价值为48.50亿元,占国家公园GEP总量的2.4%;生态系统调节服务价值为1688.91亿元,占82.6%;文化服务价值为307.72亿元,占15.0%。从不同生态系统类型来看,以山地雨林、低地雨林、落叶季雨林、热带云雾林等为代表的热带雨林生态系统的单位面积价值量远高于人工林及其他生态系统,表明热带雨林生态系统在提供生态系统服务功能方面具有显著作用。此外,本研究还基于国家公园GEP核算结果,提出进一步探索生态产品价值实现路径和实现机制的相关建议。  相似文献   

9.
云南樟科植物区系地理   总被引:5,自引:2,他引:3  
李捷 《云南植物研究》1992,14(4):353-361
  相似文献   

10.
首次报道了豆科(Fabaceae)山扁豆属四叶山扁豆[Chamaecrista absus(L.)H.S.IrwinBarneby]在中国的新分布,并提供该种的特征描述。  相似文献   

11.
陈圣天  付晖  杜彦君  付广  陈杰 《广西植物》2023,43(9):1688-1699
海南热带雨林国家公园森林资源富集,探究该地区景观格局时空演变特征,对维护海南岛生态安全屏障具有重要意义。该研究依托2015年和2020年海南热带雨林国家公园地表覆盖数据,建立景观分布格局体系,采用景观格局指数、单一景观动态度和景观转移矩阵的方法,分析海南热带雨林国家公园10类土地覆盖类型的景观格局变化特征,探究其变化的影响因素。结果表明:(1)2015—2020年,海南热带雨林国家公园整体景观破碎度呈现降低趋势,空间集聚性增加,综合动态度较小,景观类型整体较稳定。(2)雨林优势种常绿阔叶林面积不断增加,破碎度减小,呈正向增长态势;针叶林与灌木林面积减少;部分水体转化为湿地等,面积减小;其余景观类型面积占比较小,按自然演替方向发展变化。(3)景观格局演变主要以雨林自然演替为主,其次受政策、气候等因素综合影响。综上所述,自开展海南热带雨林国家公园体制试点以来,其景观格局趋于稳定。政策引导发挥着重要的正向作用,有针对性地开展热带雨林景观保护及修复工作,有助于海南热带雨林国家公园可持续发展。  相似文献   

12.
Lymphatic filariasis is endemic in India. Out of 128 million infected individuals worldwide, India accounts for 48 million cases [Manson's Tropical Diseases, 21st Ed. p 1488]. Filariasis can have protean manifestations, but Tropical pulmonary eosinophilia and chyluria are unusual manifestations reported mainly from South Asian countries [Manson's Tropical Diseases, 21st Ed. p 1494]. Chyluria occurs only in 2% of filarial afflicted patients in the filarial belt [Diamond E, Schapira HE. Chyluria--a review of literature. Urology 1985;26(5): 427-31]. Lymphatic filariasis presenting as chyluria may be equally rare. Predominant chyluria with no overt lymphatic filariasis remains an enigma.  相似文献   

13.
An Introduction to Tropical Rain Forests (2nd edn) by T.C. Whitmore Oxford Science Publications, 1998. £45 hbk, £19.50 pbk (224 pages) ISBN 0 19 850148 X/0 19 850147 1 Tropical Rain Forest: A Wider Perspective edited by F.B. Goldsmith Chapman and Hall (Conservation Biology Series) 1998. £69.00 hbk (xix+416 pages) ISBN 0 412 81510 9 Vanishing Treasures of the Philippine Rain Forest by L.R. Heaney and J.C. Rigalado Jr University of Chicago Press, 1998. £19.25/$24.00 pbk (96 pages) ISBN 0 91486819 5.  相似文献   

14.
Several ecological and evolutionary processes can drive changes in diversity at different spatial scales. To determine the scale at which these processes are most influential, we hypothesized that (i) broad‐scale differences between ecoregions had greater influence on ant species richness and species turnover than local differences among fragments within ecoregions; and (ii) the degree of dissimilarity in ant species composition is larger between Tropical Dry Forest fragments and the surrounding vegetations than among Tropical Dry Forests located in different ecoregions, indicating that extant Tropical Dry Forests are relicts of a broader distribution of this vegetation. To examine ant diversity patterns, we built a nested hierarchical design on three spatial scales, ranging from fragments (local scale), Tropical Dry Forest + surroundings vegetation (landscape scale) and Brazilian ecoregions (regional scale). We used 450 sampling units (45 sampling units × two fragments × five ecoregions = 450). A null model based on the sample was used to identify variations in the random distribution across spatial scales. Spatial partitioning of ant diversity showed that observed β1 diversity (between fragments) and β2 diversity (among ecoregions) were higher than expected by chance. When the partitioning was analysed separately for each region, the observed β1 diversity (Tropical Dry Forest and surrounding vegetation) was higher than expected by the null hypothesis in all ecoregions of Brazil. Based on species composition and diversity patterns, we stress the importance of creating more protected areas throughout the coverage area of Tropical Dry Forests, favouring a more efficient conservation process.  相似文献   

15.
报道了中国锦葵科(Malvaceae)一新记录属——沙稔属(Sidastrum Baker f.),小花沙稔[Sidastrum micranthum (A. St.-Hil.)Fryxell]首次在广东发现。  相似文献   

16.
中国海南岛灵芝资源及其分布特征*   总被引:1,自引:0,他引:1  
本文报道了海南岛的灵芝科真菌78种,分属于4个属,3个亚属,2个组。分析了灵芝在不同的热带植被类型中,其种类的组成不同。种类多样性变化呈:常绿季雨林>热带雨林>低山雨林>中山雨林>热带半落叶季雨林>人工林>河谷雨林>稀树草原>山顶矮林>红树林的趋势  相似文献   

17.
Global seagrass distribution and diversity: A bioregional model   总被引:5,自引:0,他引:5  
Seagrasses, marine flowering plants, are widely distributed along temperate and tropical coastlines of the world. Seagrasses have key ecological roles in coastal ecosystems and can form extensive meadows supporting high biodiversity. The global species diversity of seagrasses is low (< 60 species), but species can have ranges that extend for thousands of kilometers of coastline. Seagrass bioregions are defined here, based on species assemblages, species distributional ranges, and tropical and temperate influences. Six global bioregions are presented: four temperate and two tropical. The temperate bioregions include the Temperate North Atlantic, the Temperate North Pacific, the Mediterranean, and the Temperate Southern Oceans. The Temperate North Atlantic has low seagrass diversity, the major species being Zostera marina, typically occurring in estuaries and lagoons. The Temperate North Pacific has high seagrass diversity with Zostera spp. in estuaries and lagoons as well as Phyllospadix spp. in the surf zone. The Mediterranean region has clear water with vast meadows of moderate diversity of both temperate and tropical seagrasses, dominated by deep-growing Posidonia oceanica. The Temperate Southern Oceans bioregion includes the temperate southern coastlines of Australia, Africa and South America. Extensive meadows of low-to-high diversity temperate seagrasses are found in this bioregion, dominated by various species of Posidonia and Zostera. The tropical bioregions are the Tropical Atlantic and the Tropical Indo-Pacific, both supporting mega-herbivore grazers, including sea turtles and sirenia. The Tropical Atlantic bioregion has clear water with a high diversity of seagrasses on reefs and shallow banks, dominated by Thalassia testudinum. The vast Tropical Indo-Pacific has the highest seagrass diversity in the world, with as many as 14 species growing together on reef flats although seagrasses also occur in very deep waters. The global distribution of seagrass genera is remarkably consistent north and south of the equator; the northern and southern hemispheres share ten seagrass genera and only have one unique genus each. Some genera are much more speciose than others, with the genus Halophila having the most seagrass species. There are roughly the same number of temperate and tropical seagrass genera as well as species. The most widely distributed seagrass is Ruppia maritima, which occurs in tropical and temperate zones in a wide variety of habitats. Seagrass bioregions at the scale of ocean basins are identified based on species distributions which are supported by genetic patterns of diversity. Seagrass bioregions provide a useful framework for interpreting ecological, physiological and genetic results collected in specific locations or from particular species.  相似文献   

18.
Extant variants of henequen (Agave fourcroydes Lem.) and wild populations of its putative ancestor A. angustifolia Haw. were grown in the Mexican state of Yucatan for 10 yr under homogeneous conditions. A statistical and numerical analysis of their patterns of morphological variation was performed as part of broader research to provide evidence of its genetic diversity, evolutionary relationships and changes under human selection. A comparison with results of a similar analysis under natural growing conditions was also made. The study indicated the following. (1) Under natural growth conditions, the three putative wild ecotypes are morphologically distinct, but under uniform conditions only populations growing in Tropical subdeciduous forest may be distinguished from the other two, thus indicating the probable existence of only two ecotypes: one growing in Coastal dunes and Tropical subdeciduous forest, and the other growing in Tropical deciduous forest. (2) This last ecotype is the most similar to cultivated variants. Within its populations, the most similar to the cultivated is that known as Chelem White, gathered by artisans for its textile use. (3) The cordage-cultivated Sac Ki and Yaax Ki differ from wild populations in four syndromes of domestication: gigantism, greater fibrosity, less thorniness, and less reproductive capacity. The lower cv of their characteristics compared with those of wild populations suggest less genetic diversity. (4) Kitam Ki is probably a textile-cultivated variant of recent introduction and/or a variant in which the artificial selection process has had different direction and intensity. (5) Improved growth conditions in the botanic garden resulted in a decreased cv, an increase in size and fiber content, and a reduction of thorniness for both wild and cultivated variants. Given that wild populations with desirable characteristics exist and that these characteristics are highly plastic and respond positively to cultivation, then selection and cultivation of populations such as those from Tropical deciduous forest may well have been the path taken by the ancient Maya during henequen domestication.  相似文献   

19.
Review of the traditional separation of global Ordovician conodont distribution into the North American Midcontinent Province (NAMP) and North Atlantic Province (NAP) reveals a confusing variety of concepts and definitions that hinder biogeographic analysis. Use of this twofold scheme and its subsequent variants should be­discontinued in favour of the more detailed divisions proposed here. Major biogeographical entities of the Shallow-Sea and Open-Sea Realms, separated by the shelf-slope break, are both further subdivisible into Tropical, Temperate and Cold Domains. In the Cold domains, faunal differences between the two Realms and their subdivisions are not easily discernible, since biofacies zones and different habitats were highly condensed. Faunal differences are amplified in the tropical regions, where the North American Midcontinent Province and North Atlantic Province were originally defined. Recognition of endemic taxa is essential for finer classification within domains of the Shallow-Sea Realm (SSR). Our preliminary analysis of Early Ordovician conodont distribution identifies the Laurentian Province (in the Tropical Domain), Australian­(Tropical Domain), North China (Tropical Domain), South China (Temperate Domain), Argentine Precordillera (Temperate Domain) and Balto-Scandian Province (in the Cold Domain). The Open-Sea Realm (OSR) is dominated by cosmopolitan and widespread taxa, and formal subdivision at provincial level is yet to be achieved. The North Atlantic Province encompasses both the Open-Sea Realm and the Temperate and Cold Domains of the Shallow-Sea Realm. The North American Midcontinent Province sensu stricto is more or less equivalent to the Laurentian Province, representing shallow-water regions fringing Laurentia; in a broader sense the North American Midcontinent Province includes all provinces of the Tropical Domain within the Shallow-Sea Realm.  相似文献   

20.
Timber Production and Biodiversity Conservation in Tropical Rain Forests by A.G. Johns Cambridge University Press, 1997. £40.00/$69.95 hbk (xvii+225 pages) ISBN 0 521 57282 7.  相似文献   

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