【作者】 岳秀贤；

【导师】 刘果厚；

【作者基本信息】 内蒙古农业大学 ， 野生动植物保护与利用， 2011， 博士

【摘要】 蒙古高原位于亚洲腹地干旱、半干旱地区,植物区系在世界区系中具有一定的代表性。本研究运用植物区系地理学基本原理,结合实地植被调查以及大量文献资料查阅,对蒙古高原植物区系组成、地理成分、生活型、水分生态型、起源与演化、区系分区及珍稀濒危植物进行了分析研究,结论如下:1、植物种类较贫乏。蒙古高原共有种子植物115科、761属、4280种(含种下分类单位)。其中,裸子植物3科、8属、32种;被子植物112科、753属、4248种。2、区系组成复杂多样。区系组成虽以单种科、寡种科、单种属和寡种属为主,但植物种类大多数集中于大型科、大型属、中等属和寡种属,它们均是植物区系复杂性及物种多样性的主要来源;中型科和较大科、属虽在数量上不占主体,但却对区域植物的构成及植被的分布格局具有很大的影响。3、区系成分复杂,联系广泛。各种区系成分在蒙古高原地区的相互渗透,相互联系,使得蒙古高原植物区系变得复杂多样,而且在一定程度上具有过渡性质。区系中温带成分占绝对优势,为典型的北温带性质。4、本区属于泛北极植物区系的一部分。根据植物地理学的区划原则和蒙古高原的地貌特征、植物区系分布的基本特征,可将蒙古高原植物区系划分成4个亚区、5个地区、9个省、30个县。5、根据R/T值(热带性质属与温带性质属的比例)的大小排列,对蒙古高原9个植物省的植物区系进行比较。结果显示:随纬度的升高,R/T值呈下降趋势,即温带性质加强;运用SAS软件中的聚类分析方法,对各植物省的区系组成相似性进行定量分析,结果表明:外贝加尔植物省和杭爱山地森林草原省的相似性最高,阿尔泰山地草原省和北戈壁荒漠草原省次之。6、特有程度低。蒙古高原种子植物761属中有10个为蒙古高原特有,占总属数的1.46%(不含世界分布属),特有种255个,占总种数的5.96%。7、蒙古高原种子植物区系以草本植物占优势,其中,含草本的科、属、种数分别占总科、属、种的80.9%、85.4%和85.1%。8、水分生态型以中生植物为主,占总种数的64.6%,旱生植物次之,占26.8%。9、珍稀濒危植物较多。结合蒙古高原种子植物的地理分布、种群数量及生态环境等实际情况,采取定量和定性相结合的原则,将蒙古高原珍稀濒危植物的濒危等级划分为:濒危、渐危和稀有3个等级;保护级别划分为一级、二级、三级3个保护级别。本区有一级保护植物4种,二级保护植物33种,三级保护植物68种。10、本区植被以亚洲中部草原和荒漠植物为主要组成部分。蒙古高原是欧亚大陆地带性植被尤其是草原植被分布的主要区域,该区系也是世界植物区系的重要组成部分。11、植物区系在起源上新老并存,以新生进化成分为主。蒙古高原植物区系主要是在古地中海沿岸或遗迹上发生,并有部分是从本地的荒漠环境中发展起来的;还有由其他植物区系(东亚成分、温带成分)迁移而来,并在此独特环境中蜕变的结果。更多还原

【Abstract】 Mongolian plateau located in the Arid and Semi-arid Areas in Asia hinterland, and the flora in this region was a representative in the world flora. The floristic composition, geographical elements, life form, water ecotype, origin and evolution, floristic regionalization and rare and endangered plants of seed plants in Mongolian plateau, based on vegetation investigation and document data,were studied according to applying some botany and geobotany principle disciplines. The results as follows:(1) The seed plants were relatively indigent. 4280 species plants (ingcluding the subspecies, varieties and forms), belonging to 761 genus and 115 families, distributed in Mongolian plateau regions naturally. Among them, there were 32 gymnosperm species and 4248 angiosperm specie s, belonging to 8 genus and 3 families, 753 genus and 112 families separately.(2) The geographical components of the flora were diverse. The mono-specific family, oligo-specific family, mono-specific genera and oligo-specific genera were the main source of flora complexity and species diversity, which distributed widely in Mongolian plateau. The dominance of the multi-specific family, multi-specific genus, mid-specific genera and oligo-specific genera were evident in the number of species. In many cases, mid-specific family, plum-specific family and plum-specific genera have significant influence to the structure of flora and vegetable composition, though they are not dominant species of local plant community and the representative components.(3) The flora in this region, which consisted of complicated geographic element, interconnected and interpenetrated with other flora broadly. The transition of the flora was obvious to a certain extent. Temperate element took the predominated position and owned the typically North Temperate character.(4) This flora was a part of the Holarctic region. According to the geobotanical principle and the basic characteristics of physiognomy flora of Mongolian plateau region, it could be divided into four sub-kingdoms, five regions, nine provinces and thirty districts.(5) According to the ordination of R/T (tropic genera/ temperate generra) of nine provinces, we found the ratio of R/T descended with increasing of latitude and an apparent rule on latitude zonation of floristic variation was expressed. The similar result was obtained through the calculations of shared genera and generic similarity index between nine floras. The results, from cluster analysis on the floristic spectrum, indecated that the closest similarity occurred between External Baikal province and Khangai Mountain forest grassland province. The similarity between Altai Mountain grassland province and North Gobi desert grassland province took the second place.(6) In 761 seed plants genera of Mongolian plateau, 10 endemic genera and 255 special species were included, which was 1.46% of the total genera (not include world distribution) and 5.95% of the total number of species, respectively.(7) Herbage was dominant in life styles in Mongolian plateau. Families, genera and specie, which include herbaceous plants, account for 80.9% of the seed plants families, 85.4% of genera and 85.1% of species in this region resperctively.(8) In water ecotypes, the mesophytes and the xerophils were primary, accounting for 64.6% and 26.8% resperctively.(9) More rare and endangered plants distributed on the Mongolian plateau. The qualitative and quantitative principles were adopted to determine the threatened status of the rare and endangered plants in Mongolian plateau according to the study on the plants geographic distribution, population and ecological environment. Three categories were determined, namely Endangered, Vulnerable and Rare plant. The protected priority was divided into three classes, and the number of the protected plants in first class was 4, the second class was 33 and the third class was 68 in Mongolian plateau regions.(10) Mongolian plateau was not only the main distribution area for zonal vegetation of the Eurasian continent, especially for grassland vegetation, but also one of important parts in the world flora.(11) Both palaeo-elements and neo-elements can co-exist in this region, but the neo-elements were dominant. Most of the elements of this flora oringined from coastwise and traces of Tethys, but some of them formed in the desert environment, some of them, such as East-Asia and Temperate elements, others elected and differentiated in idiographic environment, transferred from other floras.更多还原