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1.
气候制约着植被的地理分布,植被是区域气候特征的反映和指示,两者之间存在密不可分的联系.揭示植被与气候之间的关系是正确认识植被分布的前提,是进行植被区划的理论基础.植被区划是植被研究的归纳和总结,是其他自然地理区划和农林业区划的基础.本文在简要回顾中国植被气候关系及植被分区的研究历史的基础上,对我国以往的主要植被分区原则、依据和方案进行了评述,对有争议的主要植被界线进行了讨论.我们认为,在当今我国大部分地区的原生植被已遭到破坏的现实情况下,根据原生植被及其衍生植被类型的分布,确定其分布与限制性气候因子的关系,以此来进行植被带(区)的划分,不仅反映植被气候间密不可分的关系,在实践上也便于操作.尽管在一些植被带的命名、具体界线的划定上有分歧,但最近的中国植被分区方案大都认为我国基本的植被区有8至9个,即针叶林、针阔叶混交林、落叶阔叶林、常绿落叶阔叶混交林、常绿阔叶林以及雨林季雨林、草原、荒漠以及高寒植被.通过分析主要植被带附近的植被、气候等特征,本文认为,1)秦岭淮河线是一条重要的水分气候带,而不是温度带,不是亚热带植被的北界;2)我国亚热带植被的北界基本上沿长江北岸,从杭州湾经太湖、安徽宣城、铜陵经大别山南坡到武汉往西,与WI值130-140 ℃·月一致;3)我国热带区域的面积极小,仅分布在海南岛的东南部和台湾南端及其以南地区; 4) 我国东部地区暖温带的水热条件南北差异甚大,建议以秦岭淮河为界,将暖温带划分为两个植被带,即落叶阔叶疏林带和落叶常绿阔叶混交林带;华北地区的地带性植被为落叶阔叶疏林.最后,本文还强调了对应于气候变化进行动态植被分区的重要性.  相似文献   

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一.引言长期以来,人们都认为秦岭、淮河一线是我国自然地理的南北分界线。在植物分布上常有“杉木不过淮水”、“橘子过淮便成枳”等的记载,都说明淮河南北的植物分布和生长上的差异。但是淮河自安徽流入江苏洪泽湖以后,河湖合而为一,在苏北不再有淮河的主流,因此在这一地区缺乏明显的界线标志,从而对于植物南北分界的具体位置就出现了不同的意见。在苏北地区,许多植物学家都以北纬33—34°之间作为植物的南北分界綫,此线以北属于华北落叶阔叶林区,以南为华中常绿阔叶-落叶阔叶混交林区。在过去的植被区划中,都认为常绿阔叶林的北界不超过北纬34°。  相似文献   

3.
气候制约着植被的地理分布,植被是区域气候特征的反映和指示,两之间存在密不可分的联系。揭示植被与气候之间的关系是正确认识植被分布的前提,是进行植被区划的理论基础,植被区划是植被研究的归纳和总结,是其他自然地理区划和农林业区划的基础,本在简要回顾中国植被气候关系及植被分区的研究历史的基础上,对我国以往的主要植被分区原则,依据和方案进行了评述,对有争议的主要植被界线进行了讨论,我们认为,在当今我国大部分地区的原生植被已遭到破坏的现实情况下,根据原生植被及其衍生植被类型的分布,确定其分布与限制性气候因子的关系,以此来进行植被带(区)的划分,不仅反映植被气候间密不可分的关系,在实践上也便于操作,尽管在一些植被带的命名,具体界线的划定上有分歧,但最近的中国植被分区方案大都认为我国基本的植被区有8至9个,即针叶林、针阔叶混交林、落叶阔叶林、常绿落叶阔叶混交林,常绿阔叶林以及雨林季雨林,草朱、荒漠以及高寒植被,通过分析主要植被带附近的植被,气候等特征,本认为,1)秦岭淮河线是一条重要的水分气候带,而不是温度带,不是亚热带植被的北界;2)我国亚热带植被的北界基本上沿长江北岸,从杭州湾经太湖、安徽宣城、铜陵经大别山南坡到武汉往西,与WI值130-140℃,月一致;3)我国热带区域的面积极小,仅分布在海南岛的东南部和台湾南端及其以南地区;4)我国东部地区暖温带的水热条件南北差异甚大,建议以秦岭淮河为界,将暖温带划分为两个植被带,即落叶阔叶林疏林带和落叶常绿阔叶混交林带,华北地区的地带性植被为落叶阔叶疏林,最后,本还强调了对应于气候变化进行动态植被分区的重要性。  相似文献   

4.
植被气候关系与我国的植被分区(英文)   总被引:17,自引:0,他引:17  
气候制约着植被的地理分布 ,植被是区域气候特征的反映和指示 ,两者之间存在密不可分的联系。揭示植被与气候之间的关系是正确认识植被分布的前提 ,是进行植被区划的理论基础。植被区划是植被研究的归纳和总结 ,是其他自然地理区划和农林业区划的基础。本文在简要回顾中国植被气候关系及植被分区的研究历史的基础上 ,对我国以往的主要植被分区原则、依据和方案进行了评述 ,对有争议的主要植被界线进行了讨论。我们认为 ,在当今我国大部分地区的原生植被已遭到破坏的现实情况下 ,根据原生植被及其衍生植被类型的分布 ,确定其分布与限制性气候因子的关系 ,以此来进行植被带 (区 )的划分 ,不仅反映植被气候间密不可分的关系 ,在实践上也便于操作。尽管在一些植被带的命名、具体界线的划定上有分歧 ,但最近的中国植被分区方案大都认为我国基本的植被区有 8至 9个 ,即针叶林、针阔叶混交林、落叶阔叶林、常绿落叶阔叶混交林、常绿阔叶林以及雨林季雨林、草原、荒漠以及高寒植被。通过分析主要植被带附近的植被、气候等特征 ,本文认为 ,1)秦岭淮河线是一条重要的水分气候带 ,而不是温度带 ,不是亚热带植被的北界 ;2 )我国亚热带植被的北界基本上沿长江北岸 ,从杭州湾经太湖、安徽宣城、铜陵经大别山南坡到武汉  相似文献   

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简要回顾了中国东部森林植被带划分研究的历史及当前存在的争论。提出了中国东部植被带划分应以植被本身的特征,特别是地带性的生物群落集为主要依据,同时参照它们的区系组成和气候指标。根据上述原则将中国东部划分为6个植被带∶北方针叶林带、凉温带针阔混交林带、温带落叶阔叶林带、暖温带常绿落叶阔叶混交林带、亚热带常绿阔叶林带和热带雨林、季雨林带,并对各植被带的特征作了简要的描述。阐述了对一些植被带名称、界线改动的原因,特别讨论了我国常绿落叶阔叶混交林以及常绿阔叶林生物气候带的归属问题,认为前者归属于暖温带植被,后者归属于亚热带植被为宜。  相似文献   

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中国东部森林植被带划分之我见   总被引:27,自引:0,他引:27  
简要回顾了中国东部森林植被带划分研究的历史及当前存在的争论。提出了中国东部植被带划分应以植被本身的特征,特别是地带性的生物群落集为主要依据,同时参照它们的区系组成和气候指标。根据上述原则将中国东部划分为6个植被带∶北方针叶林带、凉温带针阔混交林带、温带落叶阔叶林带、暖温带常绿落叶阔叶混交林带、亚热带常绿阔叶林带和热带雨林、季雨林带,并对各植被带的特征作了简要的描述。阐述了对一些植被带名称、界线改动的原因,特别讨论了我国常绿落叶阔叶混交林以及常绿阔叶林生物气候带的归属问题,认为前者归属于暖温带植被,后者归属于亚热带植被为宜。  相似文献   

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价值和利用     
猫儿山具有较大面积的东亚湿润亚热带特有植被类型。保护区范围从海拔300米一直到最高峰,植被垂直分带明显,从常绿阔叶林带,到山地常绿、落叶阔叶混交林带,再到常绿、落叶阔叶混交矮林和灌丛带,依次出现,各个植被带都有面积大小不等的一些演替类型出现,生物多样性丰富多彩。猫儿山同时也是漓江,资江和浔江三大水系的主要发源地。特别是漓江的水量和水质与猫儿山地区森  相似文献   

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正安徽大别山区位于皖中西部,面积8 200 km2,为山地丘陵区,植被区划较为复杂,北部为北亚热带落叶与常绿阔叶混交林带,南部为中亚热带常绿阔叶林带[1-3]。该区域的植物区系属于中国-日本森林植物区系的华东区系,物种丰富,其中,蕨类植物142种(含种下分类单位),鳞毛蕨科(Dryopteridaceae)、水龙骨科(Polypodiaceae)和蹄盖蕨科(Athyriaceae)的种类较多,占据优势[4]。从2015年6月起,作者对皖西大别山进行了野外调查,  相似文献   

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神农架自然遗产地植被垂直带谱的特点和代表性   总被引:1,自引:0,他引:1       下载免费PDF全文
充分认识并掌握我国自然遗产地山地植被垂直带谱代表性,对正确评估自然遗产地的价值进而制定相关保护管理政策具有重要的科学意义和现实意义。该研究基于群落调查数据、全球1 km~2土地利用数据,通过对比分析、空间分析等方法,从植被垂直带谱的地带性、完整性及不同垂直带群落物种更替等角度,分析论证了神农架自然遗产地植被垂直带谱的代表性。结果显示:神农架自然遗产地从低海拔到高海拔依次发育有常绿阔叶林带(遗产地南坡)、常绿落叶阔叶混交林带、落叶阔叶林带、针阔混交林带、针叶林带及亚高山灌丛和草甸带,其北坡保存的地带性常绿落叶阔叶混交林是北半球常绿落叶阔叶混交林生态系统的最典型代表。神农架自然遗产地拥有的植被垂直带谱是"全球生物地理区划"中东方落叶林生物地理省最完整的植被垂直带谱,在东方落叶林生物地理省具有唯一性和代表性,在较小的水平距离范围内浓缩了中亚热带、北亚热带、暖温带、温带和寒温带等生态系统特征,成为研究全球气候变化下山地生态系统垂直分异规律及其生态学过程的杰出范例,具有突出的世界自然遗产价值。  相似文献   

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 本文对陕西省化龙山植被的垂直分布特点进行了初步研究。文中采用了数量分类结合对群落生态特点及区系组成的分析,划分出森林植被垂直带如下:常绿、落叶阔叶混交林带,海拔1600m以下;落叶阔叶林带,海拔1600—2200m;亚高山针叶林带,海拔2200—2917m。  相似文献   

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On the origin of the Hirudinea and the demise of the Oligochaeta   总被引:10,自引:0,他引:10  
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.  相似文献   

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Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor  相似文献   

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