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1.
青海省大柴旦盆地植被   总被引:4,自引:0,他引:4  
大柴旦盆地属于茺漠植被区域。在盆地中,从洪积平原到湖积平原依次发育着矮半灌木、灌木砾漠,矮半灌木沙漠,禾草、杂类草盐生草甸,芦苇(Phragmites communis)盐沼泽。周围山地自低而高依次发育着矮半灌木,灌木低山石漠,小叶金露梅(Dasiphora parvifolia)亚高山灌丛,紫花针茅(Stipa purpurea)高寒草原和矮嵩草(Kobresia humilis)高寒草甸,高山稀疏植被。由于地形封闭,这里残存了在柴达木盆地其它地区已消失的一些植被类型,有些植物种远离其主分布区达500km以上。盆地海拔基准高达海拔3500m,加上山地的屏蔽作用向上逐渐减弱,致使气温的垂直递减率较大,在垂直带谱中缺失山地草原和针叶林等中山带植被。此外,盆地中湖积平原富积硼酸盐,使盐生草甸中的优势种之一盐角草(Salicornia herbacea)发生变态,这是本区植被中出现的一个有重要科学意义的指示植物现象。  相似文献   

2.
中昆仑山北坡及内部山原的植被类型   总被引:3,自引:0,他引:3       下载免费PDF全文
 中昆仑山西始乌鲁乌斯河,东迄安迪河,东西迤逦600余公里,平均海拔高度6000m。该区有野生种子植物52科,211属,398种。植物区系以种类成份单纯、地理成份复杂为特征。北坡中山带和高山带下部年降水量300—500mm,草原带发育完整,尤以中段的策勒山地草原发育最好。草原带以上高寒荒漠不存在,高寒草甸则有一定发育。中昆仑山北坡植被类型的垂直带谱是:1)山地荒漠,自山麓线多在2200—2500m,个别在3000m;2)山地荒漠草原在3000—3200m;3)山地真草原在3200—3600m;4)高寒草原在3600—3800m(阳坡上升到4200m以上);5)高寒草甸在3800—4200m;6)高山垫状植被仅见于东段山地和高寒草甸复合分布;7)高山流石坡稀疏植被在4200—5000m。中昆仑山内部山原极端寒冷干旱,多为砾漠所占据,高寒荒漠和高寒荒漠草原呈片状星散分布。  相似文献   

3.
二、荒漠、裸露荒漠带本带是我国极端干旱地区,年降水量一般低于50—100毫米,包括塔里木盆地、东疆和柴达木盆地。塔里木盆地和东疆海拔1000—1500米,属暖温带气候。≥10℃年积温为3800—4700℃,年均温约为10—20℃;一月均温为-6到-10℃,绝对最低为-16.9℃;7月均温为25—26℃,绝对最高为43.6℃;无霜期186—230天。全境有不少面积为无植被的流动沙丘和裸露砾漠。在塔里木盆地超旱生的灌木荒漠最为突出,在山前洪积扇上有极稀疏的膜果麻黄、木坝王、泡泡刺、沙拐枣砾漠,盆地中间有极稀疏的柽柳沙漠。低  相似文献   

4.
调查和分析甘肃省祁连山西段及酒泉盆地草地和植被资源及其分布规律,发现该区草地类型主要为沼泽草地、低湿地草甸草地、荒漠草地、山地荒漠草地、荒漠化草原、山地草原、高寒草原、山地草甸、高寒草甸以及高寒荒漠。分析了草地资源现状和合理利用问题,并提出了可持续利用该区草地资源的对策。  相似文献   

5.
青藏高原高山植被的初步研究   总被引:6,自引:0,他引:6       下载免费PDF全文
青藏高原是我国高山植被类型最丰富、独特和分布最广泛的区域,发育有大面积的高山灌丛、高寒草甸、高寒草原,高寒荒漠、高山流石坡稀疏植被及零散分布的高山垫状植被。它们占据着森林上线至永久雪线之间的高山带和广阔的高原面,从高原东南部至西北部有水平方向的地域分异。联系高山带以下各垂直带的植被特征及各地的气候条件分析,初步认为高原东南部的山地植被垂直带谱属于湿润型山地垂直带结构类型,高原腹地及西北部的山地植被垂直带谱属于干旱型山地垂直带结构类型。此外,还对青藏高原高山植被类型的丰富性及高山垫状植被的生态地理分布特点进行了初步探讨。  相似文献   

6.
西藏植被的高原地带性   总被引:15,自引:0,他引:15  
1.西藏高原的植被不同于一般的“水平地带”植被,也不同于山地的“垂直带”植被。它是属于“准平原式”的垂直带植被,可称之为“高原地带”植被。2.西藏植被的成带现象自东南向西北变化如下:森林—草甸—草原—荒漠。这些高原地带性的形成主要取决于高原巨大幅度的隆升及其所引起的特殊的大气环流状况。潮湿的西南季风乃是西藏东南部热带和亚热带山地森林发育的基本因素。高原面处在西风环流和“青藏高压”控制下,在这种大陆性高原的气候条件下,形成了高寒草甸、草原和荒漠植被。  相似文献   

7.
新疆阿勒泰地区草地类型及植物多样性的研究   总被引:15,自引:0,他引:15  
基于33个样地、99个样方的野外调查资料,分析了新疆阿勒泰地区草地群落的植物物种多样性特征。结果表明:草地群落间的植物物种丰富度指数、均匀度指数和多样性指数差异显著,丰富度由山地草原、经山地草甸、荒漠草原、草甸化草原、平原荒漠、高寒草甸到山地荒漠依次下降,均匀度指数由山地草原,经草甸化草原、荒漠草原、平原荒漠、山地草甸、高寒草甸,到山地荒漠依次下降,多样性指数从山地草原,经草甸化草原、荒漠草原、山地草甸、平原荒漠、高寒草甸,到山地荒漠呈下降趋势。在群落多样性梯度上,物种丰富度对多样性的贡献率要比均匀度的贡献率小。草地群落的物种丰富度、均匀度和多样性指数随海拔升高均表现为先上升,后下降,峰值出现在1800~2000m的山地草原,且变化趋势一致。  相似文献   

8.
 在青藏高原的西北部,喜马拉雅山、喀喇昆仑山和昆仑山汇聚成一个高大山系组。中国-巴基斯坦公路横跨这个山系组,沿线植被的组成及分布显示出极其明显的地域分异:西昆仑山和喀喇昆仑山以荒漠为主,西北喜马拉雅山以山地森林为主;西昆仑山前平原上是暖温带灌木、半灌木荒漠,西北喜马拉雅山前印度河平原上是亚热带稀树草原;山系组腹地谷坡明显较外部山坡干燥,西昆仑山东北坡有完整的山地草原和高山草甸带,以及断续的山地云杉(Picea)和刺柏(Juniperus)疏林灌丛,而西南坡山地荒漠海拔高达3600~4000 m,草原和草甸带  相似文献   

9.
青海可可西里地区的植被   总被引:4,自引:0,他引:4       下载免费PDF全文
郭柯 《植物生态学报》1993,17(2):120-132
青海可可西里地区位于青藏高原腹地,总面积8万多平方公里,平均海拔高度4600—5000m,是青藏高原,也是我国植被科学研究最大的空白地区。 根据1990年夏为期3个月的实地考察,发现本区由东南到西北主要分布着高寒草甸,高寒草原和高山冰缘植被。垫状植被、高寒荒漠和高山河谷灌丛等也有分布。植物区系组成以青藏高原成分为主,其次为中亚高山分布的种。各种植被类型的分布往往与地形部位和基质状况存在着密切的联系。  相似文献   

10.
以西藏高原高寒草原生态系统的4个自然地带(高山草原、高山灌丛草甸、山地半荒漠与荒漠以及山地灌丛草原)的19个草地型植被为研究对象,采用野外调查与室内分析相结合的方法,对高寒草原生态系统植被C/N值的分布特征及其影响因素进行了研究。结果表明:西藏高原高寒草原植被C/N值总体上呈现出东西部低而中间高的态势以及斑块状交错分布的格局。不同自然地带间和不同草地型间植被地上部分和根系的C/N值有明显差异,且地上部分的C/N值均大于根系。19个草地型植被地上部分的平均C/N值为34.17,变异系数为35.87%;根系的平均C/N值为29.58,变异系数为40.02%。4个自然地带植被地上部分的平均C/N值为31.98,变异系数为13.82%;根系的平均C/N值为31.86,变异系数为16.92%。回归分析结果显示:植被地上部分C/N值与地上部生物量以及土壤全N和全K含量呈显著正相关、与植被高度呈显著负相关;根系C/N值与海拔和20~30em土壤容重呈显著正相关、与年均降水量和年均蒸发量呈显著负相关,这些因子均为影响西藏高原高寒草原植被C/N值的关键环境因子。总体上看,地理因子、气候因子和土壤物理因子对西藏高原高寒草原生态系统植被C/N值的影响不显著,而植被因子和土壤化学因子则对其有显著影响。  相似文献   

11.
青海省芨芨草草原的群落特征及其分布规律   总被引:17,自引:3,他引:14  
芨芨草(Achnatherum splendens)是一种旱生植物,广泛分布于欧亚草原和荒漠地区。它是一种生态可塑性很强的植物,可分布于草原、荒漠草原等植被带内。以其为优势种可以形成盐生草甸、草原、荒漠草原等多种植被类型。青海省共和盆地、青海湖盆地和柴达木盆地东部等地大面积分布有芨芨草群落,并和本区分布的其他草原类型形成基带植被。无论是其生境条件、生物生态学特性、群落的组成及分布规律均具有草原性质,应划归草原植被类型较为合适。  相似文献   

12.
The steppe vegetation of the Xizang (Tibet) Plateau is somewhat similar to the temperate steppe of our country, but it possesses its own characteristics: 1. The elements of the Qinghai-Xizang floral region or plant species taking the Qinghai-Xizang Plateau as their chief distribution center play a dominant part in tile constitution of the steppe communities. In these communities, the plants are usually sparse and dwarf, their growth period is shorter and the biological productivity is lower than the steppe in the temperate zone. They possess synusia consisting of herbaceous plants fit for cold climate, synusia consisting of kobresia and synusia consisting of cushion plants. 2. There are 4 types of steppe vegetation in the Xizang Plateau. And the tussock-grass steppe is the most typical. According to their different ecological characteristics, they may be divided into 3 types. Of these, the most widely distributed type is the cold temperate-weak semiarid steppe. And there are many characteristical steppe communities. 3. Distributionally, the steppe in the Xizang Plateau belongs to a special type of vertical distribution in the subtropical latitude zone, it is different from the gene- rally known montane vertical belt, and possesses a vertical-horizontal distributive nature, i.e. "zonation of plateau". Within the Plateau steppe region, steppe eommunities with different ecological characteristics have clearly marked areal differentiaton, and which has determined the nature of the vertical belts in these areas. According to different basal belts of the vertical belt spectrum, such belts may be divided into 3 types. There are no forests in the montane vertical belt spectra in the Plateau steppe region, and the upper distributional limit of the steppe vegetation reaches an altitude of about 5200 (5400) m., which is the highest distributional limit of steppe on the earth.  相似文献   

13.
贺兰山植物群落类型多样性及其空间分异   总被引:22,自引:1,他引:21       下载免费PDF全文
 贺兰山是一座位于阿拉善高原与银川平原之间的高大山体,是我国西部温带草原与荒漠的分界线和连接青藏高原、蒙古高原及华北植物区系的枢纽。本文就贺兰山植物群落的类型多样性特征及其空间分布规律进行了分析,结果表明:贺兰山植物群落有11个植被型55个群系。垂直分异明显,可划分成山前荒漠与荒漠草原带(海拔1 600 m以下)、山麓与低山草原带(1 600~1 900 m)、中山和亚高山针叶林带(1 900~3 100 m)和高山与亚高山灌丛、草甸带(3 100 m以上)4个植被垂直带。阴阳坡差异很大,在低山带,草原群落多占据阳坡,而阴坡则被中生灌丛所取代;在中山带,阴坡以青海云杉(Picea crassifolia)林为主,阳坡以灰榆(Ulmus glaucescens)、杜松(Juniperus rigida)疏林和其它中生灌丛为主;3 000 m以上阴阳坡分异不明显。东、西坡及南、北、中段植物群落分异也很突出,各自均有一些特殊的群落类型。中段以森林和中生灌丛为主,南段和北段荒漠化程度较高,森林面积很小。北段有四合木(Tetraena mongolica)、沙冬青(Ammopiptanthus mongolicus)、松叶猪毛菜(Salsola laricifolia)等特征群系,南段以贺兰山丁香(Syringa pinnatifolia var. holanshanensis)、斑子麻黄(Ephedra rhytidosperma)等群系最具特色。贺兰山东坡比西坡温暖和干燥,森林面积远小于西坡,并分布一些酸枣(Zizyphus jujuba var. spinosa)、虎榛子(Ostryopsis davidiana)等喜暖中生灌丛。此外,贺兰山还具有贺兰山丁香、斑子麻黄、内蒙薄皮木(Leptodermis ordosica)、贺兰山女蒿(Hippolytia alashanensis)4个特有植物群落。  相似文献   

14.
A study on the vegetation in the east side of Helan Mountain   总被引:7,自引:0,他引:7  
Yuan  Jiang  Muyi  Kang  Shuo  Liu  Lianshu  Tian  Mingde  Lei 《Plant Ecology》2000,149(2):119-130
This paper analyzed the vegetation data obtained from a field survey conducted in the East Side of Helan Mountain, China, to reveal the features of mountainous vegetation growing in a transitional zone between the steppe and desert regions. Detrended correspondence analysis (DCA) was applied to the process of analysis, to clarify the spatial variation of floristic composition of the vegetation in the lower mountain range.The preliminary results obtained from the analysis are: (1) There are 53 vegetation formations existing in the area, following the China's criteria of vegetation classification system. (2) Those vegetation types compose a vertical vegetation spectrum in the East Side of Helan Mountain due to the climatic gradient caused by elevation variation. The spectrum consists of 4 zones. They are, from the foot up to the peak in turn, mountain steppe zone, mountain open forest and steppe zone, mountain coniferous forest zone, and alpine bush and meadow zone. The mountain coniferous forest zone can be further divided into two subzones: Pine forest subzone and Spruce forest subzone. (3) Most of the vegetation types show clear xeromorphic features due to the base zone of the vertical vegetation spectrum lying in the arid region of China. (4) The distribution of vegetation types and flora is sensitive and susceptible to the moisture condition that the vertical vegetation spectrum has quite different expressions between northern and southern exposures. (5) Floristic composition of the vegetation shows a northern temperate feature. The families that are rich in species in the area include Gramineae, Compositae, Leguminosae, Chenopodiaceae, Rosaceae and others, most of which are abundant in herbaceous species. (6) The variation of the ecological conditions from the north to the south also leads to the differentiation of vegetation and its floristic composition in the area. (7) The broad-leaved forest can not form a forest zone in the vertical vegetation spectrum. This may be a special characteristic of the spectrum sitting on a transitional zone between the steppe and desert regions.  相似文献   

15.
Members of the Chenopodiaceae are the most dominant elements in the central Asian desert. The different genera and species within this family are common in desert vegetation types. Should it prove possible to link pollen types in this family to specific desert vegetation, it would be feasible to trace vegetation successions in the geological past. Nevertheless, the morphological similarity of pollen grains in the Chenopodiaceae rarely permits identification at the generic level. Although some pollen classifications of Chenopodiaceae have been proposed, none of them tried to link pollen types to specific desert vegetation types in order to explore their ecological significance. Based on the pollen morphological characters of 13 genera and 24 species within the Chenopodiaceae of eastern central Asia, we provide a new pollen classification of this family with six pollen types and link them to those plant communities dominated by Chenopodiaceae, for example, temperate dwarf semi‐arboreal desert (Haloxylon type), temperate succulent halophytic dwarf semi‐shrubby desert (Suaeda, Kalidium, and Atriplex types), temperate annual graminoid desert (Kalidium type), temperate semi‐shrubby and dwarf semi‐shrubby desert (Kalidium, Iljini, and Haloxylon types), and alpine cushion dwarf semi‐shrubby desert (Krascheninnikovia type). These findings represent a new approach for detecting specific desert vegetation types and deciphering ecosystem evolution in eastern central Asia.  相似文献   

16.
Vegetation of the Nei Monggol (Inner Mongolia) Autonomous Region can be classified into the following four major natural vegetational regions: Eurasia Coniferous Forest Region, East Asia Broad-Leaf Forest Region, Eurasia Steppe Region and Asia-Africa Desert Region. As a result of the differences in the temperature caused by the latitudes and in the precipitation by the southeast monsoon, five zones of vegetation may be distinguished in this region: the bright coniferous forest zone of cold-temperate type, the deciduous broad-leaf forest zone of mid-temperate type, the steppe zone of mid-temperate type, the steppe zone of warm-temperate type and the desert zone of warm- temperate type. Each of them has its own representative of vegetation formation and soil type, with corresponding climatic index. These characteristics have important bearing on the development of agriculture and animal-husbandry in this region. The vegetation of steppe and desert in this region is more arid than the Kazakstan steppe and Middle Asia desert. It is shown by the higher xerophilizaticn of edifieators and the lower productivity of communities. Difference of the characteristics of soil caused by different characteristics of vegetation may also be noticed.  相似文献   

17.
青甘边区黑河流域森林植被带及其昆虫区系的组成   总被引:1,自引:0,他引:1  
黑河发源于青海、甘肃交界的祁连山区,是甘肃河西走廊最大的内陆河水系之一,水源丰富,流量稳定,这不仅取决于祁连山区大气降水和冰川融水,更重要的是与上游森林植被密不可分。但是,由于森林害虫猖獗成灾,严重威胁着这一地域森林的生存。近几年我们在森林昆虫普查的基础上,对黑河流域森林昆虫  相似文献   

18.
小叶、中间和柠条三种锦鸡儿的分布式样及其生态适应   总被引:8,自引:0,他引:8  
赵一之 《生态学报》2005,25(12):3411-3414
确定了小叶锦鸡儿、中间锦鸡儿和柠条锦鸡儿3种植物的分布式样:小叶锦鸡儿为蒙古高原东部-F松辽平原西部-华北山地分布种,中间锦鸡儿为东戈壁-鄂尔多斯高原-黄土高原北部分布种,柠条锦鸡儿为南阿拉善-西鄂尔多斯分布种。小叶锦鸡儿适应分布于蒙古高原典型草原带和森林草原带以及华北山地落叶阔叶林带,在草原带高平原上可形成灌丛化草原的景观,在草原带的沙地上可形成以小叶锦鸡儿为建群种的沙地灌丛植被;中间锦鸡儿适应分布于蒙古高原的荒漠化草原及草原化荒漠带、鄂尔多斯高原的典型草原和荒漠化草原带的沙地及梁地上、黄土高原北部的黄土丘坡上,常形成以中间锦鸡儿为建群种的沙地灌丛植被;柠条锦鸡儿则适应分布于草原化荒漠和典型荒漠带的固定和半固定沙地上。近缘的3种锦鸡儿的地带性分布从东至西或从北向南形成明显的有规律的地理替代分布格局。  相似文献   

19.
新疆北塔山植被的初步研究   总被引:3,自引:0,他引:3       下载免费PDF全文
本文对位于中蒙边境的北塔山地区的植被类型进行了初步的研究,并在此基础上对该地区的植被与相邻地区的植被从水平地带规律性、垂直地带规律性和植物区系成分上进行了对比分析,发现北塔山的植被无论在类型上还是在区系上都具有明显的过渡性和干旱性的特征。其植被垂直带结构为荒漠、山地荒漠草原、山地灌丛草原、山地草原和嵩草高山草甸。此外还对北塔山植被的特点及草场资源利用进行了探讨。对本区的研究,有助于人们对准噶尔盆地东端的北塔山区(很少有人进行科学考察的地区)的植被有所了解,同时对该地区的草场资源的利用和野生动物的保护,均有其重要的意义。  相似文献   

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