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1.
以分布于新疆北部古尔班通古特沙漠南缘的12种短命植物为研究材料,采用常规石蜡切片法,对其叶的解剖结构进行了观察分析,探讨12种短命植物的叶解剖结构对荒漠生态环境的适应性关系。结果显示:(1)12种短命植物中,有8种植物的叶肉栅栏组织发达,表现出等面叶特征;有7种植物侧脉维管束具有花环状结构,表现出C4植物特点。(2)12种植物叶片均具有气孔下室,其中,小花荆芥等7种植物叶片具有发达的气孔下室。(3)12种植物叶肉及叶脉中常有晶体存在,晶体数量及大小在不同植物中有差异。研究认为,12种短命植物从总体上呈现出旱生结构特征,从个体角度看这些特征是不同类群的植物以不同方式适应沙漠干旱环境的结果,但不足以改变该类植物的中生性质。  相似文献   

2.
新疆的短命植物(三)群落学意义和资源价值   总被引:3,自引:0,他引:3  
在中亚西部荒漠亚区,短命植物种类丰富(乌兹别克斯坦即有250种之多),且发育繁茂。由其所形成的草群,外貌状若草甸、草原或荒漠,曾被一些早期的地植物学家描述为不同的植物群落类型。我国的植物学工作者,对局部地段或小生境中群集生长的短命植物草被现象,常称之为“小群落”或“群聚现象”,在文献中也从不使用短命荒漠、短命草甸、萨旺纳或半萨旺纳等植物群落类型的名称。新疆的短命植物总是或多或少地出现在某些植物群落之中,所以我们更加强调它的群落学意义。在新疆北部的莫索湾沙区,短命植物种类占白梭梭群落全部种类组成的…  相似文献   

3.
新疆莫索湾地区短命植物的初步研究   总被引:20,自引:2,他引:20       下载免费PDF全文
莫索湾地区位于准噶尔盆地西南部主要由固定、半固定以及半流动的沙丘、沙地组成,是古尔班通古特沙漠的组成部分。是典型的温带荒漠气候,代表性植被是小半乔木荒漠。在这种严酷的大陆性荒漠气候条件下,由下列原因使短命植物得以发育;1.年降水量虽少,但冬有积雪,春有一定降雨,为短命植物的发育提供了有利的水分条件;2.基质为疏松沙层,毛细管作用微弱,在少雨干旱的环境中,具有一定的保水特性。春季至夏初间,湿沙层的存在为具浅根系的短命植物整个生长发育期间提供了十分有利的水分供应;3.虽然冬严寒,夏炎热,但春季和暖。其热量状况可满足短命植物进行高效光合生产的需要,尤其是较大的日温差,对光合产物的积累非常有利。莫索湾地区共有短命植物42种,分属于38属,16科。其生活型组成有短营养期多年生和短营养期一年生植物两大类群,根据繁殖特点和地下器官的形态特征等生态生物学特点进一步细分为7类。本区短命植物是两种梭梭群落的重要成员,盖度很大,在春季产量结构中占有重要地位,起着明显的层片作用。另外,在莫索湾地区短命植物常以植物群聚形式出现在裸露基质上,构成群落发展的先锋阶段。  相似文献   

4.
本研究对内蒙古荒漠药用植物资源进行统计分析,以期为药用植物资源开发利用提供一定的理论依据,通过野外调查结合相关文献整理,分析药用植物资源特征。结果表明:内蒙古荒漠药用种子植物有66科190属285种,大多是草本和灌木,以中生类型为主,旱生与湿生类型均有存在,生态幅度较为广,同时具有明显的荒漠特征。不同的生活型与生态水分类型在功能类型上主要发挥清热的功效,同时存在一定的差异。药用植物资源在药用性能及药用部位表现为多样性,具有一定的开发潜力;从药性分析,以寒性为主;从药味分析苦味药、甘味药及辛味药是主要组成部分;从功能类型分析,可划分成19类,主要发挥清热的功效。药用植物资源用途多样性,有极大的经济价值,包括重点药用植物5种,濒危保护植物15种。建议加强对药用植物的科学研究,加大对药用植物的监管保护力度,合理开发荒漠药用植物资源,促进荒漠产业发展。  相似文献   

5.
新疆准噶尔盆地拥有世界温带荒漠中最为丰富的野生动植物资源。但由于长期以来过度放牧、开垦、樵采、滥挖、盗猎等人类活动的干扰, 以及目前石油、煤炭等矿产资源的开发, 准噶尔盆地的生物多样性岌岌可危, 迫切需要提出生物多样性保育计划来解决开发与保护之间的矛盾。本文首先从荒漠植被类型、短命植物资源、野生动物资源等几个方面详尽地分析了准噶尔盆地生物多样性的现状, 提出了准噶尔盆地生物多样性保育的重点是: (1)盆地腹地的以梭梭(Haloxylon ammodendron)、白梭梭(H. persicum)等为代表的温带矮半乔木荒漠, 以沙拐枣(Calligonum spp.)、柽柳(Tamarix spp.)等为代表的灌木荒漠, 及以猪毛菜(Salsola arbuscula)、假木贼(Anabasis spp.)为代表的半灌木和矮半灌木荒漠等3种荒漠植被类型; (2) 短命植物资源; (3) 以普氏野马(Equus przewalskii)为代表的野生有蹄类动物; 然后结合准噶尔盆地煤和石油等矿产资源的分布和开发的重点地区, 目前保护区现状以及国外相关的保护经验, 论证了准噶尔盆地生物多样性保育的可行性。基于以上分析, 我们从规划布局以及立法、管理体制、旅游资源管理等方面提出了建立准噶尔国家荒漠公园的构想。  相似文献   

6.
中国的几种植被类型(Ⅳ) 温带荒漠与荒漠生态系统   总被引:1,自引:0,他引:1  
温带荒漠分布于偏离亚热带“回归荒漠带”的中高纬度地带。我国与中亚西部的荒漠为地球上最广大的一片温带荒漠。其气候特点除了降水量很低和潜在蒸发力很强等典型荒漠特点外,还以具有寒冷的冬季为特点。因此,其中没有常绿的仙人掌类肉质植物,以叶强度退化的小乔木、灌木和半灌木为代表的生活型;在冬春较湿润的中亚西部荒漠中,尚有丰富的春季短生植物。荒漠生态系统中一切能量转换与物质循环均受制于水分在系统中的运转;由于水分的缺乏,其中的生物活动十分微弱,环境的物理作用则常在系统中占优势。由于系统中各成分间的不平衡,导致了系统的相对脆弱,易于遭到破坏而难以恢复,即所谓的“荒漠退化”。但在局部有较充足水分保证和森林防护的地段,则可形成天然或人工的绿洲。温带荒漠本身含有有价值的生物资源,在合理保护与开发下也可发挥其应有的生产潜力。  相似文献   

7.
在野外实地调查和室内标本整理鉴定的基础上,对石河子绿洲-荒漠区菊科植物物种多样性进行了初步研究。结果表明:(1)石河子绿洲-荒漠区菊科植物(不包括栽培)有45属90种,其中菊苣族、飞廉族、春黄菊族较多,共30属(占总属数的66.7%),67种(占总种数的74.4%);而且单种属和寡种属在该区菊科区系中占有很大比例,共42属(占总属数的99.33%),70种(占总种数的77.78%)。(2)该区菊科植物属的地理成分可划分为8个类型和5个变型,以旧世界温带及其变型成分(35.90%)与地中海区、西亚至中亚成分(28.21%)为主。(3)该区菊科植物生活型有5个类型,以一、二年生植物(27.78%)和地面芽植物(40%)为主,且短命(16.67%)、类短命(8.89%)、地上芽(6.67%)植物也为重要组成者;其生境较为多样,且各生境间相互渗透密切相关。  相似文献   

8.
短命植物条叶车前的小孢子发生与雄配子体发育的研究谭敦炎,田允温,艾合买提(新疆八一农学院,乌鲁木齐830052)条叶车前(Plantagolessingii)为新疆北部蒿属荒漠上广泛分布的一种典型的寿雨型早春短命植物,每年4月初种子开始萌发,并迅速生...  相似文献   

9.
古尔班通古特沙漠南部植物多样性的区域差异   总被引:1,自引:0,他引:1  
罗宁  刘尊驰  于航  刘彤 《生态学报》2016,36(12):3572-3581
植物多样性分布受环境影响,具有尺度依赖性,研究不同区域植物多样性的差异和分布规律有助于剖析群落多样性的整体形成和变化原因,进而为实施有效的保护和利用提供科学依据。以古尔班通古特沙漠植物多样性集中分布的南部为研究区,沿经向方向划分3条样带(绿洲边缘样带、克拉玛依至吉木萨尔的沙漠公路样带以及距离二者之间的沙漠腹地样带),同时根据沙垄高度、走向和生境差异将研究区划分为5个分区,对比研究各样带、各分区的α、β多样性特征及物种共性和差异性。结果表明:3条样带的α多样性变化为绿洲边缘样带沙漠公路样带沙漠腹地样带。随经度的增加,各样带的物种相似性和替代性特征表现相似的变化趋势。物种分析发现沙漠公路样带内短命植物分布较多,绿洲边缘样带以多年生草本和灌木群落为主,而沙漠腹地样带介于二者之间。各分区间的物种组成存在一定差异。沙漠西部、东部、莫索湾垦区附近、沙漠腹地等分区物种丰富度均较高,而古玛纳斯湖区的植物丰富度较低,与其余4个分区间的物种相似性小,相互替代性较强。总结认为古尔班通古特沙漠南部各分区间植物多样性受地史过程的影响较大,而样带间植物多样性受土壤质地、降水量等环境因素影响较大;沙漠东部似是整个南部沙漠的物种扩散中心。  相似文献   

10.
丛欣欣  曹伟  王金菊 《生态科学》2011,30(5):525-530
调查和分析了白石砬子保护区早春类短命植物物种组成的数量特征,应用物种丰富度指数、Shannon-Wiener多样性指数、Pielou均匀度指数、Simpson优势度指数,定量描述了不同林型下早春类短命植物的物种多样性.结果表明:研究区有早春类短命植物12种2变型,隶属7科11属.黑水银莲花是早春类短命植物层片的优势种.花曲柳林下早春类短命植物物种数最多,枫桦林、红松阔叶林、落叶松林次之,蒙古栎林、杂木林、鱼鳞云杉臭冷杉林最少.多样性指数的变化趋势总体上表现为针阔混交林>落叶阔叶林>针叶林.均匀度指数的变化与多样性指数的变化趋势基本一致,与优势度指数的变化趋势相反.红松阔叶林下早春类短命植物物种多样性最高且各物种均匀分布,层片结构稳定.  相似文献   

11.
Aim We compared assemblages of small mammal communities from three major desert regions on two continents in the northern hemisphere. Our objective was to compare these with respect to three characteristics: (1) species richness and representation of trophic groups; (2) the degree to which these assemblages exhibit nested community structure; and (3) the extent to which competitive interactions appear to influence local community assembly. Location We studied small mammal communities from the deserts of North America (N=201 sites) and two regions in Central Asia (the Gobi Desert (N=97 sites) and the Turan Desert Region (N=36 sites), including the Kara-Kum, Kyzyl-Kum, NE Daghestan, and extreme western Kazakhstan Deserts). Method To provide baseline data we characterized each desert region in terms of alpha, beta, and gamma diversity, and in terms of the distribution of taxa across trophic and locomotory groups. We evaluated nestedness of these communities using the Nestedness Temperature Calculator developed by Atmar & Patterson (1993, 1995) , and we evaluated the role of competitive interactions in community assembly and applied a null model of local assembly under varying degrees of competitive interaction ( Kelt et al., 1995, 1996 ). Results All three desert regions have low alpha diversity and high beta diversity. The total number of species in each region varied, being highest in North America, and lowest in the Turan Desert Region. The deserts studied all present evidence of significant nestedness, but the mechanism underlying this structure appears different in North American and Asia. In North America, simulations strongly implicate interspecific competition as a dominant mechanism influencing community and assemblage structure. In contrast, data from Asian desert rodent communities suggest that these are not strongly influenced by competition; in fact, they have greater numbers of ecologically and morphologically similar species than expected. These results appear to reflect strong habitat selection, with positive associations among species that share similar habitat requirements in these communities. Our analyses support earlier reports suggesting that predation and abiotic forces may have greater influences on the assembly and organization of Asian desert rodent communities, whereas interspecific competition dominates assembly processes in North America. Additionally, we suggest that structuring mechanisms may be very different among the two Asian deserts studied. Gobi assemblages appear structured by trophic and locomotory strategies. In contrast, Turan Desert Region assemblages appear to be randomly structured with respect to locomotory strategies. When trophic and locomotory categories are combined, however, Turan species are positively and nonrandomly associated. Main conclusions Very different ecological dynamics evidently exist not only between these continents, but within them as well. These small mammal faunas differ greatly in terms of community structure, but also appear to differ in the underlying mechanisms by which communities are assembled. The underlying role of history and geography are strongly implicated as central features in understanding the evolution of mammalian faunas in different deserts of the world.  相似文献   

12.
增加降水对荒漠短命植物当年牧草生长及群落结构的影响   总被引:7,自引:1,他引:6  
孙羽  张涛  田长彦  李晓林  冯固 《生态学报》2009,29(4):1859-1868
通过模拟降水增加试验研究了古尔班通古特荒漠常见短命植物盖度、密度及产量对水分输入量增加的响应.结果表明:尖喙牻牛儿苗、弯果胡卢巴、角果藜、琉苞菊、条叶庭芥及囊果苔草6种牧草生物量总和占总生物量的60%以上,是荒漠草原的优势牧草植物;供水量增加显著促进了角果藜、尖喙牻牛儿苗、弯果胡卢巴、条叶庭芥和琉苞菊5种牧草植物的个体生长;在自然降水的基础上,增加40mm和80mm供水使这5种植物生物产量比对照增加86%~230%.供水增加后,6种重要牧草对整个群落的生物贡献比例发生很大变化,只有角果藜和尖喙牻牛儿苗的贡献比例规律性增加,分别比对照增加了58%和11%,表明2种植物对供水增加的环境变化适应能力强;供水量增加促进了弯果胡芦巴、尖喙牻牛儿苗和角果藜3种植物N、P和K养分的吸收量;与此同时,供水量增加也显著提高了荒漠短命植物的密度和盖度.在降水增加的背景下,古尔班通古特沙漠南缘荒漠短命植物群落结构发生改变,植被盖度和群落净初级生产力提高,这对于防风固沙、稳定沙面,增加荒漠草原载畜能力有着积极的意义.  相似文献   

13.
阿拉善荒漠区一年生植物层片物种多样性及其分布特征   总被引:17,自引:0,他引:17  
一年生植物层片是阿拉善荒漠区荒漠与绿洲生态系统的恒有植物层片,对荒漠生态系统的稳定和当地畜牧业的生产都有重要作用.对该层片的物种多样性及其在群落中的分布特征分析表明,荒漠与绿洲生态系统中,一年生植物层片植物种有12科35属61种,可归为一年生小禾草、一年生猪毛菜、一年生蒿类和一年生杂类草4个类群,并可划分成12种区系地理成分,其中有10个阿拉善或近阿拉善特有种.一年生植物层片广泛分布于土质、沙砾质、沙质、砾质、石质、盐土荒漠及各种类型的绿洲群落中,常一种或几种组成层片,均匀或斑块状分布,或沿水线分布.此外,还分析和评价了一年生植物层片在群落中的分布差异、生态适应模式与功能.  相似文献   

14.
Aims Deserts are one of the ecosystems most sensitive to global climate change. However, there are few studies examining how changing abiotic and biotic factors under climate change will affect plant species diversity in the temperate deserts of Asia. This study aimed to: (i) characterize species distributions and diversity patterns in an Asian temperate desert; and (ii) to quantify the effects of spatial and environment variables on plant species diversity.Methods We surveyed 61 sites to examine the relationship between plant species diversity and several spatial/environmental variables in the Gurbantunggut Desert. Spatial and environmental variables were used to predict plant species diversity in separate multiple regression and ordination models. Variation in species responses to spatial and environmental conditions was partitioned by combining these variables in a redundancy analysis (RDA) and by creating multivariate regression trees (MRT).Important findings We found 92 plant species across the 61 sites. Elevation and geographic location were the dominant environmental factors underlying variation in site species richness. A RDA indicated that 93% of the variance in the species–environment relationships was explained by altitude, latitude, longitude, precipitation and slope position. Precipitation and topographic heterogeneity, through their effects on water availability, were more important than soil chemistry in determining the distribution of species. MRT analyses categorized communities into four groups based on latitude, soil pH and elevation, explaining 42.3% of the standardized species variance. Soil pH strongly influenced community composition within homogeneous geographic areas. Our findings suggest that precipitation and topographic heterogeneity, rather than edaphic heterogeneity, are more closely correlated to the number of species and their distributions in the temperate desert.  相似文献   

15.
Global climate change is one of the most pressing conservation challenges; in particular, changes in precipitation regimes have already substantially influenced terrestrial ecosystems. However, the mechanisms influencing precipitation changes on individual plants and the plant communities in desert grasslands have yet to be fully elucidated. We therefore examine the influence of increased precipitation on plant community compositions in the Gurbantunggut Desert, Xinjiang, northwestern China, from 2005 to 2009. We found that growth of all plant species and the community productivities increased markedly with enhanced water input. Cover of ephemeral synusia also significantly increased due to increased precipitation, implying that the role of the ephemeral community for stabilization of sand dunes was strengthened by increased precipitation. The response of plant community compositions to increased precipitation was primarily reflected as changes in plant density, while increased precipitation did not affect plant species richness and the diversity index. Dominant species drove the response of plant density to increasing precipitation during the five‐year study period. However, the relative responses of rare species were stronger than those of the dominant species, thereby potentially driving species turnover with long‐term increased precipitation. This finding improved our understanding of how increased precipitation drives the changes in plant community composition in desert grasslands and will help to better predict changes in the community composition of ephemerals under future global climate change scenarios.  相似文献   

16.
新疆准噶尔荒漠短命植物群落特征及其水热适应性   总被引:4,自引:0,他引:4  
短命植物是一类利用短暂湿季快速生长的特殊植物类群, 包括一年生短命植物和类短命植物。作者在新疆北部准噶尔荒漠的莫索湾地区从2005-2008年进行了连续4年的群落调查研究, 通过25条样线201个样方的调查, 并结合同时段冬春季节的气温、降水资料, 探讨了短命植物对环境水热变化的适应性特征。结果表明: (1) 早春季节, 短命植物在准噶尔荒漠植物群落组成中占据优势地位, 物种数均占调查总物种数的52%左右; (2) 从群落优势种来看, 7种植物标准频度在40%以上, 其中6种是短命植物, 分别是旱麦草(Eremopyrum orientale)、卷果涩芥(Malcolmia scorpioides)、硬萼软紫草(Arnebia decumbens)、狭果鹤虱(Lappula semiglabra)、四齿芥(Tetracme quadricornis)和沙滨藜(Atriplex dimorphostegia); (3) 群落中短命植物萌发的个体数量与前一年冬季温度关系极为密切, 较低的冬季温度更易激发其萌发, 而当年群落外貌特征则更多地依赖于早春季节的降水, 若早春季节温度过低也会影响短命植物的萌发; (4) Shannon-Wiener多样性指数和Pielou均匀度指数年际间变化趋势与同期冬春降水总量变化趋势一致。总之, 温度和降水的不同配置是引起短命植物多样性发生年际变化的主要因素。  相似文献   

17.
Central Asian area above 2000 m was studied to test the independence of the Central Asian Mountain region in the herpetogeographical map of the Palearctic Region and the neighboring Sahara-Gobi Desert region. According to the range and origin similarity, all species inhabiting this area were assigned to several groups: mountain Central Asian species (the bulk of the range lies within the studied area), Western Asian upland species (the bulk of the range lies in the Near Eastern uplands), plain desert species (the bulk of the range is below 2000 m), Indo-Malayan species (the bulk of the range lies within the Indo-Malayan Kingdom), European species (the bulk of the range lies in the forest and steppe zones of Europe and West Siberia), and mountain desert species (equal parts of the range lie in the deserts and mountains of Central Asia). The distribution of species density was mapped by range superposition for each group. The dominance (over 50% of the total number of species) of mountain Central Asian or other species groups allowed us to assign the studied area to either the Central Asian mountain region or Sahara-Gobi desert region. The areas where neither of the specified groups exceeded the 50% threshold were recognized as transitional. Considering a large number of endemic species (28% of the total fauna), the Central Asian mountain area should be recognized as an independent region rather than a subregion of the Sahara-Gobi Desert region.  相似文献   

18.
古尔班通古特沙漠南部植物多样性及群落分类   总被引:4,自引:0,他引:4  
张荣  刘彤 《生态学报》2012,32(19):6056-6066
采用分层取样的方法,以1000m2/样地为最小观测面积,对古尔班通古特沙漠南部61样地植物多样性进行了调查。发现92个物种,隶属于22科71属,单种科、单种属多,区系优势现象明显。草本植物占总物种数的81.5%,短命植物占43.5%,对物种丰富度和盖度的空间变化起决定作用。属的区系成分分析表明地中海、西亚至中亚分布型成分占大多数,具有典型的地中海旱生植物区系分布特征。总物种数,草本物种数,短命植物物种数与纬度显著负相关,与经度和海拔显著正相关。从南到北,总盖度、草本盖度和短命植物的盖度显著下降,灌木的盖度则增加,从西到东,总盖度、草本盖度和短命植物的盖度显著增加,而灌木的盖度则减少。采用多元回归树(Multivariate regression trees,MRT)方法,根据纬度、土壤pH值和海拔,将61样地分为4个群落。结合降水在古尔班通古特沙漠由西到东,由南到北梯度变化所导致的物种多样性的变化,推测如果未来降水持续增加,古尔班通古特沙漠草本植物的优势将更加明显。  相似文献   

19.
位于北疆准噶尔盆地中部的古尔班通古特沙漠,其植物区系和植被居于亚洲中部荒漠和哈萨克斯坦荒漠之间的过渡,但本身具有自己的特点。沙地植被主要由9个群落和3个群聚组成。由于各部分的自然条件、区系和群落性质的差别,沙漠本身在植被上又分异成三个不同的部分:西南区、东南区和北部区。在亚洲荒漠的详细划分方案中,包括古尔班通古特沙漠在内的准噶尔盆地荒漠可以作为独立的植物地理区划分出来。  相似文献   

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