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1.
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   

2.
The migratory routes along which the Central European species of dragonflies probably immigrated from their periglacial refuges into Central Europe are reconstructed. Due to the topographical configuration in Central Europe, the postglacial invasions were confined to only a few routes. Mountain chains and also small river valleys, i.e. the Rhine valley between Lake Constance and Waldshut, acted as barriers; while geotectonic depressions, such as the ‘Geneva Gate’, ‘Burgundian Gate’ and ‘Moravian Gate’, played an important role as ‘gateways’ in overcoming these obstacles, the wide river plains were used as corridors to invade the hinterland. The extent of the immigration into Central Europe by the dragonfly species depended on the one hand on the distances which had to be covered from the refugial areas, but, on the other hand, also on the distinct postglacial climatic periods (Preboreal, Boreal, Atlantic, Subboreal, Subatlantic). Depending on their thermal requirements each species started expanding from their refugial areas at different times. Due to variable postglacial climatic conditions, progressive migratory phases alternated with regressive phases. The very different recent distribution patterns of the Central European dragonflies can only be understood if all the climate history, landscape morphology, the thermal requirements of the species, their origin (refugial areas) and history of colonization are considered. Because many Central European dragonfly localities currently lie at the periphery of the range of many species, these species can only survive in these areas if individual ‘reinforcements’ from their centres of distribution are possible. They still take place mainly along the old routes. Thus, disruption of the migratory routes, especially at the gateways, due to anthropogenic actions may influence the fauna of large Central European regions. Due to many anthropogenic influences, the routes already often seem to be interrupted over long distances and the connections to the centre of distribution already broken. As a result of precise knowledge of the courses of the migratory routes a better prediction is possible as to whether species conservation measures or recolonization projects will be successful.  相似文献   

3.
Global climate change (GCC) is expected to lead to massive loss of global biodiversity in the alpine regions of mountain ranges. Studies on the potential effects of GCC on low mountain areas remain sparse, however, despite the high conservation value of these areas as biodiversity refugia. We chose a species distribution modeling approach to assess potential GCC impacts on the future distributions of montane freshwater invertebrates under two different greenhouse gas scenarios and three averaged general circulation models. For this, ensemble models consisting of six algorithms [generalized linear model (GLM), generalized boosted model (GBM), generalized additive model (GAM), classification tree analysis (CTA), artificial neural networks (ANN), and multivariate adaptive regression splines (MARS)] were applied to project areas of 23 cold-stenothermic aquatic insects from montane regions of Central Europe. We found an average loss of 70–80% of the potential distribution for the study species until 2080, depending on the underlying Intergovernmental Panel on Climate Change scenario. Species distribution ranges below 1000 m above sea level were found to decrease by up to ~96% according to the severest greenhouse gas emission scenario. While the Alps remain the single main refugium under the A2a greenhouse gas emission scenario, the more moderate climate scenario B2a shows fragmented potential persistence of montane insects in some low mountain ranges. The results show that montane freshwater assemblages in low mountain ranges are particularly threatened by ongoing GCC. As vertical dispersal is limited by elevational restriction, low mountain ranges may act as summit traps under GCC. We thus propose that GCC will lead to the extinction of several species and unique genetic lineages of postglacial relict species, resulting in a significant decline in Central European fauna.  相似文献   

4.
SUMMARY 1. Based on the findings that some dragonflies prefer either ‘dark’ or ‘bright’ water (as perceived by the human eye viewing downwards perpendicularly to the water surface), while others choose both types of water bodies in which to lay their eggs, the question arises: How can dragonflies distinguish a bright from a dark pond from far away, before they get sufficiently close to see it is bright or dark? 2. Our hypothesis is that certain dragonfly species may select their preferred breeding sites from a distance on the basis of the polarisation of reflected light. Is it that waters viewed from a distance can be classified on the basis of the polarisation of reflected light? 3. Therefore we measured, at an angle of view of 20° from the horizontal, the reflection‐polarisation characteristics of several ponds differing in brightness and in their dragonfly fauna. 4. We show that from a distance, at which the angle of view is 20° from the horizontal, dark water bodies cannot be distinguished from bright ones on the basis of the intensity or the angle of polarisation of reflected light. At a similar angle of view, however, dark waters reflect light with a significantly higher degree of linear polarisation than bright waters in any range of the spectrum and in any direction of view with respect to the sun. 5. Thus, the degree of polarisation of reflected light may be a visual cue for the polarisation‐sensitive dragonflies to distinguish dark and bright water bodies from far away. Future experimental studies should prove if dragonflies do indeed use this cue for habitat selection.  相似文献   

5.
三峡大老岭植物区系的垂直梯度分析   总被引:13,自引:0,他引:13  
为探讨山地植物区系构成特征及其垂直梯度的生态意义,根据对三峡大老岭地区植被垂直样带 调查获得的植物区系资料,分析了该地区植物区系成分构成的基本特征及其随海拔梯度的变化趋势,寻找了区系平衡点的位置;并利用聚类方法分析了山地气候垂直分异对区系成分构成的影响。结果表明:①大老岭植物区系具有温带性质,但仍反映了与热带区系的历史联系,有强烈的区域性;②属的分布区类型可归为热带分布、温带分布、地中海—中亚中心和东亚中心4组,各组区系成分的垂直梯度特征不同;热带、亚热带成分与温带成分的平衡点大致位于海拔650m;③区系成分构成和属的物种数量构成的聚类分析结果一致显示了植物区系构成与山地气候和植被垂直带相对应的格局。  相似文献   

6.
Long-term studies of the ground beetle fauna of Southeastern Altai (SEA) revealed 33 genera and 185 species; 3 and 15 species are reported for the first time from Russia and SEA, respectively. The following genera are the most diverse: Bembidion (47 species), Amara and Harpalus (21 each), Pterostichus (14), and Nebria (13). The subarid (35%) and boreal (32%) species prevail in the arealogical spectrum, while the mountain endemics comprise 13% of the fauna. The carabid fauna of SEA is heterogeneous in composition and differs significantly from that of the Western and Central Altai. The boreal mountain component mostly comprises tundra species with circum-boreal or circum-arctic ranges, while the subarid component (typical Mongolian together with Ancient Mediterranean species) forms more than one-half of the species diversity in the mountain basins. The species diversity increases from the nival mountain belt (15 species, predominantly Altai-Sayan endemics) to moss-lichen tundras (40, mostly boreal, species). The variety of habitats and constant hydrothermal regimes in the intrazonal valley communities determine high taxonomic diversity of Carabidae, including both tundra or meadow-steppe species typical of the region and some forest ones. Under the condition of moisture deficiency, many steppe species also concentrate in river floodplains.  相似文献   

7.
The Palaearctic flea fauna includes 921 species and 479 subspecies from 96 genera of 10 families. Of them, 858 species (94%) from 43 genera are endemic to the Palaearctic; they comprise 40% of the Palaearctic Hystrichopsyllidae, 24% of Ceratophyllidae, and 20% of Leptopsyllidae. Ranges of 581 species (63% of the Palaearctic fauna) are situated within one province or subregion of the Palaearctic. Species with ranges including a part of Asia (592) comprise 87% of the total fauna; 72% of the species (517) are endemic to the Palaearctic. The largest centers of taxonomic diversity of Palaearctic fleas are situated in the East Asian, Central Asian, and Turano-Iranian Subregions: 320 species of fleas (214 of them endemic) from 59 genera (8 endemic) are known from the East Asian Subregion; 270 species (over 120 endemic) from 54 genera (5 endemic) are distributed in the Central Asian Subregion. The Turano-Iranian fauna comprises 213 species (103 endemic) from 47 genera (3 endemic); about 160 species occur in the Turanian Subprovince closest to the Russian borders, one-third of them (52 species, or 33%) are endemic; 69 species more are endemic to the entire Asian part of the Palaearctic. Extra-Asian and extra-Siberian ranges are known in 190 flea species. In the western Palaearctic, 76 species are endemic to the European Province, and 57 species, to the Mediterranean Province; 36 species have Euro-Mediterranean distribution. The fauna of the Saharo-Arabian Subregion comprises 30 species (12 endemic), 6 species have ranges of the Mediterranean-Saharo-Arabian type. Scenarios of the origin of the Siphonaptera at the Triassic-Jurassic boundary are hypothesized. Formation of the Palaearctic flea fauna was mostly supported by the Asian-Indo-Malayan and East Asian-Western American palaeofaunal centers of taxonomic diversity. The long history of faunal exchange between the east Palaearctic and the west Nearctic is manifested by the distribution of the parasites of rodents and insectivores, fleas of the genera Stenoponia, Rhadinopsylla, Nearctopsylla, and Catallagia, belonging to several subfamilies of the Hystrichopsyllidae, as well as members of a number of other flea families. A great number of endemic species in the genera Palaeopsylla and Ctenophthalmus (Hystrichopsyllidae), both in the European and Asian parts of the Palaearctic, can be explained by the junction of the European and Asian continental platforms in the late Cretaceous and their subsequent isolation during the Paleocene. A considerable contribution to the flea fauna in the Russian territory was made by the East Asian-Nearctic center of taxonomic diversity, with a smaller role of the European palaeofauna. Immigration of species of the family Pulicidae from the Afrotropical Region is restricted to the southern territories of Russia.  相似文献   

8.
9.
Invasive alien organisms can impact adversely on indigenous biodiversity, while riparian invasive alien trees (IATs), through shading of the habitat, can be a key threat to stream invertebrates. We ask here whether stream fauna can recover when the key threat of riparian IATs is removed. Specifically, we address whether IAT invasion, and subsequent IAT removal, changes benthic macroinvertebrate and adult dragonfly assemblages, for the worse or for the better respectively. Natural riparian zones were controls. There were statistically significant differences between stream reaches with natural, IAT-infested and IAT-cleared riparian vegetation types, based on several metrics: immature macroinvertebrate taxon richness, average score per macroinvertebrate taxon (ASPT), a macroinvertebrate subset (Ephemeroptera, Plecoptera, Trichoptera and Odonata larvae; EPTO), and adult dragonfly species richness. Reaches with natural vegetation, or cleared of IATs, supported greater relative diversity of macroinvertebrates than reaches shaded by dense IATs. Greatest macroinvertebrate ASPT and EPTO were in reaches bordered by natural vegetation and those bordered by vegetation cleared of IATs, and the lowest where the riparian corridor was IATs. Highest number of adult dragonflies species was along streams cleared of dense IATs. Overall, results showed that removal of a highly invasive, dense canopy of alien trees enables recovery of aquatic biodiversity. As benthic macroinvertebrate scores and adult dragonfly species richness are correlated and additive, their combined use is recommended for river condition assessments.  相似文献   

10.
Different types of adaptations of dragonflies to climatic conditions of the desert zone are described. The main habitats of the dragonfly nymphs are lotic and semi-lotic artificial reservoirs. The life cycles are synchronous with seasonal climatic changes, reproduction being restricted to periods of the optimal hygrothermal conditions. Some species reveal vertical seasonal migrations. The labile daily activity rhythms allow the dragonflies to avoid the effects of unfavorable conditions. Adults of many species emerge at night.  相似文献   

11.
贵州茂兰自然保护区蜻蜓多样性初步研究   总被引:1,自引:0,他引:1  
2011年7月在贵州茂兰自然保护区的一些比较适合蜻蜓生长的水域附近进行了蜻蜓采集,用静观和网捕法记录采集路线两侧各20m范围内的蜻蜓,鉴定统计后分析其区系成分及多样性.结果表明:1)贵州茂兰地区现有蜻蜓65种,隶属于11科42属;2)东洋界种类较多,有31种,占总数的47.69%;古北界种类相对较少,只有1种,约占总数的1.54%;3)贵州茂兰地区蜻蜓的多样性指数为2.8617,均匀度指数为0.6855,优势度指数为0.1385,优势集中性指数为0.1006;4)5个样点之间的相似性指数均在30% ~55%之间,且只有捞村与翁昂为53.41%,捞村52.77%大于板王50%,这可能与茂兰地区生境的多样性相对较高,适宜蜻蜓生存的生境多有关.  相似文献   

12.
The butterfly fauna of the Kungey Ala-Too Mt. Range comprises 181 species, among them 58 are identified for the first time. Zoogeographic analysis of this fauna showed that a complex of butterflies with wide ranges predominated, whereas representatives of the Central Asian ranges had a smaller portion by 20%. Nowadays, the Kungey Ala-Too is a bridge between the faunas of the Western Tien Shan (Alai) and Southern Siberia.  相似文献   

13.
蜻蜓是一类营养丰富且具有药用保健价值的可食用昆虫。目前蜻蜓在国内被食用的种类见诸报道的有红蜻(Crocothemis servilia)、角突箭蜓(Gomphus cuneatus)、舟尾丝蟌(Lestes praemorsa)、闪蓝丽大蜻(Epophthalmia elegans)、碧伟蜓(Anax parthenope julius)、小团扇春蜓(Ictinogomphus rapax)、大团扇春蜓(Sinictinogomphus clavatus)、黄蜻(Pantala flavescens)、赤褐灰蜻(Orthetrum pruinosum)、白尾灰蜻(Orthetrum albistylum)、异色灰蜻(Orthetrum triangulare melania)、大黄赤蜻(Sympetrum uniforme)共12种。笔者在来自云南红河州元阳县大坪乡的待食用蜻蜓稚虫中发现一种体型较小的蜻蜓种类,从形态上初步判断不属于以上12种,通过DNA条形码分子鉴定法对这种蜻蜓进行了种类鉴定,结果该种蜻蜓为黄基赤蜻(Sympetrum speciosum),由此食用蜻蜓报道的种类又增加了一种。  相似文献   

14.
Dragonflies are good indicators of environmental health and biodiversity. Most studies addressing dragonfly ecology have focused on the importance of aquatic habitats, while the value of surrounding terrestrial habitats has often been overlooked. However, species associated with temporary aquatic habitats must persist in terrestrial environments for long periods. Little is known about the importance of terrestrial habitat patches for dragonflies, or about other factors that initiate or influence dispersal behaviour. The aim of this study was to reveal the relationship between population dynamics of the threatened dragonfly species Sympetrum depressiusculum at its natal site and its dispersal behaviour or routine movements within its terrestrial home range. We used a mark–release–recapture method (marking 2,881 adults) and exuviae collection with the Jolly–Seber model and generalized linear models to analyse seasonal and spatial patterns of routine movement in a heterogeneous Central European landscape. Our results show that utilisation of terrestrial habitat patches by adult dragonflies is not random and may be relatively long term (approximately 3 mo). Adult dragonflies were present only in areas with dense vegetation that provided sufficient resources; the insects were absent from active agricultural patches (p = 0.019). These findings demonstrate that even a species tightly linked to its natal site utilises an area that is several orders of magnitude larger than the natal site. Therefore, negative trends in the occurrence of various dragonfly species may be associated not only with disturbances to their aquatic habitats, but also with changes in the surrounding terrestrial landscape.  相似文献   

15.
Using DNA barcoding and stable isotope analysis, we identified adult dragonfly prey items from the fecal pellets of five dragonfly species—Nannophya pygmaea, Ischnura asiatica, Sympetrum eroticum, Orthetrum albistylum, and Anax parthenope—collected from a mountain bog located in south‐eastern South Korea. Twelve operational taxonomic units (OTUs) belonging to four orders, Coleoptera, Diptera, Hemiptera, and Lepidoptera, were identified as prey items of adult dragonflies using DNA barcoding. Among prey items, Dipterans were the most common, comprising seven of the 10 OTUs. Based on stable isotope analysis, adult dragonflies and their nymphs were among the most numerous predators in both aquatic and terrestrial habitats. Additionally, dragonfly species with smaller adult sizes had different isotopic compositions to those reaching larger adult sizes. Both δ15N and δ13C values were significantly lower in smaller species than in larger species, indicating differences in their trophic levels and carbon sources.  相似文献   

16.
江西武夷山自然保护区蝶类区系结构及垂直分布   总被引:17,自引:0,他引:17  
丁冬荪 《昆虫学报》1996,39(4):393-407
据有较详细分布资料的227种蝶类昆虫分析,武夷山蝶类属东洋界范畴;垂直分布研究结果表明,武夷山蝶类从山麓至山顶,随着海拔升高,东洋界种类递减,古北界成分逐渐增多,尤以海拔1100m以上更加明显;在海拔1800m以上东洋界种被古北及古北跨区系种所替代。本文对武夷山蝶类水平分布的南北限和垂直分布的上限及它们的相互关系作了探讨。  相似文献   

17.
新疆东部天山蝶类多样性及其垂直分布   总被引:5,自引:0,他引:5  
张鑫  胡红英  吕昭智 《生态学报》2013,33(17):5329-5338
2006-2008年研究了新疆东部天山蝶类多样性和垂直分布.结果表明:研究区域内共记录蝴蝶7科43属63种,占新疆已记录蝶类种数的24.80%,区系组成主要是古北种,占73%;其次是广布种,占27%,没有发现东洋种.其中蛱蝶科的物种数最多,为11属19种,蚬蝶科的物种数最少,只有1属1种.按海拔将生境分为5个垂直自然带,包括低山灌木草原带、山地森林草原带、亚高山草甸带、高山草甸带、垫状植被带.蝶类物种数和个体数排序为亚高山草甸带>山地森林草原带>低山灌木草原带>高山草甸带>垫状植被带.采用Shannon-Wiener指数和G-F指数对蝶类物种和科、属的多样性进行了分析评价,结果显示亚高山草甸带的蝶类多样性最为丰富,其次是山地森林草原带和低山灌木草原带,而高山草甸带和垫状植被带的蝶类多样性相对较低,物种和科、属多样性分析结果均一致.蝶类垂直分布明显,物种数和个体数随海拔变化的趋势类似,均为先增加后下降.蝶类区系成分随着海拔升高发生改变,广布种的比例逐渐降低,高山草甸带和垫状植被带只有古北种分布.研究结果显示,生境改变对蝴蝶群落影响明显,保护生境是保护蝴蝶生存的最主要措施.  相似文献   

18.
The odonate larval communities in three small rivers in Penang Island were studied. More species of dragonflies were found in the Botanical Garden and Titi Teras rivers (13 and 11 respectively) of relatively similar environmental parameters. Fewer (nine) dragonfly species were collected from the Youth Park River which has a lower dissolved oxygen (DO) and a higher biological oxygen demand (BOD), conductivity and turbidity. A mixture of sand, gravel and pebble substrate of Botanical Garden River with dense growth of submerged Hydrilla, grasses and Cladias (Araceae) provided suitable habitats for the dragonflies. The sandy substrate and relatively fast flowing water of Titi Teras River was highly preferred by gomphids. In the Youth Park River, the small community of dragonfly larvae was dominated by tolerant Pseudagrion rubriceps, P. microcephalum, Orthetrum chrysis and Crocothemis servilia. Based on the larval instar distribution of Ictinogomphus decoratus and O. chrysis, very asynchronous populations of these dragonflies occurred in each river. Young larvae were continuously introduced into the populations resulting in undulating growth rate curves. The growth rates of these two species were higher in the Titi Teras River when compared to those in other rivers. Density-dependent mortality, asynchronous cannibalism and fish predation could play important roles in regulating the larval dragonfly population in these rivers.  相似文献   

19.
Carotenoids of 20 species of dragonflies (including 14 species of Anisoptera and six species of Zygoptera) were investigated from the viewpoints of comparative biochemistry and chemical ecology. In larvae, β-carotene, β-cryptoxanthin, lutein, and fucoxanthin were found to be major carotenoids in both Anisoptera and Zygoptera. These carotenoids were assumed to have originated from aquatic insects, water fleas, tadpoles, and small fish, which dragonfly larvae feed on. Furthermore, β-caroten-2-ol and echinenone were also found in all species of larvae investigated. In adult dragonflies, β-carotene was found to be a major carotenoid along with lutein, zeaxanthin, β-caroten-2-ol, and echinenone in both Anisoptera and Zygoptera. On the other hand, unique carotenoids, β-zeacarotene, β,ψ-carotene (γ-carotene), torulene, β,γ-carotene, and γ,γ-carotene, were present in both Anisoptera and Zygoptera dragonflies. These carotenoids were not found in larvae. Food chain studies of dragonflies suggested that these carotenoids originated from aphids, and/or possibly from aphidophagous ladybird beetles and spiders, which dragonflies feed on. Lutein and zeaxanthin in adult dragonflies were also assumed to have originated from flying insects they feed on, such as flies, mosquitoes, butterflies, moths, and planthoppers, as well as spiders. β-Caroten-2-ol and echinenone were found in both dragonfly adults and larvae. They were assumed to be metabolites of β-carotene in dragonflies themselves. Carotenoids of dragonflies well reflect the food chain during their lifecycle.  相似文献   

20.
《Flora》2005,200(4):376-397
World distribution of 488 out of 619 vascular plant species known from an area of 500 km2 within the western Khentey Mountains, northern Mongolia is analyzed. Most species belong to Eastern Asian (29%) or Asian, Eurasian, or circumpolar temperate species (24%) supporting the classification of the Khentey Mountains as part of the temperate zone of Eurasia. Seventeen percent of species are boreal plants. Circumpolar temperate-boreal (9%), Central (-Eastern) Asian (9%), Continental mountain species (5%), Middle-Central Asian (3%), arctic-alpine (3%) as well as Western Eurasian and western Siberian species are of lower significance for the flora of the western Khentey Mountains. Eastern Asian species occur in all types of habitats, whereas plants of other distribution types are focused on certain habitats. Boreal species preferably grow in the dark taiga, which prevails in the upper montane belt and on northern and eastern slopes of the most humid parts of the lower montane belt. Temperate and temperate-boreal species prefer subtaiga forests, which are found on northern and eastern slopes in drier parts of the lower montane belt as well as in upper parts of sun-exposed, southern and western slopes of the lower montane belt. Central (-Eastern) Asian and Middle-Central Asian species primarily inhabit forest steppe habitats, such as meadow and mountain steppes, Ulmus pumila open woodlands and dry Pinus sylvestris forests on steep, southern slopes.  相似文献   

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