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1.
Little has been published to describe or interpret Asian biodiversity hotspots, including those in the East Himalayan Mountains of Southwest China (HMSC), thus making necessary a review of the current knowledge. The Pliocene and Pleistocene geological and glacial histories of the Asian continent differ from those of Europe and North America, suggesting different mechanisms of speciation and extinction, and, thus, different responses to climate changes during the Quaternary glaciations. This short review summarizes potential drivers in shaping and maintaining high species richness and endemism of birds in the HMSC. The geographical location at the junction of different biogeographical realms, the wide range of habitats and climates along the extensive elevational range, the complex topography and the distinct geological history of this region have probably contributed to the evolution of an exceptionally species‐rich and endemic‐rich, specialized montane avian fauna. The Mountain systems in the HMSC may have provided refugia where species survived during the glacial periods and barriers for preventing species dispersal after the glacial periods. More studies are required to further test this refugia hypothesis by comparing more cold‐tolerent and warm‐tolerent species.  相似文献   
2.
Summary Cucumis sativus var. hardwickii (Royle) Alef., the wild progenitor of cultivated C. sativus is reported for the first time from peninsular India. The South Indian specimens showed n=7 bivalents in PMCs. The discontinous occurrence of the wild taxon in the Himalayan regions and peninsular hills and the existence of cultivars of C. sativus adapted to the tropical and temperate climates suggest polytopic domestication of the cultivated forms. The possibility of utilizing this wild germplasm for crop improvement is indicated.  相似文献   
3.
徐明旺 《林业调查规划》2020,45(3):54-59,157
为对泸沽湖省级自然保护区的生物多样性及环境质量做出更好的评估,分别于2016年3月,6月,7月就其鱼类资源特点及其分布格局等开展了3次调查。结果表明,泸沽湖省级自然保护区记录鱼类6目8科15属17种,鲤形目鲤科鱼类种数最为丰富,共9种,占泸沽湖鱼类总种数的52.9%;土著鱼类仅2属4种,分别为泥鳅、厚唇裂腹鱼、宁蒗裂腹鱼、小口裂腹鱼。区系组成与云贵高原湖泊存在共同特点:种类贫乏,个体较小,生长稍慢。泸沽湖鱼类物种多样性匮乏、物种同域分化现象明显、鱼类特有性极强、物种群落脆弱性极高、物种组成自然性偏低。文中提出保护好鱼类产卵场,加强入湖河流的清淤治理,建立保育繁殖基地等保护策略。  相似文献   
4.
【目的】分析小叶蝉亚科昆虫在中国动物地理各区、亚区的分布情况,探讨小叶蝉亚科分布格局形成的原因。【方法】根据中国动物地理区划,基于现有标本及相关文献,建立小叶蝉亚科昆虫在中国的分布区/属、分布亚区/属矩阵,并用PAUP4.0进行启发式搜索得到分布区支序图,用SPSS17.0软件对有小叶蝉亚科分布的亚区进行聚类分析。【结果】中国小叶蝉亚科昆虫分布区形成的顺序首先为东北区、青藏区,然后是蒙新区和华北区,最后是西南区、华中区及华南区;华北区2个亚区与东洋区分布的小叶蝉及滇南山地亚区与西南山地亚区分布的小叶蝉相似性程度均较高。【结论】小叶蝉亚科昆虫动物地理分布区形成的先后顺序可能与第四纪冰期活动有关;华北区的黄淮平原亚区、黄土高原亚区分布的小叶蝉与东洋区的相似性较高,这可能与华北区是物种由南向北扩散的过渡区有关。  相似文献   
5.
The study of several arthropod groups in high endemism areas (HEA) of Algarve, the Southernmost province of Portugal, has revealed endemic species and species not yet recorded for the Portuguese fauna. The list includes 3 species of Isopoda endemic to Algarve, to Portugal or to the Iberian Peninsula, 2 species new to Portugal and 2 species new to the Iberian Peninsula; 2 species of Pseudoscorpiones not yet cited to Portugal; 11 species of Pauropoda new to Portugal, including one new species probably endemic; 15 species of Collembola endemic to the Portuguese or to the Iberian Peninsula faunas (Gama et al. 1997) and 37 species and 5 subspecies of Staphylinidae endemic to Algarve.With the exception of Collembola, which have been studied by us, the remaining groups have been submitted for study to several specialists.These findings heighten the biological richness of these areas of high endemism in terms of conservation of biological diversity. The authors draw attention to the necessity to preserve or restore the biological value of these areas, encouraging the adoption of protective measures and the creation of research programmes that include the implementation of taxonomic studies and co-operation between taxonomists and ecologists in order to preserve the biodiversity of these areas.  相似文献   
6.
The collembological composition of samples from the Central and Western Pyrenees (Northern Spain) was studied. Soils from two biotopes (pine forest and Rhododendron shrub) were studied in Nuria and Vallibierna, using different diversity indices and multivariate analyses. Ten species were found that were endemic to the Iberian Peninsula. Three of these are exclusive to the Pyrenees: Ceratophysella elegans, Hypogastrura dasiensis and Protachorutes pyrenaeus. The greatest diversity was observed in the soils of Rhododendron, above all at Nuria. Collembola were most poorly represented in the pine forest of Vallibierna, where the endemic Hypogastrura meridionalis was the dominant species. Multivariate analyses indicated that the latter species characterizes this pine forest and separates it from all other biotopes studied. The evenness (E) was most pronounced in Nuria, where Folsomia manolachei was the characteristic species.  相似文献   
7.
China lies at the heart of the global center of freshwater crab diversity in tropical Asia, where the 2 most diverse families occur: Potamidae (505 species, 95 genera) and Gecarcinucidae (344 species, 59 genera). China stands out as the country with the highest species richness of freshwater crabs globally. Its fauna comprises 243 species in 37 genera and in 2 families, and species discovery is still progressing at a rapid pace. The vast majority of the species are distributed in southwest, south central and eastern China in the Oriental zoogeographical region. China also stands out as having a highly endemic freshwater crab fauna at the species level (96%) and at the genus level (78%). Although the recent International Union for the Conservation of Nature (IUCN) red list conservation assessment found only 6 out of 228 species (2%) to be threatened (5 potamids and 1 gecarcinucid), the majority (more than 75%) of Chinese species are regarded as data deficient, so the number of threatened species is likely to be a serious underestimate. Threats from increasing habitat destruction and pollution are a major concern due to the rapidly growing economy and massive developments taking place in China. There is therefore an urgent need for increased species exploration and for the development of a conservation strategy for China's threatened (and potentially threatened) endemic freshwater crab species.  相似文献   
8.
Abstract

The distribution of Phyllostachys pubescens, introduced to Japan from China in 1736, has been expanding. The expansion was studied in Tanabe Town, Kyoto Pref., Central Japan. Long term expansion was traced using a topographic map, a land-use map and aerial photographs. Within the research region (21.35 km2), the number and total area of bamboo sites increased from 24 and 0.16 km2 in 1953 to 174 and 3.04 km2 in 1985. By contrast, the total area of tree sites decreased from 12.2 km2 in 1953 to 8.5 km2 in 1985. The average area of bamboo sites also increased from 0.67 ha in 1953 to 1.75 ha in 1985. The average rates of the current expansion, measured by censusing current and old culms in the front of 10 unmanaged bamboo sites, were 2.1 m yr-1. Stand structure was detailed in a transitional area from a pure stand of P. pubescensto a mixed broadleaved forest. Stand structure was simpler in the area dominated by P. pubescens.Culms off! pubescenswere larger in the pure stand, and variations in DBH and height were smaller for the bamboo than for the trees in each sample site. P. pubescenshad a greater average crown length and higher canopy position. These traits allow P. pubescensto invade adjacent forests, form a uniform monolayer of foliage, and dominate competing vegetation. There was no evidence of seedling regeneration under the bamboo. More than two-thirds of the Japanese forest is secondary growth or young plantations of conifers, and in most of these, canopy height is lower than that of P. pubescens.The continuous area increment in bamboo from 1953 to 1985, positive current expansion rate in the front of unmanaged bamboo stands and the advantageous stand structure of bamboo suggest that the range expansion of P. pubescensin the secondary forest will continue in the future.  相似文献   
9.
With an area of 394,000 km2 (4.1% of China's total area) and specific diversified geographical environments, Yunnan houses over 18,000 species of higher plants (51.6% of China's total), 1,836 vertebrate species (54.8% of China's total) and multitu-dinous species of rare, endemic and epibiotic wildlife, ranking first in species richness value and endemicity rate of China's biodiver-sity, thus becoming a rare gene bank of wildlife species with the most concentrated distribution of important wildlife taxa and a key terrestrial biodiversity region of global significance. Despite its evident abundance and endemism, however, the biodiversity is faced with threats of ecological fragility and human disturbances in socioeconomic development resulting in attenuation of biodiversity, degradation of ecosystems and serious loss of species, thus, it needs to be carefully studied for its sustainability. Based on the analy-ses of the geographical diversity, the macro material bases of Yunnan's biodiversity were reviewed and six characteristics of the pro-vincial biodiversity were described in the ecosystems, forest types, species compositions, endemic species, genetic resources, etc. By appraising the present status of the provincial biodiversity conservation, the facts that the biodiversity coexisted with fragility were revealed so that eight key disadvantageous factors in the provincial ecological fragility causing serious biodiversity loss were sum-marized and described in this paper. In order to satisfy the two-fold needs of biodiversity sustainability and socioeconomic develop-ment, eight strategies for the sustainable development were intensively elaborated by borrowing certain theories in modern conserva-tion biology, recycling economics and some successful innovations, and by giving comprehensive consideration to the ecological fragility mechanism, nature reserve construction, environmental protection and the exploitability of resources for biodiversity sus-tainability and socioeconomic development. Accordingly, relevant targets, principles, tactics and measures for effective biodiversity conservation and sustainability were suggested to lay a solid theoretical foundation and reliable scientific basis for the biodiversity and socioeconomic sustainable development.  相似文献   
10.
Lord C, Brun C, Hautecœur M, Keith P. Insights on endemism: comparison of the duration of the marine larval phase estimated by otolith microstructural analysis of three amphidromous Sicyopterus species (Gobioidei: Sicydiinae) from Vanuatu and New Caledonia.
Ecology of Freshwater Fish 2010: 19: 26–38. © 2009 John Wiley & Sons A/S
Abstract –  The microstructure of otoliths of three amphidromous gobies (Sicydiinae) of the genus Sicyopterus has been analysed. One of these species, Sicyopterus lagocephalus has a widespread distribution whereas the other two are endemic ( Sicyopterus aiensis , from Vanuatu and Sicyopterus sarasini , from New Caledonia). The microstructural analysis of the otoliths showed that the duration of the marine larval phase is significantly shorter for both endemic species than for the cosmopolitan species (131 ± 3.4 days for S. lagocephalus , 79.2 ± 4.6 days for S. aiensis and 76.5 ± 3.9 days for S. sarasini ). These results led us to infer that it could be one of the factors explaining endemism. We have also improved our knowledge on the processes undergone during the marine phase by studying the growth of the otolith. This work allowed us to propose possible migration routes. These species' reproduction period has also been studied by back-calculating hatching dates. All these elements improve our understanding of the life-history traits and dispersion strategies of these species, which is crucial to implementing conservation measures in order to protect them and their environment, both threatened by anthropogenic actions.  相似文献   
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