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121.
正狼(Canis lupus)是食肉目(Carnivora)、犬科(Canidae)、犬属(Canis)食肉类哺乳动物(盛和林等,1999),是世界上分布最广和研究最多的大型食肉动物(Ripple et al.,2014)。目前,我国狼的分布已由过去的全国性分布缩小至东北、西北和内蒙等地区(Zhang,1999)。在斯洛伐克,研究人员通过无线电项圈获取分布在两个国家公园内两群狼的家域利用情况(Findo and Chovancova,2004),加  相似文献   
122.
【背景】珠穆朗玛峰地区具有寒冷低温、强辐射等极端环境条件,珠穆朗玛峰北坡石生微生物研究未见报道。【目的】针对珠穆朗玛峰北坡石生微生物开展研究,阐明珠穆朗玛峰北坡石生生境中可培养细菌多样性,开发珠穆朗玛峰北坡抗紫外辐射菌株资源。【方法】通过可培养法、16S rRNA基因序列分析方法以及紫外辐射筛选对珠穆朗玛峰北坡可培养石生细菌多样性以及抗紫外辐射能力进行研究。【结果】从珠穆朗玛峰北坡石生生境中共分离获得52株石生细菌,归类为放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes),其中放线菌门和变形菌门为优势菌门,鞘脂单胞菌属、节杆菌属、链霉菌属为优势菌属,有2株菌为潜在新种。从已分离鉴定菌株中筛选出了2株抗紫外辐射能力较高的菌株,分别是芽孢杆菌属菌株ZFBP4009和链霉菌属菌株ZFBP1009。【结论】珠穆朗玛峰北坡石生环境蕴含多样性丰富的石生细菌,所分离菌株抗紫外辐射能力突出,为揭示相关极端环境下微生物的分布特征及极端环境微生物资源开发提供了数据支持及菌株资源。  相似文献   
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ABSTRACT

A new fossil species of the genus Scutus (Scutus mirus n. sp.) is described from five Late Oligocene to Early Miocene (Waitakian to Altonian; 25.2–15.9?Ma) localities in the South Island, New Zealand. It is one of the oldest fossil species of Scutus known and probably inhabited very shallow, sub-tropical waters surrounding Zealandia during this time. The holotype of Scutus petrafixus Finlay, 1930 is re-examined; it is possibly from All Day Bay, Kakanui (Waitakian 25.2–21.7?Ma). The New Zealand species documented herein significantly expand our understanding of the fossil record of this shallow-marine molluscan lineage, and by proxy, also indicate the presence of very shallow coastal marine environments around the late Oligocene and early Miocene in southern Zealandia.  相似文献   
126.
Aim  We quantify the elevational patterns of species richness for all vascular plants and some functional and taxonomic groups on a regional scale on a tropical mountain and discuss some possible causes for the observed patterns.
Location  Mount Kinabalu, Sabah, Borneo.
Methods  A data base containing elevational information on more than 28,000 specimens was analysed for vascular plant distribution, taking into account sampling effort. The total species richness pattern was estimated per 300-m elevational interval by rarefaction analyses. The same methods were also applied to quantify species richness patterns of trees, epiphytes, and ferns.
Results  Total species richness has a humped relationship with elevation, and a maximum species richness in the interval between 900 and 1200 m. For ferns and epiphytes the maximum species richness is found at slightly higher elevations, whereas tree species did not have a statistically significant peak in richness above the lowest interval analysed.
Main conclusions  For the first time a rigorous estimate of an elevational pattern in species richness of the whole vascular plant flora of a tropical mountain has been quantified. The pattern observed depends on the group studied. We discuss the differences between the groups and compare the results with previous studies of elevational patterns of species richness from other tropical areas. We also discuss the methods used to quantify the richness pattern and conclude that rarefaction gives an appropriate estimate of the species richness pattern.  相似文献   
127.
We examined the basal area of two life forms (conifers vs. broadleaf trees) along elevational gradients on Yakushima Island, Japan and on two series of geological substrate on Mount Kinabalu, Borneo. On Yakushima, total stand basal area abruptly increased from 700 to 1,050 m in accordance with the high dominance of conifers, indicating the presence of additive basal area of conifers in conifer–broadleaf mixed forests at higher elevations (1,050–1,300 m). Along two substrate series on Kinabalu, some forests at higher elevations (1,860–3,080 m) showed relatively high dominance of conifers, but conifer basal area did not appear to be additive. Conifers were emergents above the canopy of broadleaf trees in mixed forests on Yakushima, but two life forms usually coexisted in the single-story canopy in mixed forests on Kinabalu. Litterfall rate as a surrogate of productivity decreased with decreasing temperature along elevation on both the sites, but the rate of decrease was slower on Yakushima, where mixed forests at higher elevations showed relatively high rates. Thus, we suggest that additive basal area of conifers was linked to their emergent status, and that it enhanced productivity by complementary use of light by two life forms that occupy different stories. On Yakushima, typhoons are a major disturbance, but do not severely limit the height growth of conifers, allowing the development of two-story mixed forests. On Kinabalu, a major disturbance is El Niño-driven drought, and hydraulic limitation to tree height may explain the non-additive and non-emergent nature of conifers.  相似文献   
128.
I studied the uses of the African cherry (Prunus africana) by four ethnic groups who live near the Kilum-Ijim Forest Preserve on Mount Oku, Cameroon. Prunus africana is valued for its timber, which is used for tool handles and for fuel, and it is an important wildlife food. However, its greatest value is for traditional medicines. Healers use the bark and leaves to treat more than 30 human ailments and several animal diseases and it is the most important plant used in their practices. This study is the first to document this importance, particularly for animal medicines. I also examined the growing worldwide herbal use to treat benign prostatic hyperplasia. Market demand has caused resource depletion and an erosion of traditional resource protection practices. Preservation of the species will depend on sustainable harvesting methods and on cultivation.
La Cerise Africaine (Prunus Africana): Du Manche De Houe Au Marche International D’herbes
Résumé  J’ai etudié I’emploi de la cerise africaine (Prunus africana) par quatre groupes ethniques residant prés de la préserve forestiére Kilum-Ijim surle Mont Oku, au Cameroun. Prunus africana est prisé pour son bois, qui est utilisé pour fabriquer des manches d’outils, et comme combustible. C’est également un aliment important pour la faune sauvage. Pourtant, sa plus grande valeur est dans la medecine traditionnelle. Les guerisseurs en utilisent l’écorce et les feuilles pour trailer plus de 30 maladies humaines et plusieurs maladies animates; c’est la plante la plus importante utilisée dans leurs cures. Cette étude est la premiére á documenter cette importance, particuliérement dans le domaine des médicaments pour les animaux. J’ai aussi examiné son usage mondial croissant comme traitement de I’hypertrophie bénigne de la prostate. La demande économique a causé une dépletion des ressources et une érosion des pratiques traditionnelles de protection des ressources. La préservation de cette espéce exigera des méthodes de moisson soutenables ainsi que la cultivation.
  相似文献   
129.
Zonation of forest vegetation and soils of Mount Cameroon,West Africa   总被引:1,自引:0,他引:1  
Mount Cameroon is an active volcano in a wet part of West Africa. The forest vegetation and associated soils on its southern slopes were studied in 1989, 1991 and 1995 in coupled 0.25 ha plots at altitudes of 180, 600, 1,100, 1,800 and 2,180 m. All lianas and trees >10 cm dbh were enumerated and their structural features quantified. The forests were of large stature throughout. The strangling Schefflera species made a substantial contribution to the very high basal areas at 1,800 m. The associated soils were dominated by andisols derived from volcanic ash that showed a distinct increase with altitude in soil organic matter and total N attributed to lower temperatures. Soil pH, exchangeable K+, Ca2+, Mg2+, effective cation-exchange capacity and percentage base saturation showed very marked increases explained by the influence of recent volcanic ashfalls. Available N and P showed less distinct trends with altitude. Although there is a large decrease in tree species richness with altitude, forest stand growth (as compared on a basal area basis) does not appear to be limited by soil fertility or temperature. The forest line (altitude treeline and extensive gaps below it) appear to be controlled by periodic volcanic activity, ashfalls and lava flows, which can destroy existing forest through soil burial and fire effects and inhibit regrowth on bare lava flows and deep deposits of volcanic ash.  相似文献   
130.
Abstract. We predicted that plants that can establish on volcanic soils with similar disturbance histories will have similar growth characteristics. We tested this prediction by a multivariate analysis of 27 traits of 84 species found six years after an eruption on Mount St. Helens, Washington State, USA, and Mount Usu, Hokkaido, Japan. These traits include vegetative, life-history, phenological and seed-biology characteristics. Cluster analysis revealed five species groups: annual herbs, perennial forbs, graminoids, shrubs and trees. Each group has distinct vegetative, life-history, and seed-biology traits. Except for shrubs, which were lacking on Mount Usu, both floras were well represented in each group. On intensely disturbed sites on both volcanoes, perennial forbs, whose development is dependent primarily on well-developed below-ground organs and wind-dispersal, expanded their cover more rapidly than did graminoids. These graminoids generally produce gravity-dispersed seeds and have close-set rhizomes and/or shoots. These results suggest that species that can establish during the early stages of succession on each volcano have similar vegetative, life-history, and seed-biology traits.  相似文献   
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