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1.
珍稀濒危和特有物种是地区生物物种的重要组成,研究珍稀濒危和特有物种的多样性对生物保护和良好生态环境的维护有重要意义。本文在对桂林喀斯特世界自然遗产提名地生物物种调查的基础上,对提名地内的珍稀濒危和特有生物物种及其受威胁级别情况进行了统计,并从种群、群落和生境3个层面对珍稀濒危和特有物种的保护提出了建议。结果表明,在167.5 hm2范围内共有高等植物754种,脊椎动物525种;列入 IUCN红色名录443种、濒危野生动植物国际贸易公约67种、中国物种红色名录145种、中国国家重点保护野生动植物55种,并包括部分古老孑遗植物,珍稀濒危生物多样性较高;此外提名地还拥有87种特有种,是动植物特有种的重要资源地。在珍稀濒危和特有物种多样性的保护上,应根据提名地的珍稀濒危物受威胁级别,有计划地开展种群调查和生境分析,确定不同级别珍稀濒危物种的最小生存种群和最小动态区,并采取就地保护或迁地保护的措施,以促进小种群的发展;加强顶级群落的保护和监测研究,实施封山育林和群落恢复工程,促进群落的正向演替;划定珍稀濒危和特有种群和群落保护范围,建立自然保护区,维护其生存繁衍所必需生境量;此外着重加强对野生兰科植物的研究及生存空间保护,加强洞穴、峰林、峭壁等独特生境的保护。  相似文献   

2.
赵阳  张媛媛  赵亚辉 《中国岩溶》2021,40(6):1032-1037
世界自然保护联盟(IUCN)物种红色名录是全球范围使用的有效评估物种灭绝风险状况的正式标准,但对于洞穴鱼类评估在实际操作层面仍面临很大挑战.文章回顾了中国洞穴鱼类的现状以及红色名录评估体系对洞穴鱼类评估存在的问题.基于IUCN红色名录濒危评估体系,根据物种分布范围、受威胁因素和物种生活特性等,构建了中国洞穴鱼类濒危等级...  相似文献   

3.
Major mountain environments of the world are delineated and all their protected areas (MTNPA) are listed by IUCN categories. MTNPA are those places subjected to nature conservation such as national parks and nature reserves. A total of 442 IUCN Category I–IV areas with a minimal size of 10,000 ha and a minimal relief of 500 m are listed. These MTNPA constitute 42 percent of the world's area devoted to nature conservation. Summaries of the mountain protected areas in each biogeographical realm are given, sites of international importance are identified and observations are made on lacunae. The review concludes with six recommendations for more and better managed mountain parks and reserves.  相似文献   

4.
《Geoforum》1987,18(3):291-319
The role of national parks and protected areas in National Conservation Strategies (NCS), a key element in the 1980 World Conservation Strategy, is analyzed for the nine countries of Australia, Belize, Canada, Czechoslovakia, India, Senegal, the United Kingdom, Vietnam and Zambia. These NCS responses are described, evaluated and synthesized primarily for 12 national park and protected area functions identified through a review of the recent literature. National parks and protected areas are found to be involved in the nine NCS in uneven and less than optimal ways. Furthermore, little relationship can be found among the various proposed roles of national parks and protected areas and the socio-economic and other characteristics of the nine countries under study. As a basis for improving both NCS and the role of national parks and protected areas, a better NCS information system is recommended for the International Union for Conservation of Nature and Natural Resources (IUCN) headquarters, Gland, Switzerland. IUCN Commissions also are urged to be more active in NCS work. More research also is recommended especially on the role of national parks and protected areas in regard to regional planning and development, indigenous and local people, and comprehensive land use management. Finally, special efforts should be made by IUCN, and other related international, national, provincial and regional agencies, to ensure their personnel are knowledgeable about NCS and the range of functions that national parks and protected areas can contribute to them, and so to sustainable development globally.  相似文献   

5.
青海高原湿地特征及其保护   总被引:39,自引:11,他引:28  
青海省地处青藏高原东北部,是我国长江、黄河和澜沧江的发源地,素有"江河源"之称.青海高原湿地类型包括自然湿地和人工湿地两大类型,湿地总面积约55662.7km2,占全省土地总面积的7.7%.高原湿地分布特点主要表现为3种形式:1)以湖泊或浅塘为中心的环带状分布;2)以河流为中心的条带状分布;3)河源区的斑块状镶嵌分布.高原湿地生物种类较为丰富,有湿地种子植物约428种;湿地动物约151种,其中鸟类约73种、鱼类约55种、哺乳类约14种以及两栖类9种.湿地植被有水生植被、沼泽植被和沼泽草甸3大基本类型.近几十年来,青海高原湿地出现湖泊水位下降、湖泊面积萎缩、河流出现断流以及沼泽湿地退化等方面的明显变化.鉴于高原湿地的生态功能和作用,应加强青海高原湿地的保护.  相似文献   

6.
We studied variation in bird assemblages with plant associations for three different coastal marshes from Southeastern South America (SESA) and assessed how marsh bird assemblages related to nearby upland bird assemblages. We surveyed bird species and plant structure along the tidal gradient of each locality from the low tide level to the upper habitats bordering coastal marshes. Twenty species frequently used coastal marshes, including relatively few migratory species. We found that birds occurring in SESA coastal marshes do not have distributions constrained to coastal marshes. Nonetheless, four bird assemblages were recognized in association with vegetation types and/or sites. Among the recorded coastal marsh species, the bay-capped wren-spinetail (Spartonoica maluroides) is both the most frequent and the most habitat constrained. Bird richness increases steadily along the tidal gradient associated with the increase in vegetation structure, suggesting that bird richness is directly explained by vegetation and indirectly by the physical conditions influencing vegetation structure. Results highlight the importance of SESA middle marshes as habitat for conservation of some threatened SESA grassland birds.  相似文献   

7.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

8.
山西静乐县“静乐期”地层及大哺乳动物化石   总被引:12,自引:2,他引:10       下载免费PDF全文
陈晓峰 《第四纪研究》1994,14(4):339-353,385
最近在山西静乐县贺丰村的静乐组地层中的发掘,丰富了贺丰动物群的种属。新发现的大哺乳动物化石包括两种食肉类:Nyctereutessinensis和Metailuruscf.major。新的发掘也为以往发现过的种属增加了更多有价值的材料。根据动物群分析和古地磁资料,笔者认为,贺丰动物群的时代为晚上新世早期,年代为3.0MaB.P.前后。静乐组的时代应与榆社麻则沟组时代相当。  相似文献   

9.
This paper engages with contemporary debates in labour geography through its focus on: migrant workers as active agents of change; precarious employment, its complexities and consequences; and the importance of material spaces in migrant labour struggles. Since the early 2000s the South Korean government has been strengthening the institutionalised regulation of low-wage migrant workers. A key tool in this process is the Employment Permit System (EPS), in force since 2004. Under this policy migrant workers are temporary sojourners and effectively socio-politically, culturally and spatially excluded from Korean society. EPS restricts migrants’ freedom to choose or change workplaces, which renders them vulnerable to economic and social precarity. Employers use these restrictions to segregate migrant workers from co-nationals, and low-waged migrant workers often find themselves in exploitative working conditions in isolated places. This paper is based on deep ethnographic fieldwork in “Nepal Town” in Seoul and remote Nepalese workers’ accommodation. We examine how such precarious working conditions and isolation impact on workers’ active involvement in the formation and transformation of Nepal Town in Seoul. We examine the ways in which Nepal Town is a site of spatial agency and praxis for Nepalese workers and explore the potentialities of ‘reactive ethnicity’. The empirical insights provided, suggest that the regulatory migration regime for low-wage migrant workers is strongly linked with new formations of material landscapes of connection, mobility, freedom and safe space. Such space production enables migrant workers to perform agency and employ tactics of resistance in order to create spaces of possibility.  相似文献   

10.
The Wapiti Formation in west-central Alberta preserves one of the most diverse Late Cretaceous terrestrial track records yet identified in Canada. At least seven morphotypes are recognized and attributed to mammals, small reptiles or amphibians, tyrannosaurids, medium-sized theropods, hadrosaurids, and ankylosaurs. Most tracks occur isolated on slump blocks associated with latest Campanian (Wapiti Formation unit 4) exposures found along Pipestone Creek and Red Willow River. With the possible exception of hadrosaurids, tracks provide some of the most compelling evidence for the occurrence of such taxa within the Wapiti Formation ecosystem. The apparent absence of ceratopsian tracks is surprising considering their bones are abundantly preserved in nearby monodominant bonebeds. The overall faunal signal represented by the Wapiti Formation trackmakers is typical of and consistent with other coeval assemblages in similar environments. The Wapiti Formation tracks, combined with the known fossil bone record, provide another data point in a growing palaeobiogeographical picture of the dinosaur faunas of high-latitude northwestern North America during the Late Cretaceous.  相似文献   

11.
山东中新世山旺组生物群的古生态   总被引:3,自引:1,他引:2       下载免费PDF全文
山东临朐产出的中新世山旺组化石群,保存精美、属种分异度高。50多年来,经发掘和研究,目前已从约30余米的硅藻页岩沉积中报导了真菌、硅藻、介形虫、孢粉、昆虫、鱼类、两栖动物、爬行类、鸟类、哺乳动物及遗迹化石等十几个门类的化石,共计400余属700多种。本文总结了化石与周围无机界的关系、化石的埋藏特征、形成原因以及相关古生态学问题――古气候、古温度、古纬度、古地形、山旺湖的水文性质、湖水的季节性变化与硅藻页岩的纹层、动植物群的营养结构以及山旺盆地的沉积历史。  相似文献   

12.
《Quaternary Science Reviews》2007,26(22-24):2970-2995
Vertebrate and invertebrate faunal biostratigraphy is a well-tested method for establishing relative chronologies for fluviatile sequences that has proved useful in many parts of the world. The robust bones and teeth of large mammals are commonly found in fluviatile deposits, whereas small vertebrates can be readily recovered through systematic sieving of calcareous sediments, as can molluscs, the other major faunal group that has been used for biostratigraphical analysis of fluvial sequences. Because of their rapid and quantifiable rates of evolution, extinction, body mass change and dispersal during the Late Cenozoic, mammals are especially useful for ordering the fragmentary terrestrial sequence of interglacials and glacials, and proposing correlation with the global marine climatostratigraphic record. Other groups (e.g. reptiles and amphibians, ostracods) are as yet only in the initial stages of development as a dating tool, whereas some (e.g. fish, birds) still require substantial development in order to fully explore their utility. As part of IGCP 449, vertebrate and molluscan assemblages have made important contributions to datasets from a number of areas, notably northern France, central Germany, the Czech Republic and the Ukraine. Further south, mammalian assemblages have proved useful in separating discrete periods of climatic change in Iberia and Syria. At greater distances from the core area of fluvial biostratigraphical archives, significant contributions have come from South America (Uruguay River), South Africa (Vaal) and Australia (Riverine Plain and Lake Eyre drainage basin).  相似文献   

13.
Spheres of discharge of springs   总被引:3,自引:0,他引:3  
Although springs have been recognized as important, rare, and globally threatened ecosystems, there is as yet no consistent and comprehensive classification system or common lexicon for springs. In this paper, 12 spheres of discharge of springs are defined, sketched, displayed with photographs, and described relative to their hydrogeology of occurrence, and the microhabitats and ecosystems they support. A few of the spheres of discharge have been previously recognized and used by hydrogeologists for over 80 years, but others have only recently been defined geomorphologically. A comparison of these spheres of discharge to classification systems for wetlands, groundwater dependent ecosystems, karst hydrogeology, running waters, and other systems is provided. With a common lexicon for springs, hydrogeologists can provide more consistent guidance for springs ecosystem conservation, management, and restoration. As additional comprehensive inventories of the physical, biological, and cultural characteristics are conducted and analyzed, it will eventually be possible to associate spheres of discharge with discrete vegetation and aquatic invertebrate assemblages, and better understand the habitat requirements of rare or unique springs species. Given the elevated productivity and biodiversity of springs, and their highly threatened status, identification of geomorphic similarities among spring types is essential for conservation of these important ecosystems.  相似文献   

14.
Qualitative and quantitative characterization of mangrove vegetation structure and dynamics is required for assessment of coastal habitat vulnerability. Changes in mangrove forests around Douala, Cameroon, have been documented using aerial photography between 1974 and 2009. The distribution pattern of tree species was also assessed in 2009 following the point-centered quarter method (PCQM+) protocol. Pristine mangroves observed in 1974 had been disturbed markedly in 2003 and 2009. Some of the pre-existing mangroves were entirely replaced by settlements, road, and crops (maize, bean, banana, oil palm, green vegetables, and sugar cane plantations). From 1974 to 2003, 39.86 % of mangrove forests have disappeared; the net loss of 22.10 % occurred between 2003 and 2009 alone. Mangrove forest area had decreased 53.16 % around Douala over a 35-year period from 1974 to 2009 concurrent with a substantial increase of settlements (60 %), roads (233.33 %), agriculture areas (16 %), non-mangrove areas (193.33 %), and open water (152.94 %). Field survey showed that almost one third of the quadrants in the remaining mangrove forest were empty. The disrupted mangrove forest has an overall mean height, absolute density, and basal area of 19.80 m, 158 trees ha?1, and 110.44 m2 ha?1, respectively. In comparison with scientific literature on mangrove degradation, this puts the mangroves around Douala at the top of the “peri-urban mangrove degradation” list. In addition, beyond listing of mangrove plants on the Red List of Threatened Species which will seldom lead to widely distributed species being listed, we call for the creation of a Red List of Locally Threatened Ecosystems, which in contrast is likely to list mangroves as an ecosystem under critical risk of (local) extinction in many countries around the globe, in particular, peri-urban sites.  相似文献   

15.
利用尼泊尔已发布的冰川编目数据、遥感数据及DEM数字高程模型,利用GIS和Excel对尼泊尔境内冰川的结构特征及1980-2010年的冰川变化特征进行了分析,并运用冰川系统功能模型模拟了同期尼泊尔冰川的变化趋势。结果表明:(1)尼泊尔境内冰川平均规模较小,且冰川分布的海拔差异大。(2)尼泊尔冰川平衡线高度分布受地形影响明显,呈现出反纬向性变化特征,存在若干以高峰为中心的高值区域。(3)1980-2010年尼泊尔冰川整体呈现退缩状态,冰川数量增加了378条,冰川面积和体积均减少,分别减少了24%和29%;小规模冰川或冰川系统退缩更快,1980-1990年冰川变化速率最快。(4)采用历史时期的气温变化率,冰川系统功能模型可以较好地模拟冰川历史时期的变化特征。  相似文献   

16.
基于最新的分类系统,对中国典型洞穴鱼类名录、分布、受胁状况及部分特征进行了整理。结果表明:中国境内已发现典型洞穴鱼类2目4科13属90种,其中鲤科的金线鲃属(38种)和条鳅科的高原鳅属(25种)为物种数较多的属。典型洞穴鱼类的体型较小,数量稀少,分布狭窄,研究资料很少,63%的种类的受胁等级数据缺乏或未被评估。对鳞片、眼睛和体表色素的统计分析显示,这3种形态特征的退化情况并不同步,推测它们在洞穴鱼类的演化过程中可能是相互独立的。   相似文献   

17.
David Turnock 《GeoJournal》2001,55(2-4):655-681
Cross-border cooperation in environmental matters has become much more evident since 1989 because open frontiers facilitate contact while common tasks emerge as protected areas in frontier zones lose their isolation. Pollution hazards have been discussed more openly since 1989 while further stimuli arise from the harmonisation process in the run-up to EU enlargement and the finance available from Brussels and other international donors to solve pollution problems and create international ecological networks. The paper examines the progress made in the Danube Valley and the Carpathians which together constitute the core of East Central Europe. Particular attention is paid to the role of environmental non-governmental organisations (ENGOs) – and especially the World Wide Fund for Nature (WWF) – in the progress of conservation. Along with the World Conservation Union (IUCN), WWF has demonstrated the value of floodplain wetlands and ensured that wetland restoration is an important part of the Strategic Action Plan for the Danube. And by involving local ENGOs in specific projects the role of the non-governmental sector in environment matters is enhanced. Also, with momentum growing for a pan-European ecological network ('Natura 2000'), WWF has attracted the support of international donors for a ecoregion-based conservation (ERBC) in the Carpathians where priority areas have now been identified. Ecological and diplomatic capacities are thus deployed to maximise the scope for biodiversity conservation commensurate with sustainable socio-economic development. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
Analysis of late Pleistocene fossils recovered from near the Huntington Beach, California (USA), pier (site LACM 7679) has revealed a diverse fauna dating to approximately 40 14C ka BP. Extinct megafauna (three genera) are present; however, a microfauna including three genera of fish, five genera of amphibians, twelve genera of reptiles, two genera of birds, and ten genera of small mammals dominates the assemblage in terms of diversity. Additional identification of seven genera of non-marine mollusks and various macro- and microscopic plant remains including grasses, three families of herbs, and seven genera of trees provides a wealth of information concerning the past ecology of what is currently a coastal dune field complex. During the Rancholabrean Period, the LACM 7679 locality was approximately 10 km inland from the Pleistocene coastline and contained lush riparian zones interspersed with coastal sage scrub, a few trees, and grasslands teeming with a variety of small and large animals.  相似文献   

19.
Region warming and the resulting ongoing deglaciation have led to the formation of new glacial lakes and expansion of existing glacial lakes. For giving an overview of the distribution and expansion of glacial lakes in the Koshi River Basin (KRB) between the Central China and Nepal Himalayas in the recent 10 years, this paper aimed to analyze and assess recent spatial variability of glacial lake changes in the KRB, Central Himalayas using two inventory data of glacial lake in 2001 and 2010 in Nepal and Landsat TM/ETM+ data for the 1990s, 2000 and 2009 on the Chinese section of the KRB. The datasets show that there are 1,203 glacial lakes with a total area of 118.54 km2 in the KRB in 2009, in which 599 lakes are mapped in the Nepalese section of the KRB with a total of 25.92 km2, and 604 lakes in the Chinese section of the KRB with a total area of 92.62 km2. From 2000 to 2009, the total number of glacial lakes decreased from 1,668 to 1,203 with a reduction of 45.86 % in the KRB, whereas the total lake areas expanded by 10.60 % (i.e. 0.72 km2/a), from 111.35 to 118.54 km2 between 2000, 2001 and 2009, 2010. Especially, 17 lakes are identified as potentially dangerous glacial lakes (PDGLs) by International Centre for Integrated Mountain Development (ICIMOD) on the Nepalese section of the KRB in 2009. In the same period, 23 PDGLs are also identified on the Chinese section of the KRB and the total area increased by 77.46 % (i.e. 0.37 km2/a) from 1990 to 2010 and the expansion rate is significantly higher than 39 % (0.19 km2/a) of non-PDGLs. Therefore, there is a need for promoting the awareness of the hazard potential of glacier lakes to support proper planning of mitigation and adaptation strategies in this context.  相似文献   

20.
近年来,在中国辽宁西部、内蒙古东南部、河北北部中侏罗世髫髻山组和九龙山组中发现了丰富的脊椎动物、无脊椎动物和植物化石,这一化石群被称为燕辽生物群。燕辽生物群已正式命名的脊椎动物26属28种,包括鱼类1属1种、两栖类4属4种、有鳞类1属1种、翼龙类10属12种、兽脚类恐龙5属5种、哺乳类5属5种。燕辽生物群的脊椎动物化石对研究长羽毛兽脚类恐龙的演化、翼龙类的分类演化、滑体两栖类的分异等具有重要意义。虽然辽宁西部及邻区燕辽生物群脊椎动物的多样性不及同一地区早白垩世的热河生物群,但它为认识这一地区晚中生代生物群的演替提供了极为重要的依据。  相似文献   

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