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1.
云南省小黑山自然保护区兰科植物多样性及保护评价   总被引:7,自引:0,他引:7  
云南省小黑山自然保护区孕育了丰富的兰科植物。据调查,保护区有兰科植物43属、134种,约占云南省135属、780种的31.9%和17.2%,是保护区种子植物种类最多的科。兰科植物在保护区的各个生态类型中均有出现。保护区134种兰科植物以附生兰占优势,占67.16%(90种);其次,地生兰占31.34%(42种),腐生兰为1.50%(2种)。保护区兰科植物起源于新、旧世界的热带和温带,热带属占70.0%(28),温带属占27.5%(11)。鉴于兰科植物重要的保护价值,应加强保护区兰科植物的保护。首先应加强保护区的建设和管理,还应加强社区经济发展,加强科学研究,实施社区共管以及加大保护宣传力度。  相似文献   

2.
目的:CArG元件因其为血清反应因子识别的结合位点近年来备受关注。然而迄今为止尚未见到有关CArG元件的序列特征及进化模式的研究。方法:本研究应用生物信息学方法结合遗传学方法对小鼠及人基因组中CArG元件的位置分布序列类型、多样性及保守性进行深入研究。结果:多样性研究结果显示,CArG元件的序列在小鼠及人类基因组存在大量的不同类型。但是,小鼠和人基因组中CArG元件的主要类型又存在明显差异。同源性分析结果表明人类和小鼠中的CArG元件存在两种进化历程,一部分CArG元件拥有共同的祖先,一部分是在物种分化以后突变产生的。结论:上述研究结果将为更为深入阐述SRF的调控模式奠定理论基础,同时为更清楚的阐释CArG元件序列变化对下游基因的表达影响提供理论支持。  相似文献   

3.
生态系统途径——生态系统管理的一种新理念   总被引:18,自引:2,他引:18  
汪思龙  赵士洞 《应用生态学报》2004,15(12):2364-2368
介绍了生态系统途径的概念和内涵.生态系统途径最早由西方生态学家提出。随后得到一系列国际学术组织和国家的认同和支持,其中《生物多样性公约》、世界自然保护联盟和世界野生动物基金发挥了重要作用,.生态系统途径的实质是对土地、水和生物资源进行综合管理,旨在生态系统保护、生物资源可持续利用和共享生物资源三者之间达到平衡.作为生态系统管理的一种方法论,它以生物为核心。将人类及文化的多样性视为生态系统的一个组成部分,2000年《生物多样性公约》缔约国会议上制定的生态系统管理的12条基本原则和5项行动指南,丰富了生态系统途径的内涵,明确了实施的办法,我国在生态系统管理方面有着丰富的学术储备和经验总结。但也存在一定问题。

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4.
Disturbance has long been recognized as an important determinant of community characteristics in aquatic systems. The aims of our study were to evaluate the impact of different disturbances on the macrophyte diversity and on river quality. To this end, we investigated the floristic composition for different stretches impacted by disturbances and we tested both diversity indices and the trophic index (IBMR) “Biological Index Macrophytes in Rivers” in the Moselle river (NE of France). The river was divided into four sections of different lengths based on uniformity of morphological characteristics, substrate conditions and flowing velocity: the upper, the wild, the resectioned and the downstream Moselle. Floristic composition and water chemical parameters were analysed from 1999 to 2001. The man‐made increase of nutrient concentration favoured the floristic richness in the last sites of the upper Moselle, whereas river dynamics and floods did not allow the development of vegetation in the wild Moselle. Disturbances caused by industrial sewage and eutrophication allowed the spreading of pollu‐tolerant and riparian alien species. The aquatic macrophyte approach is a useful means to detect impact of disturbances on diversity and on river quality. However, it was not effective in assessing disturbances such as flood overflow or chemical pollution. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

5.
Economic instruments that promise “win-win” solutions for both biodiversity conservation and human livelihoods have become increasingly popular over recent years. There however remains a gap in terms of practical and policy-relevant guidance about appropriate approaches that take into account the local needs and the specific cultural, legal, and ecological context in which such instruments are being developed and applied. This paper presents a step-by-step framework that helps conservation and development planners and practitioners to identify economic instruments that can promote pro-conservation behaviour in a specific setting. The concept of ‘ecosystem service opportunities’ builds on, and brings together, general economic principles and an ecosystem services perspective. The framework was designed to also address a number of concerns regarding economic approaches in order to help practitioners recognise the potentials and limits of economic approaches to nature conservation. The framework is illustrated by its application within the realm of a biodiversity conservation project in Thailand.  相似文献   

6.
For any conservation strategy to be effective, it must be preceded by knowledge of how diversity is configured within the area of interest. Here, data from 40 savanna-grassland sites were used to examine how plant biodiversity and species composition varied across spatial scales at the Kalakad-Mundanthurai Tiger Reserve (KMTR), south India. Grasslands surveyed contained 278 plant species, and were characterized by high spatial variability in species association patterns. Fourteen distinct community assemblages were identified, organized primarily along an elevation gradient in the reserve. Overall, grasslands at KMTR were characterized by the dominance of a few, widespread species. The bulk of species richness, however, resulted from subordinate species with fairly restricted distributions. At low elevations, grasslands had high species richness and species composition differed greatly between sites. Mid-elevation grasslands contained about half the number of species present at low elevations, but sites were more similar in species composition. Richness of high-elevation grasslands was a third of that found at low elevations, but different sites harbored unique sets of species. Herbivore use of grasslands varied between communities and showed patterns that coincided with elevation. Herbivore use of low-elevation communities was high albeit variable, of mid-elevation sites was consistently low, and increased at higher elevations. Tall grass communities were the least utilized by herbivores at all elevations. Most species surveyed were rare and restricted in their distribution suggesting that conservation efforts must, perforce, encompass the entire reserve. However, differences in the structuring of diversity across elevations, and in herbivore use of grasslands, suggest that conservation efforts can be partitioned differentially across locations, specifically targeting low and high elevation grasslands in the reserve.  相似文献   

7.
生态系统健康与人类可持续发展   总被引:95,自引:16,他引:95  
生态系统健康学是近年来出现的一门探讨资源环境管理对策的综合性新学科.本文介绍了生态系统健康概念的由来、内涵以及生态系统健康学的主要研究内容;阐述了生态系统健康与人类可持续发展的关系;文中还对国际上一些主要的生态系统健康实践作了介绍,并建议我国应尽快开展生态系统健康研究.作者认为生态系统健康学必然为人类社会的健康、持续发展提供新的希望.  相似文献   

8.
北美保护性耕作及对中国的意义   总被引:67,自引:8,他引:67  
由土壤侵蚀、荒漠化及盐碱化导致的耕地地力退化,严重威胁着中国的农业生产和生态环境.为了阻止耕地地力的持续下降和生态环境进一步恶化,土壤管理方式必须由传统的耕作方式转向保护性耕作.纵观20世纪有关治理耕地水土流失的技术方法,没有哪一项技术可与由美国提出并加以完善的保护性耕作相比.美洲的农业实践证明,保护性耕作可以控制土壤侵蚀,减少劳动量,节省时间和能源,改善土壤耕性,增加土壤有机质,改善水和大气质量,增加土壤生物多样性.通过回顾保护性耕作的发展历史和应用现状。强调了该耕作技术在保持水土和改善土壤性状上的价值和采用保护性措施时应该注意的关键问题。如保护性耕作农机具、化学除草和转变观念等,同时总结了农民在采用保护性耕作时应该采取的具体步骤.总之,面对中国耕地土壤水土流失严重和地力持续下降以及生态环境恶化的严酷现实,保护性耕作应该在中国加以推广采用.  相似文献   

9.
Freshwater environments are currently experiencing an alarming decline in biodiversity. As a result, scientists and managers must look for alternative management techniques to protect these aquatic systems. One such option that has potential to protect freshwater environments from numerous threats is the use of freshwater protected areas (FPAs). FPAs are portions of the freshwater environment partitioned to minimize disturbances and allow natural processes to govern populations and ecosystems. While similar conservation practices are well established in the terrestrial and marine environments, the use of FPAs for conservation of freshwater environments has been relatively slow. Despite this, numerous examples exist in which FPAs have been incorporated into successful management approaches for freshwater environments. In this paper, we outline some of the past success stories where FPAs have been used to protect freshwater environments, discuss some of the reasons that this technique has not proliferated to the same degree as marine protected areas, and present some of the challenges that managers and scientists must overcome if they wish to implement FPAs. We recommend that the term Freshwater Protected Area be adopted to such conservation efforts, thereby standardizing terminology and facilitating literature searches and dissemination of research findings. Furthermore, we encourage freshwater scientists, conservationists and managers to develop and implement FPAs in innovative and creative situations thereby permitting the growth of the research base for this valuable conservation technique.  相似文献   

10.
土壤细菌DNA提取及多样性分析的T-RFLP方法   总被引:2,自引:0,他引:2  
获得高质量的土壤总DNA是土壤细菌生态学的关键步骤之一.实验通过综合应用两个试剂盒(Soilmaster kit和DNA IQTM系统)的优点进行土壤样品总DNA的提取,结果证明该方法是一种快速、有效、灵敏、稳定的土壤DNA提取方法.另外尝试将16S rDNA序列和T-RFLP(Terminal restriction fragment 1ength polymorphism)技术引入土壤细菌DNA群落多样性的研究中,证明T-RFLP是一种有力的土壤细菌多样性分析工具.  相似文献   

11.
The need to combine data from CO2 field experiments with climate data remains urgent, particularly because each CO2 experiment cannot run for decades to centuries. Furthermore, predictions for a given biome need to take into account differences in productivity and leaf area index (LAI) independent of CO2-derived changes. In this study, we use long-term weather records and field data from the Jasper Ridge CO2 experiment in Palo Alto, California, to model the effects of CO2 and climate variability on ecosystem water fluxes. The sandstone and serpentine grasslands at Jasper Ridge provide a range of primary productivity and LAI, with the sandstone as the more productive system. Modeled soil water availability agreed well with published observations of time-domain reflectometry in the CO2 experiment. Simulated water fluxes based on 10-year weather data (January 1985–December 1994) showed that the sandstone grassland had a much greater proportion of water movement through plants than did the serpentine; transpiration accounted for approximately 30% of annual fluxes in the sandstone and only 10% in the serpentine. Although simulated physiological and biomass changes were similar in both grasslands, the consequences of elevated CO2 were greater for the sandstone water budget. Elevated CO2 increased soil drainage by 20% in the sandstone, despite an approximately one-fifth increase in plant biomass; in the serpentine, drainage increased by <10% and soil evaporation was unchanged for the same simulated biomass change. Phenological changes, simulated by a 15-day lengthening of the growing season, had minimal impacts on the water budget. Annual variation in the timing and amount of rainfall was important for water fluxes in both grasslands. Elevated CO2 increased sandstone drainage >50 mm in seven of ten years, but the relative increase in drainage varied from 10% to 300% depending on the year. Early-season transpiration in the sandstone decreased between 26% and 41%, with elevated CO2 resulting in a simulated water savings of 54–76 mm. Even in years when precipitation was similar (e.g., 505 and 479 mm in years 3 and 4), the effect of CO2 varied dramatically. The response of grassland water budgets to CO2 depends on the productivity and structure of the grassland, the amount and timing of rainfall, and CO2-induced changes in physiology. In systems with low LAI, large physiological changes may not necessarily alter total ecosystem water budgets dramatically. Received: 11 March 1997 / Accepted: 23 September 1997  相似文献   

12.
The present study evaluated the usefulness of collection of location specific data for assessing patterns of species diversity and endemism based on a dataset for the 10 temperate flowering plant families from the Indian Himalaya Region. Analysis was based on 818 grid cells (15 × 15′) representing throughout the Indian Himalayan Region (IHR). Based on the existing information on diverse aspects of the selected plant families four indices, i.e., species richness, weighted endemism, 1–4 cell endemism and corrected weighted endemism were developed and mapped for selected plant families. Analysis revealed that endemism is significantly (P < 0.001) correlated with species richness (1–4 cell endemic index: r = 0.85; weighted endemism; r = 0.58). On the basis of four different indices, potential areas have been identified for conservation. Data of each indices have been overlaid to each other for identification and prioritization of endemic rich areas in the Indian Himalayan Region.  相似文献   

13.
In this article we summarize estimates of genetic variation based on allozymes for 30 non-social spider species. Overall, these species show moderate levels of genetic variability (mean Ho = 6.8%) compared to other invertebrate species surveyed for allozymes, although a number of spiders possess only minimal variation. Fossorial spiders, especially those which are coastal dune dwellers, typically display less variation than other non-social arachnids. In general, differences in heterozygosity estimates between groups of non-social spiders in this article are not confounded by the varying mix of proteins that have been assayed by individual investigators. There is a significant positive relationship between genetic variability and gene flow (Nm), indicating that non-social spider populations which exhibit reduced variability are likely to be genetically isolated. Population bottlenecks, directional selection and environmental homogeneity have all been cited to account for reduced variability in particular non-social spiders. In addition, an analysis using the genus Lutica suggests that low genetic variation may be accompanied by decreased population fitness. Since the potential for evolutionary change is dependent on the existence of genetic variability, our findings indicate that a number of non-social spiders may be at risk in terms of long-term population viability. This conclusion should be verified/extended via a combination of more genetic surveys; genetic and ecological monitoring of populations and their fitnesses in the wild; and experimental studies of the mechanisms underlying fitness differences.  相似文献   

14.
金钱槭属植物的遗传多样性与保护策略   总被引:1,自引:0,他引:1  
金钱槭属包括2个种:金钱槭(Dipteronia sinensis Oliv.)和云南金钱槭(Dipteronia dyeriana Henry),均为珍稀濒危植物,主要分布于中国的中部和南部。该研究应用18种随机扩增多态性DNA(RAPD)引物、8对扩增片段长度多态性(AFLP)引物和10种多态性叶绿体微卫星基因(cpSSR)引物,获得金钱槭和云南金钱槭的遗传多样性与种群结构的相关信息。结果表明,在物种水平上,由RAPD(金钱槭:H=0.386 4,Hsh=0.556 3;云南金钱槭:H=0.304 7,Hsh=0.445 0)和AFLP(金钱槭:H=0.331 9,Hsh=0.488 0;云南金钱槭:H=0.304 7,Hsh=0.4450)2个核标记的遗传多样性具有可比性,而cpSSR标记(金钱槭He=0.603 2,云南金钱槭He=0.671 1)的遗传多样性高于AFLP和RAPD标记的遗传多样性,遗传分化系数(GST)也显示出相似的结果,由此揭示2个种均拥有相对较高的遗传多样性和遗传分化。研究认为,人类活动破坏植物栖息地是造成2种物种处于濒危状态的主要原因;从长远来看,保护2种金钱槭属植物的主要策略是保护植物栖息地,同时应加强扩大种群规模以维持现有遗传变异水平。  相似文献   

15.
Large areas of the Rio Negro basin in Amazonia are covered by continuous tracts of tropical forest, but have few primate species. This is anomalous considering the general relationship between area and number of species. One possibility is that much of the forest is unsuitable habitat for most primates and the area of suitable habitat is much less than the forested area. This has important consequences for the design of reserves and predictions of the consequences of climate change, which tend to be based on broad categories based on satellite images, and not on information of species distributions within those broad categories. The study was conducted through diurnal and nocturnal line‐transect surveys in the Biodiversity Research Program 25‐km2 permanent grid in Viruá National Park, which has vegetation associations typical of much of northern Amazonia. The highest primate diversity and abundances occurred in tall terra firme forests (58%), whereas inundated forests and scrublands, which cover 42 percent of the survey grid and 90.8 percent of the Viruá National Park, have virtually no primates. This suggests that parks and reserves in northwestern Amazonia will have to be very large to maintain viable populations of most primates and their ecological interactions, and that very broad habitat categories are not sufficient to make predictions about actual and future suitability of areas for primate conservation.  相似文献   

16.
珊瑚礁生态系统是《生物多样性公约》(下称《公约》)的重点保护对象。自1998年珊瑚礁出现大规模白化现象以来, 珊瑚礁养护议题一直受到《公约》缔约方大会的关注。本文通过梳理我国珊瑚礁养护管理的法律法规和相关履约措施, 结合海南、广西、广东三省的珊瑚礁资源变化状况, 评价我国在履约方面的表现并识别存在的主要差距。研究发现, 总体上我国积极采取了多种措施进行珊瑚礁的养护和管理, 活珊瑚覆盖度和种类数量有一定程度的恢复, 但仍存在相关立法分散、综合性治理方案缺乏、气候变化适应不足、跨部门协调机制不完善、海洋保护区管理有效性不足、资金缺乏且当地社区参与度低、珊瑚礁监测标准和规范简单且不统一、监测数据不足以进行有效评估、国际合作程度低、公众参与度不高等问题。建议我国结合履约要求, 与《公约》的目标和精神基本保持一致, 并考虑正在讨论的《2020后全球生物多样性保护框架》, 进一步完善珊瑚礁养护立法、行动计划和气候变化适应方案, 加强综合管理和协调机制建设, 提升海洋保护区的管理实效性, 改进珊瑚礁监测和数据采集, 提升国际合作, 进一步提高公众参与度, 从而不断提升履约能力, 构建更加完善的珊瑚礁养护体系。  相似文献   

17.
Policy makers and managers are increasingly called upon to assess the state of biodiversity, and make decisions regarding potential interventions. Genetic tools are well-recognised in the research community as a powerful approach to evaluate species and population status, reveal ecological and demographic processes, and inform nature conservation decisions. The wealth of genetic data and power of genetic methods are rapidly growing, but the consideration of genetic information and concerns in policy and management is limited by the currently low capacity of decision-makers to access and apply genetic resources. Here we describe a freely available, user-friendly online resource for decision-makers at local and national levels (http://congressgenetics.eu), which increases access to current knowledge, facilitates implementation of studies and interpretation of available data, and fosters collaboration between researchers and practitioners. This resource was created in partnership with conservation practitioners across the European Union, and includes a spectrum of taxa, ecosystems and conservation issues. Our goals here are to (1) introduce the rationale and context, (2) describe the specific tools (knowledge summaries, publications database, decision making tool, project planning tool, forum, community directory), and the challenges they help solve, and (3) summarise lessons learned. This article provides an outlook and model for similar efforts to build policy and management capacity.  相似文献   

18.
We studied the habitat use and mobility of the Grayling butterfly (Hipparchia semele) and the Blue-Winged Grasshopper (Oedipoda caerulescens), two threatened insects within spatially structured blond and grey dunes in a nature reserve along the Belgian coast. Although both species occur in the same biotope, H. semele were more abundant in open, dynamic sites with a relatively high amount of bare sand, while O. caerulescens preferred sheltered, more stable environments with a lower amount of bare sand. Unlike H. semele, substrate use varied in accordance to body colouration in O. caerulescens, especially on cold days, with light-coloured animals being more abundant on sand and dark-coloured animals more abundant on moss. During a mark-recapture-study, we marked 493 Grayling butterflies and 1289 Blue-Winged Grasshoppers. On average, both sexes of H. semele were equally mobile (about 150 m/day; maximum recorded distance of about 1700 m) while male O. caerulescens were significantly more mobile than females (daily average 47 vs. 5 m; maximum distances observed for O. caerulescens were about 800 m). The importance of habitat heterogeneity (within and among patches) and the consequences of habitat use and mobility of both species for the conservation of typical coastal dune habitats are discussed. The complementary use of species-specific information to site-based management measures is advocated.  相似文献   

19.
We compared potential denitrification and phosphorus (P) sorption in restored depressional wetlands, restored riparian buffers, and natural riparian buffers of central Ohio to determine to what extent systems restored under the U.S. Department of Agriculture's Wetland Reserve Program (WRP) and Conservation Reserve Program (CRP) provide water quality improvement benefits, and to determine which practice is more effective at nutrient retention. We also measured soil nutrient pools (organic C, N, and P) to evaluate the potential for long‐term C sequestration and nutrient accumulation. Depressional wetland soils sorbed twice as much P as riparian soils, but had significantly lower denitrification rates. Phosphorus sorption and denitrification were similar between the restored and natural riparian buffers, although all Natural Resources Conservation Service (NRCS) practices had higher denitrification than agricultural soils. Pools of organic C (2570–3320 g/m2), total N (216–243 g/m2), and total P (60–71 g/m2) were comparable among all three NRCS practices but were greater than nearby agricultural fields and less than natural wetlands in the region. Overall, restored wetlands and restored and natural riparian buffers provide ecosystem services to the landscape that were lost during the conversion to agriculture, but the delivery of services differs among conservation practices, with greater N removal by riparian buffers and greater P removal by wetlands, attributed to differences in landscape position and mineral soil composition. At the landscape, and even global level, wetland and riparian restoration in agricultural landscapes will reintroduce multiple ecosystem services (e.g. C sequestration, water quality improvement, and others) and should be considered in management plans .  相似文献   

20.
The Chinese water deer (Hydropotes inermis inermis) is endemic to China. Historically, the species was widely distributed, but now, habitat loss and poaching have reduced its range and number drastically. In order to provide useful information for its conservation, we have investigated the genetic diversity and population structure of the Chinese water deer by analyzing the 403 bp fragment of the mitochondrial DNA (mtDNA) control region (D-loop). Eighteen different haplotypes were detected in 40 samples. Overall, Chinese water deer have a relatively high-genetic diversity compared to other rare cervid species, with a haplotype diversity of 0.923±0.025 and nucleotide diversity of 1.318 ± 0.146%. No obvious phylogenetic structure among haplotypes was found for samples of different origin. An analysis of molecular variance (AMOVA) showed significant differentiation between the Zhoushan and the mainland population (FST= 0.088, P < 0.001; Φ ST = 0.075, P = 0.043), which suggests that exchanges of individuals between Zhoushan and the mainland should be avoided. We also recommend that a breeding center be set up for the mainland population.  相似文献   

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