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1.
RANDALL, R. E., 1989. Shingle habitats in the British Isles . Shingle is the term applied to sediments larger in diameter than sand but smaller than boulders. Around Great Britain there are almost 900 km of pure shingle and vast stretches of rock/shingle, sand/shingle and mud/shingle mixtures. Outside Japan, New Zealand and north-west Europe, shingle is an uncommon coastal sediment. Shingle may form fringing beaches, spits, bars, cuspate forelands and offshore barrier islands, depending upon available supply of sedimentary material and coastal topography.
Species composition on shingle features is partly determined by climate which affects the geographic range of certain species. The other major factors are beach stability and beach composition. Climate results in distinctive patterns in the flora but within the each climate zone beach movement will affect the quantity of annuals, short-lived or long-lived perennials present. The presence or absence and nature of the fine material within the shingle will cause different combinations of species ecologically related to those of sand dunes, salt-marsh or cliff. Coastal shingle vegetation has a distinctive flora which contains several rare or declining species as well as some common coastal and ruderal plants.
At the largest shingle sites a successional sequence can be recorded which initiates with halophytic forbs near the foreshore and moves through neutral to acid grassland species with shrubs and prostrate scrub in the more inland areas.  相似文献   

2.
FERRY, B. W., BARLOW, S. L. & WATERS, S. J. P., 1989. The shingle ridge succession at Dungeness . The range of plant communities which have colonized both intact shingle ridges and areas of disturbed shingle on Denge Beach, Dungeness, are described. An attempt is made to place these communities into categories of the National Vegetation Classification scheme, and further to relate them to physical and chemical gradients and variations in the shingle substrate.  相似文献   

3.
Nature conservation has a higher probability of being successful when it is backed by public support. This is influenced by knowledge and values, many of which may derive from school curricula, experiments and activities. We implemented a study in a Portuguese Junior High School aiming to evaluate: (1) which factors influence how people subscribe reasons for conserving nature; (2) the criteria used to identify conservation priority species; and, (3) the proposed recovery measures for priority species. A survey of 91 students in a suburban area revealed that nature conservation was regarded as being more important than tourism or industry, but less than values related to public health. Students who have close contacts with wildlife and whose parents have higher education levels exhibited positive attitudes towards nature conservation, which seems to derive from exposure to information related to nature, in their home environment. The criteria chosen to identify conservation priority species and to select appropriate conservation measures indicate that they are likely to be influenced by the media. These results emphasise that the relationship between parental education levels and access to information is an important factor in shaping urban students’ attitudes towards nature conservation.  相似文献   

4.
The breeding habitat preferences of Kentish Plover and Little Ringed Plover were studied on a shingle bed. The location of each nest was measured as the distance to the sea wall, nearest pond and nearest path. The habitat surrounding nests was measured at radii of 0.15 m and 15 m as the proportional cover of shingle, gravel, sand, live and dead vegetation. When all variables were considered simultaneously, the differences between the habitats used by the species were related to the cover of shingle within 15 m of the nest and the distance to the sea wall. Nest sites located close to the sea wall and with high shingle cover almost always belonged to Kentish Plover, while those more distant and with low shingle cover almost always belonged to Little Ringed Plover. Kentish Plover nested in areas of newly exposed shingle, while Little Ringed Plovers used areas which had been stable for longer and hence were colonized by vegetation. This study suggests that management which maintains a high proportion of exposed substrate on shingle beds will increase their suitability for Kentish Plover.  相似文献   

5.
The relationships between geomorphological vulnerability, recreational quality and heritage at beaches in the Canary Islands (Spain) are studied using three sets of indicators. Processes and their interactions are analysed at urban, semi-urban and natural beaches. Natural, cultural and landscape heritage acts as an attractor of recreational activity, which has intensified significantly on Canarian beaches in recent decades. Overcrowding has negatively impacted conservation of the natural and cultural heritage of the beaches, and has increased human pressure, leading to an increase in geomorphological susceptibility. The resulting reduction in geomorphological resilience has had a negative impact on beach facilities. Despite this common pattern, the relationships between these processes have particularities associated with the different types of beach (urban, semi-urban and natural). In order to establish new priorities in coastal public policy, these beach diagnoses and indices should be discussed and debated by the different actors involved in beach management.  相似文献   

6.
The European policy for river management during peak discharge periods is currently changing from exclusion strategies (reinforcement of dykes) to allowing a more natural situation by creating more floodplain space to reduce water levels during peak discharges. In addition, water retention and water storage areas have been created. The new measures are generally being combined with nature development strategies. Up till now, however, ecological targets of broadscale floodplain wetland restoration including sedge marshes, species-rich floodplain forests and carrs, riparian mesotrophic grasslands and other biodiverse riverine ecosystems, have hardly developed in these areas. Most studies on the conditions needed for sustainable ecological development of floodplains have focused on hydrological and geomorphological rather than biogeochemical issues (including nutrient availability and limitation). There are, however, large differences in the composition of river water and groundwater and in sediment quality between rivers in densely populated areas and those in more pristine areas, which serve as a reference. It is very likely that these factors, in combination with heavily altered hydrological regimes and the narrow areas confined between the dykes on both sides of the rivers, impose major constraints on sustainable ecological development of riverine areas. Another issue is that existing wetlands are generally considered to be very appropriate for water retention and conservation, although recent research has shown that this may pose a serious threat to their biodiversity. The present paper reviews the biogeochemical constraints on the combination of floodplain rehabilitation, water conservation and the conservation and development of wetlands. It is concluded that biogeochemical problems (mainly related to eutrophication) predominantly arise in less dynamic parts of the river system, to which the flood-pulse concept applies less. Sound knowledge of the biogeochemical processes involved will contribute to greater efficiency and a better prediction of the opportunities for restoration and development of riverine wetlands. This information can be directly applied in nature management, water management, policy-making and consultancy.  相似文献   

7.
This paper deseribes the criteria important for the successful construction of brackish lagoonal habitats in the UK, as appropriate to creative conservation. These criteria are also of value for the optimal management of existing lagoons. The priority for these criteria is the maintenance of conditions appropriate to the successful survival of the specialist communities and rare species of natural lagoons, with high diversity of these species considered as advantageous.The lagoon should be as large as space and proposed land use will allow, and if greater than 5 ha, should have a high shoreline-length to area ratio. The design and management of water inlets should aim at maintaining a salinity approaching full ambient levels, preferably above 20%.; a fresh-water input is not necessary, but on a small scale would increase diversity. Water depth should be mainly of 1m or less. Saline water input is ideally achieved via a sluice or weir, or a culvert or pipeline through shingle, set such that water enters the lagoon at a level a little below heap tide high water level. Management of the lagoon should be minimal, but would include clearance of encroaching terrestrial plants and protection from pollutant impacts and vandalism. Maintenance of the lagoon water is paramount.  相似文献   

8.
喀斯特峰丛洼地生态系统服务空间权衡度及其分异特征   总被引:4,自引:0,他引:4  
高江波  左丽媛  王欢 《生态学报》2019,39(21):7829-7839
我国西南喀斯特峰丛洼地区脆弱的生态环境与剧烈的人类活动导致石漠化现象以及生态功能退化,制约了区域生态-福祉耦合效益的提升。首先从数值变化与空间变异综合的角度,构建了融合均方根偏差法与地理探测器的生态系统服务空间权衡度指标,进而围绕喀斯特水源涵养-土壤侵蚀关系以及植被固碳-土壤侵蚀关系,在不同环境因子梯度下和地貌形态类型区内开展生态系统服务空间权衡度计算及其分异特征研究。环境因子梯度分析表明,由于植被显著的保持水土能力,水源涵养与土壤侵蚀之间的空间权衡度随植被覆盖度的增大而逐渐减小;地形因子对地表水土过程与植被功能影响深刻,植被固碳和土壤侵蚀之间的空间权衡度随海拔和坡度的升高而逐渐增大,1000 m以上中海拔以及陡坡地区的空间权衡度是低海拔与缓坡地区的4-6倍。地貌形态类型区的统计结果显示,地貌特征对生态系统服务之间的空间权衡关系具有宏观控制作用,植被固碳-土壤侵蚀之间的空间权衡度随地形起伏度的升高而逐渐增大,具体为:中海拔平原 < 中海拔台地 < 中海拔丘陵 < 小起伏中山 < 中起伏中山,水源涵养与土壤侵蚀之间则成相反趋势。因此,今后在以生态系统服务协同提升为目标的喀斯特石漠化治理工作中,应强调环境因子作用程度的空间差异以及地貌形态特征的宏观控制作用。  相似文献   

9.
邬建国 《生态学杂志》1992,3(3):286-288
日益加剧的人类干扰和景观破碎化已危及全球的生物多样性。自然保护成为人类所面临的最重要也最富有挑战性的任务。指导这一实践的理论和原则极为需要。本文试图综述与自然保护科学有关的几个学科在理论和实际研究(尤其是模型)方面的近期成果以及发展趋势,从而提出自然保护模型的发展方向。文中涉猎基于不同方法论、不同组织水平的模型,并对数学模型在自然保护科学中的作用和实用性加以讨论。  相似文献   

10.
数学模型与自然保护科学   总被引:6,自引:1,他引:5  
日益加剧的人类干扰和景观破碎化已危及全球的生物多样性。自然保护成为人类所面临的最重要也最富有挑战性的任务。指导这一实践的理论和原则极为需要。本文试图综述与自然保护科学有关的几个学科在理论和实际研究(尤其是模型)方面的近期成果以及发展趋势,从而提出自然保护模型的发展方向。文中涉猎基于不同方法论、不同组织水平的模型,并对数学模型在自然保护科学中的作用和实用性加以讨论。  相似文献   

11.
12.
马克明  白雪 《生物多样性》2006,14(3):265-273
生物保护研究已经从保护生物学发展到保护生态学,在社会经济因素对自然保护影响日益广泛深刻的今天,我们应该更加主动地从经济学角度进行生物多样性保护。建立自然保护区是生物多样性就地保护的重要措施之一。目前的自然保护区管理研究基本上是以生物学和生态学为主,缺乏系统的经济学考虑,导致一些自然保护区的管理效果不理想,可持续性受到威胁。本文在回顾生物保护的相关经济学研究的同时,提出保护经济学的概念和研究框架,以期为自然保护区的经济管理提供一种新思路,为管理部门的保护投资决策提供支持。  相似文献   

13.
Rosa rugosa Thunb. is one of the dominant and important shrub species in estuary dunes and shingle beaches of northern China. However, its area of distribution, the number of populations, and the size of each population have decreased rapidly in the past two decades because of habitat degradation and loss. Random amplified polymorphic DNA markers were used to determine the genetic diversity of four remaining large natural populations of R. rugosa and to discuss an effective conservation strategy for this endangered species in China. High genetic variations were detected in R. rugosa populations in China. The mean percentage of polymorphic loci (P%) within four local populations was 57.99%, with the P% of the total population being 75.30%. Mean Shannon's information index (H0) was 0.2826, whereas total Ho was 0.3513. The genetic differentiation among populations was 0.1878, which indicates that most genetic diversity occurs within populations. Population Tumenjiang (TMJ) showed the highest genetic diversity (P% = 66.27%; H0 = 0.3117) and contained two exclusive bands. Population Changshandao (CSD) showed higher genetic diversity (P% =59.04%; H0 = 0.3065). Populations TMJ and CSD contained 95.33% and 99.33%, respectively, of loci with moderate to high frequency (P〉0.05) of the total population. These results indicate that populations TMJ and CSD should be given priority for in situ conservation and regarded as seed or propagule sources for ex situ conservation. The results of the present study also suggest that R. rugosa in China has become endangered as a result of human actions rather than genetic depression of populations; thus, human interference should be absolutely forbidden in R. rugosa habitats.  相似文献   

14.
The National Trust was founded in 1895 to preserve land and its associated flora, fauna and buildings. The Trust's land holding has since increased to over 220000 ha, of which almost one-third is of high nature conservation value. The protection provided by Trust ownership is particularly important for certain species. In recent years land management for nature conservation has been transferred from volunteers to professional staff and links with other conservation bodies have been developed. A special programme began in 1979 to survey the wildlife of Trust properties. Research is encouraged where it will benefit management. In some areas where traditional management has lapsed the Trust has invested considerable resources into restoring former regimes.  相似文献   

15.
建立自然保护区是生物多样性保护最为直接和有效的方法。开展重要保护物种的科学考察和研究, 评价其就地保护现状, 对区域内实施科学合理的保护与管理具有重要的意义。本文基于文献资料和野外调查, 分析了山西省重点保护野生植物的地理分布及就地保护现状, 结果显示: (1)山西省重点保护野生植物共57种, 其中有49种分布在自然保护区内, 就地保护率为86%; (2)在地理分布上, 晋城、运城、临汾和阳泉4个市的保护区内分布的保护植物种类最多; (3)采用“累计筛选法”共鉴别出6个保护贡献率最高的保护区, 其累计保护贡献率达到86%; (4)总体来说, 山西省重点保护野生植物受到较全面的就地保护, 但仍存在一些保护空缺, 这些保护空缺地的鉴别将为山西省自然保护区的进一步规划提供科学参考。  相似文献   

16.
Protected areas are controversial because they are so important for conservation and because they distribute fortune and misfortune unevenly. The nature of that distribution, as well as the terrain of protected areas themselves, have been vigorously contested. In particular, the relationship between protected areas and poverty is a long-running debate in academic and policy circles. We review the origins of this debate and chart its key moments. We then outline the continuing flashpoints and ways in which further evaluation studies could improve the evidence base for policy-making and conservation practice.  相似文献   

17.
Valuation of Nature in Conservation and Restoration   总被引:10,自引:1,他引:9  
Valuation of nature is an important aspect of nature conservation and restoration. Understanding valuation in a broad sense may contribute to conservation strategies since it may lead to better support from society. In this article we propose a model of valuation with respect to conservation and restoration of nature. According to the model, valuation of nature can be characterized by a “valuation approach,” consisting of ecological, ethical and aesthetic perspectives. Such an approach includes scientific and normative aspects and leads to a particular claim of conservation. In this paper we discuss different perspectives, and accordingly, we sketch three main types of these valuation approaches. Political and policy issues with respect to nature conservation and restoration are considered in terms of this model.  相似文献   

18.
生物多样性保护优先区是我国为加强生物多样性保护划定的重要区域,辽宁省境内目前并无此类优先区,弥补相关缺失具有重要意义。本研究通过对生态系统保护、人类影响和生物多样性保护区划3个准则层7个指标进行计算,依次获得辽宁省生物多样性保护优先区指标值、准则层值和优先区识别综合值,结合辽宁省县(市)行政边界和自然保护区边界数据,确定了辽宁西部和东部生物多样性保护优先区的建议地域范围。其中,辽宁西部生物多样性保护优先区面积为12951 km2,森林覆盖率为53.6%,包括9个省级以上自然保护区,以水土保持作为区域重要生态功能;辽宁东部生物多样性保护优先区面积为20057 km2,森林覆盖率为78.9%,包括8个省级以上自然保护区,以水源涵养作为区域重要生态功能。上述优先区是国家和省级保护物种的集中分布区,也是辽宁省重要生态系统的分布区,亟待开展生物多样性保护工作。  相似文献   

19.
As conservation agents, biologists play a central role in nature preservation as information-gatherers, promoters of environmental education, lobbyists, and members of societies. Consequently, it is important to understand what factors determine their attitudes towards conservation. We aimed to assess which taxa and recovery measures students from biology core courses consider priorities for conservation and to determine the value students associate with conservation compared to other topics. We asked students (n?=?122) from two private universities in São Paulo State, Brazil to fill out an anonymous questionnaire. They highlighted rarity, vanishing habitats and endemism as important criteria in prioritizing species. Carnivores were identified as the most threatened mammals and habitat recovery was deemed to be the most efficient conservation action. Students valued healthcare, cultural heritage and science over conservation. Our results reveal a two-sided perspective of conservation among students from biology core courses; they possess knowledge of conservation issues but are greatly influenced by anthropocentric and utilitarian views of nature.  相似文献   

20.
Summary

Results from the Nature Conservancy Council's Inventory of Ancient Woodland show regional variations in the extent, origin and composition of Scottish woods and the degree to which they are recognized as important sites for nature conservation. Around 14.5% of Scotland is forested but not more than 2% of the land area is ancient woodland. Nearly half of the ancient area has been replanted, mainly with introduced conifers. Thus the area retaining ancient semi-natural woodland covers just 1 % of Scotland. Woodland within Sites of Special Scientific Interest or nature reserves covers 38,154 ha. The majority of this is ancient semi-natural woodland, but 68% of the total ancient semi-natural woodland area is not so protected. The value for nature conservation of many ancient sites has declined because of the extent of replanting and overgrazing. Recent beneficial changes in land use policies and practices need to be continued to prevent further decline in the nature conservation value of these important woods.  相似文献   

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