ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01112.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01113.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

The concept of ecosystem restoration is gaining momentum in western Europe. This is necessary because in most managed nature reserves one or more of the following processes, which are analogous to those that have led to the dramatic loss of biological diversity in Europe, are still operating: continuing nutrient output, continuing high level of disturbance and fixing the system in some successional stage. This is partly because most management activities have been derived from, or copy, former agricultural practices. The study of natural ecosystems has revealed the key role large herbivores have in maintaining structural diversity in the vegetation and so biological diversity. Because of this they have been used as tools in achieving a variety of conservation goals. Here, various effects large herbivores can have on plant species composition, structural diversity of the vegetation and fauna are briefly reviewed. Attention is given to pasture‐woodlands in southern Europe, which often have a relatively high biological diversity and share some key features with natural ecosystems: very low nutrient input, extensive grazing with large herbivores and the presence of natural tree cover. In a number of European countries attempts are being made to restore normal functioning multi‐(herbivore) species ecosyst

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01114.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Stock grazing is essential in many habitats owned by the National Trust if their nature conservation interests are to be maintained or enhanced. In this review, the benefits of grazing cattle, sheep and other livestock in different habitat types are described, together with constraints imposed by tenancy agreements and difficulties in obtaining the most appropriate animal. The majority of upland heaths, calcareous grasslands and lowland/coastal heaths on Trust land are being grazed satisfactorily. However, the nature conservation interest of parklands is currently being eroded in part because of inappropriate grazing regimes. It is argued that the best use of stock in the future is in extensive grazing regimes.

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01115.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01116.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01117.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01118.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01119.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

The status, ecology and conservation of butterflies in Europe and Britain are reviewed, as a background to the National Trust's past and future contribution to British conservation. Britain has a poor butterfly fauna by European standards, the main areas of endemism and species richness being in the Alps and southern Europe. To date, the main declines among European butterfly populations have occurred across central‐northern Europe, with slightly higher extinction rates in mainland countries than in Britain. The main causes of decline are biotope destruction, the loss of certain species' habitats within surviving semi‐natural biotopes due to changed land management, and a failure by several species to track the patches of their habitat that are still being generated in modern fragmented landscapes. Until recently, most conservation programmes failed to take account of the latter two factors, resulting in many local extinctions of rare butterfly species even in conservation areas. Recent measures have been much more successful; many were first tested on National Trust propert

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01120.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

The National Trust is of paramount importance in the conservation of butterflies in the UK on account of the scale of its land holding and its ability to manage habitats beneficially. Fifty two of the fifty four species currently regarded as resident in Britain occur on Trust land. The Trust has major responsibilities for the conservation of all bar one of the British rarities, and is of special significance in the conservation of the high brown fritillary and heath fritillary, two protected species. The Trust owns some 35 areas (many of which are large) of national importance for butterflies, plus much other property where the butterfly fauna is of regional importance. The Trust is implementing many dynamic projects aimed at conserving rare species, maintains a butterfly site data base and is developing a butterfly population monitoring programme. It is well placed to address the key issue of butterfly conservation on a metapopulation scale. To do this, it must work in partnership with other conservation organizations.

ISSN:0024-4066    

DOI:10.1111/j.1095-8312.1995.tb01121.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY