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ions to encourage landowners, both farmers and non-farmers to manage their hedgerows more effectively; these grants are available to pay for gapping up, hedge laying or coppicing.

Small mammals in pastoral land are largely confined to hedgerows or other non-crop features and are therefore particularly vulnerable to intensification (Bates and Harris, 2009). Small mammal species constitute the main prey biomass for a number of species of mammals and birds, and therefore small mammal abundance directly influences the abundance and diversity of predator species contributing to the complexity of local food webs (Korpimaki and Norrdahl, 1991).

There remains some debate on the importance of linear habitats for small mammals, with some suggesting that they cannot support viable populations, that those found in hedgerows are ‘sink’ populations (Tattersall et al. 2004). However, there is evidence that small mammal abundance and diversity does not depend on the linear or non-linear character of the habitat and that linear habitats can support viable populations (Gelling et al. 2007). Thus, in large expanses of uninhabitable grassland, field boundary hedgerows are of great importance for maintaining small mammal populations in an agricultural landscape, but differing farming practices can lead to a huge variety in the quality of these habitats

As the emphasis of farming has shifted there have been a number of agri-environment schemes introduced across Europe with the aim of reversing the effects of previous intensification and enhancing agricultural land for wildlife (Kleijn and Sutherland, 2003). The UK introduced a new set of farming standards in 2005 with farmers now guaranteed subsidy payments, known as ‘cross-compliance’, as long as they follow a set of prescribed conditions aimed at improving the environmental value of their farms. A compulsory code of good practice will preclude farming land within 2 m of the centre of a hedge (DEFRA, 2005a). 

Beyond cross-compliance subsidies, farmers can also apply to put their farmland into Environmental Stewardship (ES). ES is a tiered system, with Entry-Level ES designed to allow most farmers access to the payments by compiling a farm management plan that aims to improve the features of their farm for wildlife and to maintain/improve the scenic value of the British countryside. The enhanced hedgerow management option within ES requires that the farmer cut the hedge no more than once every 2 years, that hedgerows are cut during the winter and that cutting be staggered across the farm. The combined aim of these prescriptions is to ensure that at least some of the hedgerow is allowed to flower every summer (Defra, 2005b).

Properly managed hedgerows are valuable features, playing a key role in enhancing the wildlife value of farmland. Flowering hedgerows are an important source of food and shelter for a number of birds (Hinsley and Bellamy, 2000). Studies suggest that the ES schemes will have a beneficial effect, mainly for taxa such as invertebrates and birds (Kleijn and Sutherland 2003), Whittingham (2007) emphasizes the importance of monitoring the effects of ES to ensure that the scheme’s prescriptions meet the needs of a greater range of species. It is 本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。