Cereal Field Margins are a Priority Habitat in the UK Biodiversity Action Plan (BAP). The objective for the UK Cereal Field Margin Habitat Action Plan is to maintain, improve and restore, by management, the biodiversity of some 15,000 ha of cereal field margins on appropriate soil types in the UK by 2010. The Agri-environment (AE) Schemes are seen as Defra’s principal mechanism for delivering its share of the target.
A series of options for the management of arable land were initially trialled through the Arable Stewardship (AS) Pilot Scheme. As a result of the evaluation of the AS Pilot Scheme (1998-2000) arable options were introduced to the Countryside Stewardship Scheme (CSS) in 2002. These new arable options, in addition to existing CSS (and in a few cases, notably Breckland, ESA) prescriptions for grass margins and cultivated (‘Rare Arable Weed’) margins provide a range of options for the management of Cereal Field Margins for biodiversity.
This project consists of two phases involving in year 1 a re-evaluation of Arable Stewardship Pilot Area cereal field margin fixed options and conservation headlands, and the development of methodology for a wider survey of field margins under CSS and ESA management, and then in years 2/3 a survey of the value of cereal field margin options in Countryside Stewardship and the Breckland ESA for botanical and invertebrate value.
PHASE 1: To re-assess the relative value of the main fixed options, and conservation headlands, for the maintenance of plant species richness and abundance, conservation of rare arable plants and provision of bumblebee foraging habitat for the two Arable Stewardship Pilot Areas.
The contractor will collect data, based on a sample of each option, to test the following hypotheses:
1. Richness and abundance of Priority, Conservation Concern and other declining arable plants in ASPS Option 4C > 5 > 3B > 3A > conventional cereal crop (list of arable plants to be agreed with the Defra project Team), and that this richness and abundance has increased over time.
2. Plant species richness and abundance in ASPS Option 4C > 5 > 3B > 3A > conventional cereal crop
3. Bumblebee species richness and abundance in ASPS Option 5 > 4C > conventional cereal crop
4. Bumblebee species richness and abundance is correlated with the richness and abundance of plant species (particularly bee-forage plants)
The project should also aim to examine the effects of soil type, the influence of adjacent management options, and for grass or cultivated margins, the influence of management history (e.g. cutting frequency or use of graminicides).
PHASE 2 will be to develop suitable methodology(ies) for a survey of the Breckland ESA uncultivated wildlife strips and the CSS fixed and rotational arable options, to take place in 2004 and 2005 and also to assess the feasibility of a survey to assess the impacts of the schemes at sites of known historic arable plant interest.
The contractor should develop precise methods for resurveying ASPS at the outset of the project. As with the previous AS evaluation, cereal fields not covered by an AE management option must be included as a control so as to allow direct comparison with Scheme options. The methods should allow for comparison with the previous evaluation. However, the methods do not need to be exactly the same as in the previous AS survey. The contractor should propose methods that would also allow comparison with wider data sets such as the Countryside Survey and agree these in advance with the Defra Project Team.
Fieldwork on Arable Stewardship land should be undertaken in summer 2003. An initial report will be produced in December 2003 detailing the findings of the Arable Stewardship Resurvey and suggesting methodologies for a survey of CSS and ESA margins to be undertaken in 2004. The latter surveys will be reported in 2004 and 2005.