Sustainable Arable Farming For an Improved Environment - SAFFIE
		Simon Potts, Duncan Westbury, Ben Woodcock, Alex Ramsay and Stephanie Harris Since the mid 1970s, many farmland birds have suffered a severe decline in population numbers. In particular, it is the farmland specialists that have suffered the greatest losses, such as the skylark, corn bunting and song thrush. As a consequence, Defra now has a Public Service Agreement (PSA) to reverse the long-term decline of this group of birds by 2020. Several of these species have been targeted under the UK's Biodiversity Action Plan The introduction of the Common Agricultural Policy (CAP) in the late 1950s, which focused on the 'optimum utilization of the factors of production' accelerated the uptake of intensive agricultural techniques and brought about many changes in the landscape. In recent years, arable farming has seen a shift from spring cereal cropping to that of winter wheat and, in turn, this has reduced the area of winter stubble which provides an invaluable seed resource for farmland birds The need to fulfil the Public Service Agreement (PSA) and reverse the decline in farmland birds, while retaining high production value on arable farms, presents a major challenge. To support and enhance populations of birds requires the provision of sufficient habitat with high plant and invertebrate biodiversity value, whilst creating this habitat within farms may potentially reduce crop production. The key is therefore to reconcile biodiversity enhancement with farm productivity through the application of novel and innovative habitat management strategies so that both goals can be met. SAFFIE, a 5-year project, aims to provide the high quality science to underpin this objective. Overall Objective: To enhance farmland biodiversity by integrating novel habitat management approaches, both in the crop and non-cropped margins. The project is based on the hypothesis that manipulation of vegetation architecture in the crop and non-crop areas will increase biodiversity and, by enhancing the diversity, abundance and availability of food sources and nesting habitats, farmland birds will benefit. At CÆR, research efforts are focused on the non-cropped field margins, which have been established using three different seed mixtures, enabling the biodiversity value of each to be assessed: (1) typical grass mix, as in Countryside Stewardship, to represent the standard 'cheap mix'; (2) mixture of tussock grass and forbs (to increase ground-dwelling invertebrates); and (3) mixture of fine-leaved grass and forbs (to increase insect diversity). To maximize the biodiversity value of the different species assemblages, the three sowing treatments will be combined factorially with the following vegetation treatments, to be applied in year two: Spring Cut - The application of this treatment in spring is to reduce the abundance of potentially dominant plant species, especially the grasses, thereby providing gaps in the sward for seedling recruitment Soil Disturbance - Scarification of the sward in spring to create 50-60% soil disturbance will open up the sward through the removal of both living and dead vegetation. Consequently, this will provide gaps in the vegetation for further colonisation Application of Fluazifop-p-butyl - Fluazifop-p-butyl (Fusilade Max 125EC, Syngenta) is a selective graminicide that has the potential to reduce grass abundance, which in turn, may reduce competitive exclusion and therefore promote species diversity. Methodology Experimental Design: There are two phases to the work. Phase one explores all three seed mixes and vegetation treatments, while Phase two investigates the 'best' crop and margin treatments identified from Phase one. Phase one is being carried out at three ADAS sites (Boxworth, Gleadthorpe and High Mowthorpe), chosen to represent three different soil types. At each site, treatments will be applied to five replicate margin plots measuring 5 m wide and 30 m in length. With three different seed mixtures and three different management regimes, in total, nine treatments are being investigated. Phase two affords the capacity to investigate further any promising treatments arising from phase one. The aim is to establish field margins at 25 sites on clay soils in England (including a cluster of sites in Scotland) using two of the seed mixes (tussock and fine-grass). This will enable findings from phase one to be consolidated, and furthermore, will provide the opportunity for wider involvement. Data Collection 1. Plants Various vegetation assessment techniques are being used to determine the accessibility of the sward and the availability of seed and invertebrates for farmland birds: Botanical assessments will be performed in each sowing/treatment plot. All species will be identified and assigned a percentage cover value. Percentage bare ground and litter cover within each replicate quadrat will also be recorded The reproductive status of each plant species will be recorded. This will provide an indication of the resources that are available to insects and birds, at that particular time Sward structure will be investigated using two approaches: coarse grain: To determine the spatial heterogeneity of the vegetation within each margin plot with respect to sward surface height, the 'drop disc method' will be used fine grain: To provide a more detailed investigation of sward structure, a point-quadrat frame consisting of 10 drop pins will be used. 2. Invertebrates Six complementary sampling methods are being used to quantify the invertebrate biodiversity under the various management treatments: Vacuum sampling targets a wide range of invertebrates associated with foliage Sweep netting is being used to assess the abundance of those invertebrates known to be important bird food sources (eg insect larvae, Orthoptera and large Diptera) Pitfall traps are being used to collect ground-dwelling invertebrates (many spiders, harvestmen and ground beetles) Baited pan-traps sample the molluscan (slug and snail) communities Soil sampling using heat extraction assesses below-ground fauna The Octet method allows earthworms to be sampled through electrical extraction. Initial Results 1. Plants From data collected during year 1 (2002), it is apparent that distinct plant communities have established in relation to seed mixture. Differences in terms of sward structure and resource availability, especially between sites, are also emerging. 2. Invertebrates Suction sampling, sweep netting, pitfall traps and soil cores have yielded 4,185 samples, equating to 70-80,000 individuals. 5,425 beetles from the September survey have been identified to species and comprised 135 species. Initial results for Boxworth: beetle community structure - ordination indicates that overall community structure is related to vegetation structure, plant species richness, percentage bare ground and plot orientation beetle diversity is negatively correlated with vegetation structure at Boxworth species richness and abundance of Chrysomelids (leaf beetles) is positively correlated with the percentage coverage of bare ground at Boxworth beetle abundance is greatest in the Tussock mix and lowest in the Fine Grass mix 13,544 spiders (Araneae) and 267 harvestmen (Opiliones) were collected in the September survey spider and harvestman abundance is greatest in the Tussock mix spider and harvestman abundance is related to availability of bare ground and vegetation height In conclusion, the sowing treatments are already beginning to produce measurable effects on invertebrate abundance and diversity and hence on bird food availability. Policy Relevance Results from the project will be employed to inform management policy for arable farmland systems, and to meet the PSA to reverse the decline in farmland birds by 2020. Output Results will be published in relevant journals and presented at various conferences. For further information please visit the dedicated SAFFIE project site. Research Partners Sponsors The project is supported by the Defra Sustainable Arable Link (SAL) Programme