The more mobile and generalist 'white' butterflies were common everywhere, ranging from 12.52 ± 3.92 per hour in ex-arable SRC to 5.19 ± 1.30 per hour in grassland. The headlands around the SRC plantations supported more butterflies, such as browns and skippers, than control areas. We surveyed the headlands of SRC and control plots for butterflies by walking transects for an hour three times during the summer. Vegetation cover increased by 34% in the first year with, on average, 44% more cover at the crop edge than the crop interior.įigure 2: Number of plant species in the edge and interior of 22 SRC plantations at different growth stages The number of different plant species increased by 39% after one year's growth with, on average, 31% more at the crop edge (see Figure 2). With growth, the proportion of annuals declined and perennials increased. Recently planted/harvested SRC was dominated by annual plants, such as groundsel, fat hen and creeping thistle. We counted the plant species present within each quadrat, and categorised them into annuals and perennials. We sampled vegetation within 1x10 metre quadrats at various distances from the edge of the SRC and control crops during July. Snipe numbers varied between years, with a maximum of 20 birds recorded from a single plot at any one visit.įigure 1: Average number of wintering waders in SRC plantations compared with arable and grass 86% of cut and standing SRC plantations supported woodcock at some point during the winter, and 73% held snipe. In winter, although lapwings were hardly recorded on SRC sites, both snipe and woodcock were three and 20 times, respectively, more common in the SRC (see Figure 1). SRC is harvested approximately every three years and this creates an open habitat which suits these species. However, recently planted or cut SRC supported more skylarks (0.31 ± 0.08 per hectare) and lapwing (0.85 ± 0.25 per hectare) than the arable controls. The arable controls did have more skylarks (0.15 ± 0.03 per hectare) than established SRC, which did not support this species. Crows (0.58 ± 0.16 per hectare) and starlings (0.41 ± 0.16 per hectare) were more abundant in grassland and may be displaced, so SRC could reduce their populations. We found few skylarks on grassland controls (0.09 ± 0.02 per hectare), so SRC would be unlikely to harm their numbers in this habitat. One aim was to determine if birds associated with open farmland would be displaced by planting SRC. Overall there were more bird species in the SRC (6.60 ± 0.30 per visit) than in the controls (2.40 ± 0.19 per visit), both in the SRC and along its edges. Migrant warblers were especially common, with approximately one singing willow warbler per hectare in spring. Finches (0.75 ± 0.07 per hectare), thrushes (0.46 ± 0.05 per hectare), tits (0.64 ± 0.08 per hectare) and warblers (1.08 ± 0.07 per hectare) were all more abundant in the SRC. Once established, SRC plantations rapidly develop into a scrub habitat, and attract a different bird community from arable and grassland. Each of the SRC plantations were paired with arable and grassland controls. Of these, 12 were planted on arable land and 10 on grassland. Since 2005 we have been studying 22 commercially grown willow SRC plantations, linked to the ARBRE renewable energy project in South Yorkshire. Short rotation coppice (SRC) is likely to become a widely grown energy crop. The canopy of SRC attracted a diverse insect fauna.As the crop matured, the headlands of SRC attracted higher numbers of butterflies than the controls. As the SRC crop established, perennials in the ground flora took over from annuals.In winter, snipe and woodcock prefer short rotation coppice crops to arable and grass fields nearby.bioenergy), enhanced the overall value of this phytotechnology. The resulting high aboveground biomass yield, which can be used for other environmental applications ( e.g. We estimated that the willows demonstrated an overall efficiency level of 95% in reducing NH 4-N concentration in the leachate. For a two-year period, 5200 m 3 ha −1 of NH 4-N polluted groundwater were treated with very little environmental risk and high decontamination efficiency, mainly due to the high evapotranspiration rates and nutrient retention, and fast growth of the willow used. Here we report the results of a field trial that used willow short rotation coppice stands to improve the quality of groundwater polluted mainly with ammonia nitrogen (NH 4-N), which is potentially life-threatening to many aquatic organisms. Willows are a highly versatile tree species that may have multiple environmental applications, including bioenergy, green structures, etc.
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