In order to assess long-term effects on productivity, environmental impacts and soil fertility of contrasting farming practices, six cropping systems, ranging from conventional arable without livestock to organic mixed dairy farming with few arable crops, have been compared since 1989 on a loam soil. A decline in soil structure quality was found in a conventional arable system with annual ploughing with no rotational grass. This system had higher bulk density and mean aggregate size than other systems, and lower levels of plant available water and aggregate stability. Opposite trends were related to the proportion of grass leys in the other systems and to their levels of soil organic matter. The latter declined markedly over 15 years in the conventional arable system, and there were smaller declines in most other systems. In an arable system without ploughing, but with rotary tillage in spring, organic matter was maintained and high structural stability was found. This system had high bulk density, but the proportion of small aggregates equalled that found in systems with ley. There were overall increases in earthworm density (84%), earthworm biomass (80%) and the density of earthworm channels (132%) in the topsoil between 1994 and 2004. Most of these increases were found in systems with 1-3 years of ley in the 4-year rotation. Low values of all earthworm parameters, and only minor changes over the period studied, were found in two non-organic arable systems without ley, indicating high pressure on soil fauna. Lower earthworm activity was found in the non-organic arable system with reduced tillage as compared to the non-organic arable system with annual ploughing. Thus, 50% leys in the rotation appeared desirable for the maintenance of satisfactory soil structure and earthworm activity. Though the deterioration of soil structure in the conventional arable system was not extreme, as the soil was well structured initially, the results may have implications for the sustainability of stockless arable systems on soils with a less favourable initial structure. #

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30In repeatedly mown and mulched green manure leys, the mulched herbage contains substantial amounts of 31 nitrogen (N), which may only slightly contribute to the following crops´ nutrient demand. The objective of the 32 present work was to evaluate the effect of alternative strategies for green manure management on the yield and N 33 recovery of a subsequent spring barley crop, and their short term effects on soil structure and earthworm 34 populations. A field trial was run from 2008 to 2011 at four sites with contrasting soils under cold climate 35 conditions. We compared several options for on-site herbage management and the application of anaerobically 36 digested green manure herbage. Depending on the site, removal of green manure herbage reduced the barley 37 grain yield by 0% to 33% compared to leaving it on-site. Applying digestate, containing 45% of the N in 38 harvested herbage, as fertilizer for barley gave the same yields as when all herbage was mulched the preceding 39 season. Overall, the apparent N recovery was enhanced from 7% when all herbage was mulched, to 16% when 40 returned as digestate. A positive effect on earthworm density and biomass was seen after one season of retaining 41 mulch material, rather than removing it. Digestate did not affect the earthworm population, but contributed to 42 higher soil aggregate stability. In conclusion, for spring barley production after green manure ley, the digestate 80In spring barley, availability of inorganic N at the early tillering stage is a key factor for N uptake and 86alternative strategies appear to be necessary. Application of digestate from green manure foliage digested 87anaerobically in a biogas plant may be a promising option for improving yields and N recovery instead of 88 mulching (Möller and Müller, 2012;Stinner et al., 2008). In biogas plants, the easily degradable organic matter 89

Abstract. Farmland is a major land cover type in Europe and Africa and provides habitat for numerous species. The severe decline in farmland biodiversity of the last decades has been attributed to changes in farming practices, and organic and low-input farming are assumed to mitigate detrimental effects of agricultural intensification on biodiversity. Since the farm enterprise is the primary unit of agricultural decision making, management-related effects at the field scale need to be assessed at the farm level. Therefore, in this study, data were collected on habitat characteristics, vascular plant, earthworm, spider, and bee communities and on the corresponding agricultural management in 237 farms in 13 European and two African regions. In 15 environmental and agricultural homogeneous regions, 6-20 farms with the same farm type (e.g., arable crops, grassland, or specific permanent crops) were selected. If available, an equal number of organic and non-organic farms were randomly selected. Alternatively, farms were sampled along a gradient of management intensity. For all selected farms, the entire farmed area was mapped, which resulted in total in the mapping of 11 338 units attributed to 194 standardized habitat types, provided together with additional descriptors. On each farm, one site per available habitat type was randomly selected for species diversity investigations. Species were sampled on 2115 sites and identified to the species level by expert taxonomists. Species lists and abundance estimates are provided for each site and sampling date (one date for plants and earthworms, three dates for spiders and bees). In addition, farmers provided information about their management practices in face-to-face interviews following a standardized questionnaire. Farm management indicators for each farm are available (e.g., nitrogen input, pesticide applications, or energy input). Analyses revealed a positive effect of unproductive areas and a negative effect of intensive management on biodiversity. Communities of the four taxonomic groups strongly differed in their response to habitat characteristics, agricultural management, and regional circumstances. The data has potential for further insights into interactions of farmland biodiversity and agricultural management at site, farm, and regional scale.

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