• Energy Research

Abstract Rising demand for renewable resources has increased silage maize (Zea mays L.) production characterized by intensive soil management, high fertilizer and pesticide inputs as well as simplified crop rotations. Advantages of renewable biomass production may thus be cancelled out by adverse environmental effects. Perennial crops, like cup plant (Silphium perfoliatum L.), are said to benefit arthropods. Substituting silage maize could hence increase biodiversity and foster ecosystem services. This study aimed at comparing the attractiveness of both crops to arthropods, which are either flower-visiting or active in the crop canopy. Further, results were scaled to the landscape level to optimize crop partitioning concerning yields and species diversity. A field experiment with conventionally tilled annual and perennial no-tilled crops was established in 2015 near Munich (Germany). The crops chosen were insect-pollinated cup plant and wind-pollinated maize. Arthropods were sampled between June and September 2016. Four replicated UV-active pan traps, consisting of three bowls each, were used to catch arthropods at the actual crop height on five sampling dates. The collected arthropods were counted and taxonomically determined. In total 3810 individuals (Arachnida: 52; Insecta: 3758) from 9 orders (115 taxonomic groups) were collected. Silage maize mostly showed lower diversity values, indicating higher biodiversity in cup plant. However, the differences were small. Nevertheless, cup plant harbored more pollinators and parasitoids. Finding an optimal combination of both crops based on diversity gains is thus not straightforward. However, integrating cup plant to silage maize production systems allows increasing arthropod diversity by means of moderate yield reduction.

AbstractConversion of semi-natural habitats, such as field margins, fallows, hedgerows, grassland, woodlots and forests, to agricultural land could increase agricultural production and help meet rising global food demand. Yet, the extent to which such habitat loss would impact biodiversity and wild species is unknown. Here we survey species richness for four taxa (vascular plants, earthworms, spiders, wild bees) and agricultural yield across a range of arable, grassland, mixed, horticulture, permanent crop, for organic and non-organic agricultural land on 169 farms across 10 European regions. We find that semi-natural habitats currently constitute 23% of land area with 49% of species unique to these habitats. We estimate that conversion of semi-natural land that achieves a 10% increase in agricultural production will have the greatest impact on biodiversity in arable systems and the least impact in grassland systems, with organic practices having better species retention than non-organic practices. Our findings will help inform sustainable agricultural development.

Life Cycle Assessment (LCA) is a widely used tool to assess environmental sustainability of products. The LCA should optimally cover the most important environmental impact categories such as climate change, eutrophication and biodiversity. However, impacts on biodiversity are seldom included in LCAs due to methodological limitations and lack of appropriate characterization factors. When assessing organic agricultural products the omission of biodiversity in LCA is problematic, because organic systems are characterized by higher species richness at field level compared to the conventional systems. Thus, there is a need for characterization factors to estimate land use impacts on biodiversity in life cycle assessment that are able to distinguish between organic and conventional agricultural land use that can be used to supplement and validate the few currently suggested characterization factors. Based on a unique dataset derived from field recording of plant species diversity in farmland across six European countries, the present study provides new midpoint occupation Characterization Factors (CF) expressing the Potentially Disappeared Fraction (PDF) to estimate land use impacts on biodiversity in the 'Temperate Broadleaf and Mixed Forest' biome in Europe. The method is based on calculation of plant species on randomly selected test sites in the biome and enables the calculation of characterization factors that are sensitive to particular types of management. While species richness differs between countries, the calculated CFs are able to distinguish between different land use types (pastures (monocotyledons or mixed), arable land and hedges) and management practices (organic or conventional production systems) across countries. The new occupation CFs can be used to supplement or validate the few current CF's and can be applied in LCAs of agricultural products to assess land use impacts on species richness in the 'Temperate Broadleaf and Mixed Forest' biome.