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The agriculture sector can contribute to climate change mitigation by reducing its own greenhouse gas (GHG) emissions, sequestering carbon in vegetation and soils, and providing biomass to substitute for fossil fuels and other GHG‐intensive products. The sector also needs to address water, soil, and biodiversity impacts caused by historic and current practices. Emerging EU policies create incentives for cultivation of perennial plants that provide biomass along with environmental benefits. One such option, common in northern Europe, is to include grass in rotations with annual crops to provide biomass while remediating soil organic carbon (SOC) losses and other environmental impacts. Here, we apply a spatially explicit model on >81,000 sub‐watersheds in EU27 + UK (Europe) to explore the effects of widespread deployment of such systems. Based on current accumulated SOC losses in individual sub‐watersheds, the model identifies and quantifies suitable areas for increased grass cultivation and corresponding biomass‐ and protein supply, SOC sequestration, and reductions in nitrogen emissions to water as well as wind and water erosion. The model also provides information about possible flood mitigation. The results indicate a substantial climate mitigation potential, with combined annual GHG savings from soil‐carbon sequestration and displacement of natural gas with biogas from grass‐based biorefineries, equivalent to 13%–48% of current GHG emissions from agriculture in Europe. The environmental co‐benefits are also notable, in some cases exceeding the estimated mitigation needs. Yield increases for annual crops in modified rotations mitigate the displacement effect of increasing grass cultivation. If the grass is used as feedstock in lieu of annual crops, the displacement effect can even be negative, that is, a reduced need for annual crop production elsewhere. Incentivizing widespread deployment will require supportive policy measures as well as new uses of grass biomass, for example, as feedstock for green biorefineries producing protein concentrate, biofuels, and other bio‐based products. [ABSTRACT FROM AUTHOR]

Abstract: The large flow of reactive nitrogen (N) through agriculture causes negative environmental impacts, pointing to a need for changes in agricultural practices. At the same time, agriculture is expected to provide biomass to support the increasing demand from the UK bioenergy sector. A high-level aggregated model of the agricultural system in the UK was developed, which maintains the existing level of food and livestock production and at the same time increases N recirculation. Integrating three different bioenergy sub-systems into the agricultural system was an essential component of the model development. Cellulosic bioenergy crops were located in the landscape as vegetation filters to intercept and capture N and thereby reduce N leaching. Efficient collection and digestion of manure produced organic N fertiliser and biogas. Efficient forage production for cattle allowed further cultivation of bioenergy plants. Five implementation scenarios were developed to clarify the contribution of these bioenergy sub-systems to improved N management. The results point to a significant potential for improving the productive use of reactive N and for decreasing N losses to water and air. The interception and recirculation of N presently leaching from arable fields is assessed as the most important option. It is also important to increase recirculation of N in manure and in bioenergy system by-flows. Besides mitigating the environmental impacts of agriculture these measures reduce the requirements for newly synthesised N fertilisers. A systems perspective on N, agriculture, and bioenergy systems facilitates N recirculation and promotes effective N use, reducing the need for additional N inputs. [Copyright &y& Elsevier]

Abstract: The concept of willow vegetation filters for the treatment of nutrient-rich wastewater has the potential to address two of our most serious environmental problems today —water pollution and climate change— in a cost-efficient way. Despite several benefits, including high treatment efficiency, increased biomass yields, improved energy and resource efficiency, and cost savings, willow vegetation filters have so far only been implemented to a limited degree in Sweden. This is due to various kinds of barriers, which may be the result of current institutional, structural and technical/geographical conditions. This paper discusses the prospects of a more widespread utilisation of willow plantations for wastewater treatment in Sweden, including existing incentives and barriers, based on current knowledge and experience. [Copyright &y& Elsevier]

Bioenergy can contribute to achieving European Union (EU) climate targets while mitigating impacts from current agricultural land use. A GIS-based modeling framework (1000 m resolution) is employed to match biomass supply (forest and agricultural residues, complemented by lignocellulosic energy crops where needed) with biomass demand for either electricity or bio-oil production on sites currently used for coal power in the EU-28, Norway, and Switzerland. The framework matches supply and demand based on minimizing the field-to-gate costs and is used to provide geographically explicit information on (i) plant-gate supply cost; (ii) CO 2 savings; and (iii) potential mitigation opportunities for soil erosion, flooding, and eutrophication resulting from the introduction of energy crops on cropland. Converting all suitable coal power plants to biomass and assuming that biomass is sourced within a transport distance of 300 km, would produce an estimated 150 TW h biomass-derived electricity, using 1365 PJ biomass, including biomass from energy crops grown on 6 Mha. Using all existing coal power sites for bio-oil production in 100-MW pyrolysis units could produce 820 PJ of bio-oil, using 1260 PJ biomass, including biomass from energy crops grown on 1.8 Mha. Using biomass to generate electricity would correspond to an emissions reduction of 135 MtCO 2 , while using biomass to produce bio-oil to substitute for crude oil would correspond to a reduction of 59 MtCO 2. In addition, energy crops can have a positive effect on soil organic carbon in most of the analyzed countries. The mitigation opportunities investigated range from marginal to high depending on location. • A GIS-based method (1000 m) is used to match lignocellulosic biomass demand & supply. • Bioelectricity & biooil production on current sites for coal power are investigated. • Demand is met by biomass from neighboring areas and with lowest field-to-gate cost. • A high bioenergy demand can lead to changes in land use to cultivate energy crops. • Introducing energy crops on croplands results in a positive effect on SOC. [ABSTRACT FROM AUTHOR]

• Substantial potential for mitigating assessed impacts by strategic perennialization. • Highest mitigation potential found for accumulated SOC losses. • Priority areas for strategic perennialization scattered across EU. • Main ''hot spots'': Denmark, western UK, The Po valley in Italy, and the Danube basin. • 10–46% of current annual crops in EU within priority areas. Society faces the double challenge of increasing biomass production to meet the future demands for food, materials and bioenergy, while addressing negative impacts of current (and future) land use. In the discourse, land use change (LUC) has often been considered as negative, referring to impacts of deforestation and expansion of biomass plantations. However, strategic establishment of suitable perennial production systems in agricultural landscapes can mitigate environmental impacts of current crop production, while providing biomass for the bioeconomy. Here, we explore the potential for such "beneficial LUC" in EU28. First, we map and quantify the degree of accumulated soil organic carbon losses, soil loss by wind and water erosion, nitrogen emissions to water, and recurring floods, in ∼81.000 individual landscapes in EU28. We then estimate the effectiveness in mitigating these impacts through establishment of perennial plants, in each landscape. The results indicate that there is a substantial potential for effective impact mitigation. Depending on criteria selection, 10–46% of the land used for annual crop production in EU28 is located in landscapes that could be considered priority areas for beneficial LUC. These areas are scattered all over Europe, but there are notable "hot-spots" where priority areas are concentrated, e.g., large parts of Denmark, western UK, The Po valley in Italy, and the Danube basin. While some policy developments support beneficial LUC, implementation could benefit from attempts to realize synergies between different Sustainable Development Goals, e.g., "Zero hunger", "Clean water and sanitation", "Affordable and Clean Energy", "Climate Action", and "Life on Land". [ABSTRACT FROM AUTHOR]