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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]

We analyse the short‐ and long‐term consequences for atmospheric greenhouse gas (GHG) concentrations of forest management strategies and forest product uses in Sweden by comparing the modelled consequences of forest resource use vs. increased conservation at different levels of GHG savings from carbon sequestration and product substitution with bioenergy and other forest products. Increased forest set‐asides for conservation resulted in larger GHG reductions only in the short term and only when substitution effects were low. In all other cases, forest use was more beneficial. In all scenarios, annual carbon dioxide (CO2) sequestration rates declined in conservation forests as they mature, eventually approaching a steady state. Forest set‐asides are thus associated with increasing opportunity costs corresponding to foregone wood production and associated mitigation losses. Substitution and sequestration rates under all other forest management strategies rise, providing support for sustained harvest and cumulative mitigation gains. The impact of increased fertilization was everywhere beneficial to the climate and surpassed the mitigation potential of the other scenarios. Climate change can have large—positive or negative—influence on outcomes. Despite uncertainties, the results indicate potentially large benefits from forest use for wood production. These benefits, however, are not clearly linked with forestry in UNFCCC reporting, and the European Union's Land Use, Land‐Use Change and Forestry carbon accounting, framework may even prevent their full realization. These reporting and accounting frameworks may further have the consequence of encouraging land set‐asides and reduced forest use at the expense of future biomass production. Further, carbon leakage and resulting biodiversity impacts due to increased use of more GHG‐intensive products, including imported products associated with deforestation and land degradation, are inadequately assessed. Considerable opportunity to better mobilize the climate change mitigation potential of Swedish forests therefore remains. [ABSTRACT FROM AUTHOR]

Many global climate change mitigation pathways presented in IPCC assessment reports rely heavily on the deployment of bioenergy, often used in conjunction with carbon capture and storage. We review the literature on bioenergy use for climate change mitigation, including studies that use top‐down integrated assessment models or bottom‐up modelling, and studies that do not rely on modelling. We summarize the state of knowledge concerning potential co‐benefits and adverse side effects of bioenergy systems and discuss limitations of modelling studies used to analyse consequences of bioenergy expansion. The implications of bioenergy supply on mitigation and other sustainability criteria are context dependent and influenced by feedstock, management regime, climatic region, scale of deployment and how bioenergy alters energy systems and land use. Depending on previous land use, widespread deployment of monoculture plantations may contribute to mitigation but can cause negative impacts across a range of other sustainability criteria. Strategic integration of new biomass supply systems into existing agriculture and forest landscapes may result in less mitigation but can contribute positively to other sustainability objectives. There is considerable variation in evaluations of how sustainability challenges evolve as the scale of bioenergy deployment increases, due to limitations of existing models, and uncertainty over the future context with respect to the many variables that influence alternative uses of biomass and land. Integrative policies, coordinated institutions and improved governance mechanisms to enhance co‐benefits and minimize adverse side effects can reduce the risks of large‐scale deployment of bioenergy. Further, conservation and efficiency measures for energy, land and biomass can support greater flexibility in achieving climate change mitigation and adaptation. [ABSTRACT FROM AUTHOR]

Biofuels policies induce land use changes (LUC), including cropland expansion and crop switching, and this in turn alters water and soil management practices. Policies differ in the extent and type of land use changes they induce and therefore in their impact on water resources. We quantify and compare the spatially varying water impacts of biofuel crops stemming from LUC induced by two different biofuels policies by coupling a biophysical model with an economic model to simulate the economically viable mix of crops, land uses, and crop management choices under alternative policy scenarios. We assess the outputs of an economic model with a high-resolution crop-water model for major agricultural crops and potential cellulosic feedstocks in the US to analyze the impacts of three alternative policy scenarios on water balances: a counterfactual ‘no-biofuels policy’ (BAU) scenario, a volumetric mandate (Mandate) scenario, and a clean fuel-intensity standard (CFS) scenario incentivizing fuels based on their carbon intensities. While both biofuel policies incentivize more biofuels than in the counterfactual, they differ in the mix of corn ethanol and advanced biofuels from miscanthus and switchgrass (more corn ethanol in Mandate and more cellulosic biofuels in CFS). The two policies differ in their impact on irrigated acreage, irrigation demand, groundwater use and runoff. Net irrigation requirements increase 0.7% in Mandate and decrease 3.8% in CFS, but in both scenarios increases are concentrated in regions of Kansas and Nebraska that rely upon the Ogallala aquifer for irrigation water. Our study illustrates the importance of accounting for the overall LUC and shifts in agricultural production and management practices in response to policies when assessing the water impacts of biofuels. [ABSTRACT FROM AUTHOR]

Abstract: Brazil is one of the major contributors to land‐use change emissions, mostly driven by agricultural expansion for food, feed, and bioenergy feedstock. Policies to avoid deforestation related to private commitments, economic incentives, and other support schemes are expected to improve the effectiveness of current command and control mechanisms increasingly. However, until recently, land tenure was unknown for much of the Brazilian territory, which has undermined the governance of native vegetation and challenged support and incentive mechanisms for avoiding deforestation. We assess the total extent of public governance mechanisms protecting aboveground carbon (AGC) stocks. We constructed a land tenure dataset for the entire nation and modeled the effects and uncertainties of major land‐use acts on protecting AGC stocks. Roughly 70% of the AGC stock in Brazil is estimated to be under legal protection, and an additional 20% is expected to be protected after areas in the Amazon with currently undesignated land undergo a tenure regularization. About 30% of the AGC stock is on private land, of which roughly two‐thirds are protected. The Cerrado, Amazon, and Caatinga biomes hold about 40%, 30%, and 20% of the unprotected AGC, respectively. Effective conservation of protected and unprotected carbon will depend on successful implementation of the Forest Act, and regularization of land tenure in the Amazon. Policy development that prioritizes unprotected AGC stocks is warranted to promote conservation of native vegetation beyond the legal requirements. However, different biomes and land tenure structures may require different policy settings considering local and regional specifics. Finally, the fate of current AGC stocks relies upon effective implementation of command and control mechanisms, considering that unprotected AGC in native vegetation on private land only accounts for 6.5% of the total AGC stock. [ABSTRACT FROM AUTHOR]

Bioenergy deployment offers significant potential for climate change mitigation, but also carries considerable risks. In this review, we bring together perspectives of various communities involved in the research and regulation of bioenergy deployment in the context of climate change mitigation: Land-use and energy experts, land-use and integrated assessment modelers, human geographers, ecosystem researchers, climate scientists and two different strands of life-cycle assessment experts. We summarize technological options, outline the state-of-the-art knowledge on various climate effects, provide an update on estimates of technical resource potential and comprehensively identify sustainability effects. Cellulosic feedstocks, increased end-use efficiency, improved land carbon-stock management and residue use, and, when fully developed, BECCS appear as the most promising options, depending on development costs, implementation, learning, and risk management. Combined heat and power, efficient biomass cookstoves and small-scale power generation for rural areas can help to promote energy access and sustainable development, along with reduced emissions. We estimate the sustainable technical potential as up to 100 EJ: high agreement; 100-300 EJ: medium agreement; above 300 EJ: low agreement. Stabilization scenarios indicate that bioenergy may supply from 10 to 245 EJ yr−1 to global primary energy supply by 2050. Models indicate that, if technological and governance preconditions are met, large-scale deployment (>200 EJ), together with BECCS, could help to keep global warming below 2° degrees of preindustrial levels; but such high deployment of land-intensive bioenergy feedstocks could also lead to detrimental climate effects, negatively impact ecosystems, biodiversity and livelihoods. The integration of bioenergy systems into agriculture and forest landscapes can improve land and water use efficiency and help address concerns about environmental impacts. We conclude that the high variability in pathways, uncertainties in technological development and ambiguity in political decision render forecasts on deployment levels and climate effects very difficult. However, uncertainty about projections should not preclude pursuing beneficial bioenergy options. [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]

Does agricultural intensification reduce the area used for agricultural production in Brazil? Census and other data for time periods 1975-1996 and 1996-2006 were processed and analyzed using Geographic Information System and statistical tools to investigate whether and if so, how, changes in yield and stocking rate coincide with changes in cropland and pasture area. Complementary medium-resolution data on total farmland area changes were used in a spatially explicit assessment of the land-use transitions that occurred in Brazil during 1960-2006. The analyses show that in agriculturally consolidated areas (mainly southern and southeastern Brazil), land-use intensification (both on cropland and pastures) coincided with either contraction of both cropland and pasture areas, or cropland expansion at the expense of pastures, both cases resulting in farmland stability or contraction. In contrast, in agricultural frontier areas (i.e., the deforestation zones in central and northern Brazil), land-use intensification coincided with expansion of agricultural lands. These observations provide support for the thesis that (i) technological improvements create incentives for expansion in agricultural frontier areas; and (ii) farmers are likely to reduce their managed acreage only if land becomes a scarce resource. The spatially explicit examination of land-use transitions since 1960 reveals an expansion and gradual movement of the agricultural frontier toward the interior (center-western Cerrado) of Brazil. It also indicates a possible initiation of a reversed trend in line with the forest transition theory, i.e., agricultural contraction and recurring forests in marginally suitable areas in southeastern Brazil, mainly within the Atlantic Forest biome. The significant reduction in deforestation that has taken place in recent years, despite rising food commodity prices, indicates that policies put in place to curb conversion of native vegetation to agriculture land might be effective. This can improve the prospects for protecting native vegetation by investing in agricultural intensification. [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]

Abstract: Growing global population figures and per-capita incomes imply an increase in food demand and pressure to expand agricultural land. Agricultural expansion into natural ecosystems affects biodiversity and leads to substantial carbon dioxide emissions. Considerable attention has been paid to prospects for increasing food availability, and limiting agricultural expansion, through higher yields on cropland. In contrast, prospects for efficiency improvements in the entire food-chain and dietary changes toward less land-demanding food have not been explored as extensively. In this study, we present model-based scenarios of global agricultural land use in 2030, as a basis for investigating the potential for land-minimized growth of world food supply through: (i) faster growth in feed-to-food efficiency in animal food production; (ii) decreased food wastage; and (iii) dietary changes in favor of vegetable food and less land-demanding meat. The scenarios are based in part on projections of global food agriculture for 2030 by the Food and Agriculture Organization of the United Nations, FAO. The scenario calculations were carried out by means of a physical model of the global food and agriculture system that calculates the land area and crops/pasture production necessary to provide for a given level of food consumption. In the reference scenario – developed to represent the FAO projections – global agricultural area expands from the current 5.1billion ha to 5.4billionha in 2030. In the faster-yet-feasible livestock productivity growth scenario, global agricultural land use decreases to 4.8billionha. In a third scenario, combining the higher productivity growth with a substitution of pork and/or poultry for 20% of ruminant meat, land use drops further, to 4.4billionha. In a fourth scenario, applied mainly to high-income regions, that assumes a minor transition towards vegetarian food (25% decrease in meat consumption) and a somewhat lower food wastage rate, land use in these regions decreases further, by about 15%. [Copyright &y& Elsevier]

Abstract: This paper analyses the prospects for establishing afforestation and reforestation Clean Development Mechanism (CDM) projects in Karnataka State, India. Building on multi-disciplinary fieldwork, the aim is to: (i) establish what type of plantations and forests that would best suit a forest-based project activity, considering global climate benefits and local sustainable development objectives; (ii) identify the parameters that are important for ensuring sustainable development at the local level and (iii) develop a transparent ranking tool for the assessment of possible forest-based project activities. Using equal weights for the ranking parameters and a 30-year time horizon, the ranking shows that plantations managed with the shortest rotation period (5 years) would be most suitable for forest-based project activities. However, the performance of individual forest-based project activities will depend on local conditions, which need to be reflected in the weighting procedure. Sensitivity analysis shows that when weights are varied, other forest types can become the preferred option. Based on a combination of the sensitivity analysis and results from the fieldwork, it can be concluded that successful implementation of forest-based project activities will require local participation and are likely to involve multiple forest products and environmental services demanded by the local community. [Copyright &y& Elsevier]

Organically produced food is often considered more environmentally friendly than conventionally produced food, and Germany is one of the most important and rapidly growing markets for organic food in Europe. However, the carbon footprints and land use of organic diets, and how they compare to conventional diets, have not yet been quantified. Using food consumption data from the German National Nutrition Survey II, and carbon footprint and land-use data from life cycle assessment studies of conventional and organic food products, carbon footprints and land use of conventional and organic diets in Germany were calculated for three consumer categories: men, women and their combined unweighted average. Conventional diets are defined as the average diet of consumers who do not buy organic food products; organic diets are the average diets of consumers whose food purchases include a large share of organic food products. Greenhouse gas emissions associated with land use change are not included. The carbon footprints of the average conventional and organic diets are essentially equal (ca. 1250 CO 2 -eq cap −1 year −1 ), while the land use to provide food is ca. 40% greater in the organic diet (ca. 1900 and 2750 m 2 of land cap −1 year −1 in the conventional and organic diets, respectively). The average conventional diet contains 45% more meat than the average organic diet, which on the other hand contains 40% more vegetables, fruits, and legumes (combined). Animal-based food products dominate the carbon footprints and land use (ca. 70–75%) in both diets. The organic diet, in particular that of women, is more aligned with health-based dietary guidelines. Diet-related carbon footprints and land use can be reduced by shifting toward diets with less animal-based food products (other measures are also discussed). General conclusions about the overall performance of conventional and organic agriculture are not supported by this study since only carbon footprints and land use were assessed, while other important issues, such as biodiversity, ecotoxicity impacts and animal welfare, were not considered. [ABSTRACT FROM AUTHOR]

The 2012 revision of the Brazilian Forest Act changed the relative importance of private and public governance for nature conservation and agricultural production. We present a spatially explicit land-use model for Brazilian agricultural production and nature conservation that considers the spatial distribution of agricultural land suitability, technological and management options, legal command, and control frameworks including the Atlantic Forest Law, the revised Forest Act, and the Amazonian land-titling, "Terra Legal," and also market-driven land use regulations. The model is used to analyze land use allocation under three scenarios with varying priorities among agricultural production and environmental protection objectives. In all scenarios, the legal command and control frameworks were the most important determinants of conservation outcomes, protecting at least 80% of the existing natural vegetation. Situations where such frameworks are not expected to be effective can be identified and targeted for additional conservation (beyond legal requirements) through voluntary actions or self-regulation in response to markets. All scenarios allow for a substantial increase in crop production, using an area 1.5-2.7 times the current cropland area, with much of new cropland occurring on current pastureland. Current public arrangements that promote conservation can, in conjunction with voluntary schemes on private lands where conversion to agriculture is favored, provide important additional nature conservation without conflicting with national agricultural production objectives. [ABSTRACT FROM AUTHOR]

Bioenergy aims to reduce greenhouse gas (GHG) emissions and contribute to meeting global climate change mitigation targets. Nevertheless, several sustainability concerns are associated with bioenergy, especially related to the impacts of using land for dedicated energy crop production. Cultivating energy crops can result in synergies or trade-offs between GHG emission reductions and other sustainability effects depending on context-specific conditions. Using the United Nations Sustainable Development Goals (SDGs) framework, the main synergies and trade-offs associated with land use for dedicated energy crop production were identified. Furthermore, the context-specific conditions (i.e., biomass feedstock, previous land use, climate, soil type and agricultural management) which affect those synergies and trade-offs were also identified. The most recent literature was reviewed and a pairwise comparison between GHG emission reduction (SDG 13) and other SDGs was carried out. A total of 427 observations were classified as either synergy (170), trade-off (176), or no effect (81). Most synergies with environmentally-related SDGs, such as water quality and biodiversity conservation, were observed when perennial crops were produced on arable land, pasture or marginal land in the 'cool temperate moist' climate zone and 'high activity clay' soils. Most trade-offs were related to food security and water availability. Previous land use and feedstock type are more impactful in determining synergies and trade-offs than climatic zone and soil type. This study highlights the importance of considering context-specific conditions in evaluating synergies and trade-offs and their relevance for developing appropriate policies and practices to meet worldwide demand for bioenergy in a sustainable manner. • Synergies and trade-offs between SDGs from land use for bioenergy. • Synergies are related to water quality, soil quality and biodiversity conservation. • Trade-offs are related to water availability, food security and revenue. • Previous land use and feedstock are more relevant than other context conditions. [ABSTRACT FROM AUTHOR]

Abstract: The current hot debate on biofuels calls for a balanced and realistic long-term strategy for biofuels. The REFUEL project provides several ingredients for such a strategy. Analyses in this project indicate that domestically produced biofuels can cover a significant share of EU fuel demand in the coming decades, with the EU-12 new member states and Ukraine as most promising regions. This potential can be realised with residual streams and on existing agricultural land, without conversion of e.g. nature reserves. Second generation biofuels are essential for the long-term success of biofuels due to their superior performance in many ways. But generally, the key challenge for the near future would be how to enhance the development of biofuels in a responsible way, i.e. stimulating the production chains with the best performance, and preventing negative impacts e.g., by paying careful attention to possible system impacts of biofuel production such as indirect land use changes and rising food prices. Finally, 2nd generation biofuels require specific policy: the precursor role of 1st generation is overrated, both in technical terms as well as in their role as market precursors. When it comes to synergies, 2nd generation biofuels might benefit more from other developments in the energy sector, such as initiatives in co-firing of biomass for (heat and) power, than from 1st generation biofuels, also because of the public resistance that the latter induce. [Copyright &y& Elsevier]

Abstract: Europe''s agricultural land (including Ukraine) comprise of 164 million hectares of cultivated land and 76 million hectares of permanent pasture. A “food first” paradigm was applied in the estimations of land potentially available for the production of biofuel feedstocks, without putting at risk food supply or nature conservation. Three land conversion scenarios were formulated: (i) A base scenario, that reflects developments under current policy settings and respects current trends in nature conservation and organic farming practices, by assuming moderate overall yield increases; (ii) an environment oriented scenario with higher emphasis on sustainable farming practices and maintenance of biodiversity; and (iii) an energy oriented scenario considering more substantial land use conversions including the use of pasture land. By 2030 some 44–53 million hectares of cultivated land could be used for bioenergy feedstock production. The energy oriented scenario includes an extra 19 million hectares pasture land for feedstocks for second-generation biofuel production chains. Available land is foremost to be found in Eastern Europe, where substantial cultivated areas can be freed up through sustainable gains in yield in the food and feed sector. Agricultural residues of food and feed crops may provide an additional source for biofuel production. When assuming that up to 50% of crop residues can be used without risks for agricultural sustainability, we estimate that up to 246Mt agricultural residues could be available for biofuel production, comparable to feedstock plantations of some 15–20 million hectares. [Copyright &y& Elsevier]