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It is commonly recognized that large uncertainties exist in modelled biofuel-induced indirect land-use change, but until now, spatially explicit quantification of such uncertainties by means of error propagation modelling has never been performed. In this study, we demonstrate a general methodology to stochastically calculate direct and indirect land-use change ( dLUC and iLUC) caused by an increasing demand for biofuels, with an integrated economic - land-use change model. We use the global Computable General Equilibrium model MAGNET, connected to the spatially explicit land-use change model PLUC. We quantify important uncertainties in the modelling chain. Next, dLUC and iLUC projections for Brazil up to 2030 at different spatial scales and the uncertainty herein are assessed. Our results show that cell-based (5 × 5 km2) probabilities of dLUC range from 0 to 0.77, and of iLUC from 0 to 0.43, indicating that it is difficult to project exactly where dLUC and iLUC will occur, with more difficulties for iLUC than for dLUC. At country level, dLUC area can be projected with high certainty, having a coefficient of variation (cv) of only 0.02, while iLUC area is still uncertain, having a cv of 0.72. The latter means that, considering the 95% confidence interval, the iLUC area in Brazil might be 2.4 times as high or as low as the projected mean. Because this confidence interval is so wide that it is likely to straddle any legislation threshold, our opinion is that threshold evaluation for iLUC indicators should not be implemented in legislation. For future studies, we emphasize the need for provision of quantitative uncertainty estimates together with the calculated LUC indicators, to allow users to evaluate the reliability of these indicators and the effects of their uncertainty on the impacts of land-use change, such as greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Increasing demand for biofuel has intensified land-use change (LUC) for sugarcane (Saccharum officinarum) expansion in Brazil. Assessments of soil quality (SQ) response to this LUC are essential for quantifying and monitoring sustainability of sugarcane production over time. Since there is not a universal methodology for assessing SQ, we conducted a field-study at three sites within the largest sugarcane-producing region of Brazil to develop a SQ index (SQI). The most common LUC scenario (i.e., native vegetation to pasture to sugarcane) was evaluated using six SQI strategies with varying complexities. Thirty eight soil indicators were included in the total dataset. Two minimum datasets were selected: one using principal component analysis (7 indicators) and the other based on expert opinion (5 indicators). Non-linear scoring curves were used to interpret the indicator values. Weighted and non-weighted additive methods were used to combine individual indicator scores into an overall SQI. Long-term conversion from native vegetation to extensive pasture significantly decreased overall SQ. In contrast, conversion from pasture to sugarcane had no significant impact on overall SQ at the regional scale, but site-specific responses were found. In general, sugarcane production improved chemical attributes (i.e., higher macronutrient levels and lower soil acidity); however it has negative effects on physical and biological attributes (i.e., higher soil compaction and structural degradation as well as lower soil organic carbon (SOC), abundance and diversity of macrofauna and microbial activity). Overall, we found that simple, user-friendly strategies were as effective as more complex ones for identifying SQ changes. Therefore, as a protocol for SQ assessments in Brazilian sugarcane areas, we recommend using a small number of indicators (e.g., pH, P, K, Visual Evaluation of Soil Structure -VESS scores and SOC concentration) and proportional weighting to reflect chemical, physical and biological processes within the soil. Our SQ evaluations also suggest that current approaches for expanding Brazilian sugarcane production by converting degraded pasture land to cropland can be a sustainable strategy for meeting increasing biofuel demand. However, management practices that alleviate negative impacts on soil physical and biological indicators must be prioritized within sugarcane producing areas to prevent unintentional SQ degradation over time. [ABSTRACT FROM AUTHOR]

With the growing demands for food and biofuel, new technologies and crop management systems are being used to increase productivity and minimize land-use impacts. In this context, estimates of productivity and the impacts of agriculture management practices are becoming increasingly important. Numerical models that describe the soil-surface-atmosphere interactions for natural and agricultural ecosystems are important tools to explore the impacts of these agronomical technologies and their environmental impacts. However, these models need to be validated by considering the different soil and environmental conditions before they can be widely applied. The process-based terrestrial agricultural version of the Integrated Biosphere Simulator (IBIS) model (Agro-IBIS) has only been calibrated and validated for North American sites. Here, the authors validate the Agro-IBIS results for an experimental soybean site in southern Brazil. At this site, soybean was grown under two different management systems: no tillage (NT) and conventional tillage (CT). The model results were evaluated against micrometeorological, soil condition, and biomass observations made during the soybean growing season. The leaf area index (LAI) was underestimated, approaching the values obtained in the CT crop system, with higher error in the leaf senescence period. The model shows higher skill for daily averages and the diurnal cycle of the energy balance components in the period of high LAI. The soil temperature and moisture were robustly simulated, although the latter is best correlated with the observations made at the CT field. The ecosystem respiration is highly underestimated, causing an overestimation of the cumulative net ecosystem exchange (NEE), particularly at the end of the crop cycle. [ABSTRACT FROM AUTHOR]

We present an analysis of direct land use change (dLUC) resulting from the conversion of semiarid woodlands in Brazil and India to Jatropha curcas, a perennial biofuel crop. The sites examined include prosopis woodlands, managed for woodfuel production under periodic coppicing, in southern India, and unmanaged caatinga woodlands in the Brazilian state of Minas Gerais. The jatropha plantations under consideration include pruned and unpruned stands and ranged from 2 to 4 years of age. Stocks of carbon in aboveground (AG) pools, including woody biomass, coarse debris, leaf litter, and herbaceous matter, as well as soil organic carbon (SOC) were evaluated. The jatropha plantations store 8-10 tons of carbon per hectare (t C ha−1) in AG biomass and litter when managed with regular pruning in both India and Brazil. Unpruned trees, only examined in Brazil, store less biomass (and carbon), accumulating just 3 t C ha−1 in AG pools. The two woodlands that were replaced with jatropha show substantial differences in carbon pools: prosopis contains ∼11 t C ha−1 in AG stocks of carbon, which was very close to the jatropha stand which replaced it. In contrast, caatinga stores ∼35 t C ha−1 in AG biomass. Moreover, no change in SOC was detected in land that was converted from Prosopis to jatropha. As a result, there is no detectable change in AG carbon stocks at the sites in South India where jatropha replaced prosopis woodlands. In contrast, large losses of AG carbon were detected in Central Brazil where jatropha replaced native caatinga woodlands. These losses represent a carbon debt that would take 10-20 years to repay. [ABSTRACT FROM AUTHOR]

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Global energy demand will increase through the twenty-first century. Competition for energy resources has already revealed geopolitical fault lines, and the dependence of industrial economies on fossil fuel promises to keep nations on edge. A widespread consensus has emerged that societies must transition to a new energy basis, given that fossil fuel is nonrenewable and its combustion leads to global warming. Although alternatives like nuclear energy and hydropower provide important electrical supplies locally, the search goes on, and recently much attention has focused on biofuel. Although biofuel represents a renewable and 'green' energy, there is also a downside. This article considers one potential problem, namely, the impact of growing international biofuel demand on Amazonia. The article focuses on Brazil, given the explosive growth of Brazilian agriculture, and notable effects on forests within its national borders. The article seeks to answer this question: How will global demand for Brazil's land-based commodities, including biofuel, impact its tropical forest in the Amazon basin? In attempting to answer this question, the article describes recent agricultural expansion in Brazil and its emergent landscape of renewable energy. Using an adaptation of rent theory, it frames a concept of landscape cascade and shows how Brazil's expanding landscape of renewable energy is impacting forest areas at a great distance. The article then considers recent projections of demand for Amazonian land out to 2020, given growth of Brazilian biofuel production and cattle herds. The projections indicate that more Amazonian land will be demanded than has been made available by Brazilian environmental policy. With this result in mind, the article discusses the discursive dismemberment of Amazonia and how this articulates with efforts by Brazilian politicians to increase the region's land supply. The article points out that agricultural intensification holds the key to meeting global demand without degrading the Amazonian forest, a landscape unique in the world for its ecological and cultural riches. [ABSTRACT FROM AUTHOR]

Abstract: Brazil is experiencing a surge in planting of sugar cane crops driven by internal markets and external policy drivers for biofuels. The current expectation is for the expansion of these crops to continue. This creates concern over the extent to which the full implications of large scale land use change are currently being considered by decision-makers. Using the State of São Paulo as a case study (as it accounts for the majority of sugar cane grown in Brazil), a comparison was made of the impacts identified in Environmental Impact Statements (EISs) and Preliminary Environmental Reports (PERs), which have to be submitted for approval of most new sugar cane activities, with significant impacts known to be associated with sugar cane activities derived from literature review. The results from a review of 32 EISs and PERs (30% of the population) indicated that whilst some impacts were well covered by the sample (water and soil pollution, and air emissions) energy balance and Green House Gas emissions and food security had very limited consideration, and water resources, residues, labour conditions and social responsibility were only partially covered. Environmental Impact Assessment is constrained by its environmental advocacy role and its application to the project level only. This study highlights its limitations in the context of assessment of land use change which demands more strategic consideration. [Copyright &y& Elsevier]

The planned expansion of biofuel plantations in Brazil could potentially cause both direct and indirect land-use changes (e.g., biofuel plantations replace rangelands, which replace forests). In this study, we use a spatially explicit model to project land-use changes caused by that expansion in 2020, assuming that ethanol (biodiesel) production increases by 35 (4) x 109 liter in the 2003-2020 period. Our simulations show that direct land-use changes will have a small impact on carbon emissions because most biofuel plantations would replace rangeland areas. However, indirect land-use changes, especially those pushing the rangeland frontier into the Amazonian forests, could offset the carbon savings from biofuels. Sugarcane ethanol and soybean biodiesel each contribute to nearly half of the projected indirect deforestation of 121,970 km2 by 2020, creating a carbon debt that would take about 250 years to be repaid using these biofuels instead of fossil fuels. We also tested different crops that could serve as feedstock to fulfill Brazil's biodiesel demand and found that oil palm would cause the least land-use changes and associated carbon debt. The modeled livestock density increases by 0.09 head per hectare. But a higher increase of 0.13 head per hectare in the average livestock density throughout the country could avoid the indirect land-use changes caused by biofuels (even with soybean as the biodiesel feedstock), while still fulfilling all food and bioenergy demands. We suggest that a closer collaboration or strengthened institutional link between the biofuel and cattle-ranching sectors in the coming years is crucial for effective carbon savings from biofuels in Brazil. [ABSTRACT FROM AUTHOR]

Biofuels are predicted to constitute a large proportion of fuel consumption in the global transport sector under stringent climate mitigation polices in future. In Brazil, sugarcane ethanol has been widely deployed at large scale and an oriented expansion of sugarcane is considered to be a key measure to ensure the expected positive outcomes from biofuels. In this study, more recent and accurate georeferenced information were combined with an enhanced land use classification system to update the original Sugarcane Agroecological Zoning (SAEZ). We also excluded environmentally relevant areas (ERA) in our updated SAEZ to create a new set of reference maps for supporting future prioritization of areas for sugarcane ethanol expansion. We mapped 41.7 Mha as suitable land for sugarcane expansion in center-south region of Brazil, differently from the 50 Mha indicated in the original SAEZ. After excluding the ERA, 33.7 Mha was found to be suitable for sugarcane expansion, of which 20 Mha is currently occupied with pasture lands. About half of these areas were located in Mato Grosso do Sul and Minas Gerais states and an exploratory assessment of two microregions from these states demonstrated the importance of conducting regional assessments to prioritize the areas for a more sustainable sugarcane expansion to meet future bioenergy demands. • Our analysis identified an area 17% smaller than original agro-ecological zoning suitable for sugarcane expansion. • By excluding environmentally relevant areas, the total suitable area for sugarcane expansion is reduced to 33.7 Mha. • About two thirds of that area is currently occupied with pasture lands. • About half of suitable areas occupied with pasture lands are in two Brazilian states. • Local conditions are fundamental for oriented expansion of bioenergy production. [ABSTRACT FROM AUTHOR]

Latest studies estimate land use intensity of wind-powered electricity around 0.3–1.3 m2 MWh-1 [1]. This is significantly lower compared to biomass-powered electricity, which land use intensity is estimated around 450-800 m2 MWh-1 [1]. Hence, the significant contribution of biomass energy to land-use change, particularly in countries like Brazil, is widely known. In contrary, low land use intensity of wind-powered electricity suggests that contribution of its infrastructure to land-use change is minor. However, some studies point out the potential restriction of land use for human settlements, negative impact on biodiversity [1] and occurring land conflicts [2] due to wind-powered electricity infrastructure. Better knowledge of wind-powered electricity infrastructure impact on land use change require investigation of related land cover patterns. For discovering those patterns, we focus on two major questions:- What land cover is favourable for VRES infrastructure deployment?- What land-use changes follow the VRES infrastructure deployment?Our case study focuses on wind parks deployed during past 25 years in Brazil. For spatiotemporal analysis of land cover patterns in Brazil, we combine annual land-use and land cover time series – available from 1985 to 2017 – with locations of wind generation infrastructure, transmission grids and transportation network [3].Land cover patterns related to wind parks deployment will improve our understanding of its role in current land use change, and allow the assessment of future land use change in case of extensive wind parks deployment. [1] Uwe R. Fritsche et al. „Energy and Land Use". Global Land Outlook Working Paper (2017).[2] C. Brannstrom, A. Gorayeb, J. S. Mendes, C. Loureiro, A. J. A. Meireles, E. V. Silva, A. L. R. Freitas, R.F. Oliveira. Is Brazilian wind power development sustainable? Insights from a review of conflicts in Ceará state. Renewable and Sustainable Energy Reviews (2017), 67, p. 62-71. https://doi.org/10.1016/j.rser.2016.08.047[3] MapBiomas Project - Collection v.3.0 of the Annual Land Use Land Cover Maps of Brazil: http://mapbiomas.org/map#coverage [ABSTRACT FROM AUTHOR]