The increasing increase in global biofuel production has been observed since 2000. For instance, ethanol production quadrupled between 2002 and 2020 (OECD-2020 & OECD/FAO, 2020). Policies to support biofuels in the largest producing regions are motivated by reducing dependence on foreign oil, as they have also sought to mitigate GHG emissions from the consumption of transport fuels and improve rural economic development (Khanna et al., 2021).

There is a consensus that biomass will play a crucial role in the supply of future products currently derived from crude oil. This indicates a shift towards more sustainable energy sources and materials (Jaiswal et al., 2019). However, challenges remain due to the growing demand for food and animal feed, which could intensify competition for land use, along with the impacts of climate change and the need to protect natural ecosystems (Jaiswal et al., 2017). The following points are particularly important (Gvein et al., 2023):

To contribute to mitigating climate change, the agricultural sector focuses on reducing greenhouse gas (GHG) emissions by implementing practices such as planting biomass on degraded pasturelands. These efforts aim to boost sugarcane-derived biofuel production, adopt land-use change (LUC), and drive habits and customs to enhance soil carbon sequestration. This can help balance the competing demands for land between food and energy production, thereby supporting global food security initiatives (Gvein et al., 2023).

Land-use competition is a determining aspect in assessing the sustainability of biofuels in Brazil (Rutz & Janssen, 2008). Brazil’s focus on sugarcane as a biofuel source began in the 1970s, with the introduction of the Proálcool program aimed at reducing dependence on oil imports. Recently, there has been a growing recognition of the potential for using degraded lands for biomass cultivation. The choice of degraded pasture areas in the state of Mato Grosso for biomass production is particularly relevant, as these areas have been identified for their potential to reduce direct land use change (d-LUC) emissions.

According to the (OECD-2020 & OECD/FAO, 2020), global projections indicate a 13% growth in ethanol production by the year 2030. Brazil processed approximately 26.78 billion liters of ethanol in the 2020/2021 planting period (C.O.N.A.B., 2024). The 2018 introduction of the RenovaBio program marked a pivotal step in promoting biofuels in Brazil. This program establishes market mechanisms to recognize the emissions reduction capacity of biofuels, including the certification of production and the issuance of Decarbonization Credits (CBIO). Recent studies have focused on assessing the carbon balance in degraded areas and the impacts of d-LUC over time (Grangeia et al., 2022).

The problem identified in the study is the variability and uncertainty in sustainability impacts, particularly in relation to the GHG reductions from biomass production on degraded lands. The challenges arise from context-specific conditions such as previous land use and biophysical characteristics, which lead to different outcomes in carbon emissions and sequestration. Additionally, there are uncertainties in estimating the scale and impacts of LUC, especially concerning sugarcane plantations, and the need for tailored, location-specific approaches to effectively manage these challenges. These issues complicate the broader application of findings across regions, making it difficult to generalize results and optimize biomass production strategies for GHG reduction. Neglecting the cultivation of biomass in degraded areas without proper management can increase GHG emissions and prevent the realization of carbon sequestration benefits. This could perpetuate dependence on fossil fuels and contribute to rising carbon footprints.

Ethanol production using low-productivity pastures to grow sugarcane is a sustainable way to expand the sugarcane cultivation area and, therefore, increase the production of bioenergy (Cherubin et al., 2021). Possible alternatives for enhancing carbon sequestration from the atmosphere encompass: expanding the production of bioproducts through industrial means, capturing carbon in sugarcane plantations, promoting the use of biofuels, advancing technological and industrial processes for negative emissions, and recycling agricultural waste (Cerri et al., 2022).

The implementation of LUC can yield immediate benefits and long-term improvements in soil health and carbon sequestration [(Mello et al. 2014);(Cerri et al., 2022)].

On a global scale, unresolved issues in biomass production can affect Brazil's role in global climate change mitigation efforts. As a significant player in the biofuel market, Brazil's failure to optimize biomass production could undermine international commitments to reduce greenhouse gas emissions and achieve sustainability goals. Several studies have contributed to the understanding and greater acceptance of the environmental impacts of biomass production, not only in terms of land use change and carbon sequestration but also particularly in the context of Brazilian agricultural practices [(Novaes et al., 2017); (Donke et al., 2020); (Gvein et al., 2023); (He et al., 2024)].

There is a growing consensus on the importance of using degraded lands for biomass production. Studies indicate that shifting arable land to the cultivation of perennial energy crops can increase water use efficiency and significantly reduce GHG emissions. Although biomass production for biofuels offers promising opportunities, if not managed carefully, it can also pose significant risks. LUC represents a large contribution to global CO₂ emissions (IPCC, 2014 apud (Novaes et al., 2017)). Predicting the scale and impacts of sugarcane plantations is fundamental, especially in Brazilian states with extensive agricultural areas and varied emission profiles. States in the southern and central-western regions generally have low associated emissions, while those within the Amazon biome have the highest CO₂ emission rates, mainly due to the expansion of grain plantations (Novaes et al., 2017).

The analysis considered geographically detailed land conversion data and comprised the assessment of emissions resulting from d-LUC, as described by (Novaes et al., 2017). The data was updated based on research conducted by (Donke et al., 2020) taking into consideration the impact of d-LUC over 20 years. This resulted in the creation of datasets (life cycle inventories) that provide regionalized information on d-LUC in Brazil. Improvements include regionalized carbon stocks and d-LUC categories for pastures and forests.

Sustainable farming practices can be optimized by repurposing abandoned cultivated land and marginal lands. By integrating abandoned agricultural land and measuring specific biomass yields, these approaches can achieve optimal mitigation potential. According to (Gvein et al., 2023), utilizing land and prioritizing natural revegetation in areas of high biodiversity importance and remaining lands can lead to substantial improvements in greenhouse gas balance when evaluating options for CDR.

However, one of the critical limitations highlighted in the literature is the dependency of sustainability impacts on context-specific conditions, such as previous land use and biophysical characteristics. This variability can lead to trade-offs between GHG decreases and other sustainability purposes, making it essential to tailor approaches to local conditions. Other results highlight the potential of marginal lands and specific perennial crops to contribute to biomass production and CO₂ reduction. At the same time, they emphasize the need for further research and economic analysis to facilitate this transition (He et al., 2024).

The knowledge gap in this text lies in the uncertainty and variability surrounding the sustainability impacts of LUC, particularly regarding the estimation of GHG emissions and carbon sequestration. While methods like BRLUC 2.0 offer a framework for estimating LUC scenarios and emissions, they do not fully address the potential uncertainties or the complete impacts on emissions, especially across different regions. Furthermore, there is a need for more refined assessments when related to d-LUC and CO₂ emissions that are correlated with the stage of sugarcane cultivation, thus covering the role of planting driving habits and customs and the management of changes that have occurred in carbon stocks over time. More research is required to understand how varying conditions, such as previous land use and biophysical characteristics, influence GHG reduction outcomes and to improve the applicability of findings across diverse regions. A major limitation is the variability in sustainability impacts based on context-specific conditions, such as previous land use and biophysical characteristics. This inconsistency can lead to different outcomes in GHG reductions, making it challenging to generalize findings across different regions.

There is significant controversy surrounding the most suitable methods for estimating LUC and its associated emissions. The presence of indigenous carbon reserves and the time of planting due to agricultural expansion are decisive factors in the pattern of GHG emissions. The BRLUC 2.0 method, developed for Brazil, estimates 20-year LUC scenarios and CO₂ emission rates with grains, pastures and native forests in the country in each of the 27 states. To provide a framework for estimating LUC scenarios, the magnitude of uncertainty and its potential impact on total emissions remain inadequately addressed. It is based on temporal statistics and is in line with the most widely used standards to determine carbon footprints.

This approach can contribute positively to net carbon removal in the Brazilian agricultural sector, influencing both bioenergy and agricultural sustainability. In addition to reducing CO₂ emissions, biomass cultivation in degraded pasture areas can boost the recovery of such areas and promote environmental sustainability.

Research on the calculation of emissions caused by d-LUC associated with sugarcane cultivation has shown the importance of considering the effects of d-LUC associated with agriculture. This refined assessment of LUC and CO₂ emissions directly linked to the sugarcane planting phase includes the adoption of changes in appropriate driving habits and customs and soil carbon stocks over the last twenty years. (Guarenghi et al., 2023). To mitigate climate change, reducing GHG emissions in the agricultural sector includes planting biomass in degraded pasture areas, thereby increasing the production of sugarcane-derived biofuels, as well as LUC practices and driving habits and customs to increase carbon sequestration in the soil.

The goal of this study is to evaluate the use of regions with degraded pastures in Brazil to produce ethanol derived from sugarcane, while simultaneously evaluating the associated environmental and economic benefits. Specifically, the study focuses on assessing the economic advantages of CBIO as a tool for promoting CDR and natural revegetation, which contribute to climate change mitigation. Encourage the adoption of sustainable agricultural practices that align with environmental criteria for biomass cultivation, aiming to revitalize degraded areas while reducing greenhouse gas emissions.

The models adopted provide a variation in CO₂ emission rates from LUC according to different possibilities of land use transition, which can contribute with a great impact on the results (Novaes et al., 2017). The effort to avoid GHG emissions per hectare is greater thanks to the possibility of producing more biomass by adopting a new unused area, favoring the non-use of fossil fuels. The use of degraded pasture areas influences the carbon balance and can represent a significant advantage in LUC emissions. (2023) consider that increasing pastures for biofuels is an option that can be adopted to expand the areas necessary for sugarcane production, preventing an additional influence on the displacement of food crops or livestock. Sugarcane ethanol produced in integrated pasture scenarios has outperformed conventional systems. In this context, the National Biofuels Policy (Renovabio) is based on incentives to promote the valorization of Decarbonization Credits (CBIO) granted to biofuel producers according to the higher Environmental Energy Efficiency Scores (NEEA).

Decreased GHG emissions during the sugarcane planting phase favor the assessment of this stage and improve the NEEA. Therefore, there is a greater reduction in GHG for the equivalent quantity of ethanol produced. CBIOS to promote the valorization of degraded pasture areas instead of converting them into areas for cultivating perennial cereals can lead to significant environmental benefits.

The state of Mato Grosso was chosen for this study due to its rapid growth of biorefineries, which process both sugarcane and corn, as noted by (Moreira et al., 2020). We explore the potential of using degraded pasturelands in Brazil for biofuel production, particularly focusing on sugarcane. The datasets allow LUC to be incorporated into Brazilian agricultural products, at state, regional and national levels, showing a reduction in GHG emissions for soybeans and sugarcane. (Donke et al., 2020) identified improvements that had a significant impact. These include: (I) modeling LUC at the state level with official national data; (ii) regionalized carbon stock; (iii) inclusion of pasture and forest LUC categories; and (iv) considering sugarcane as a perennial crop. Minor changes in data sources and assumptions significantly impact emissions directly linked with LUCs in agricultural products. Furthermore, it also demonstrated the substantial impacts of the imprecisions associated with the LUC standard.

This study, based on the calculation of emissions caused by d-LUC associated with sugarcane cultivation, has shown the importance of considering the effects of d-LUC associated with agriculture and identifying and recommending driving habits and customs that can optimize biomass production while ensuring long-term sustainability and environmental benefits, addressing the gaps in current literature regarding effective strategies. This refined assessment of LUC and CO₂ emissions directly linked to the sugarcane planting phase includes changes in appropriate activities and land carbon stocks over the last twenty years (Guarenghi et al., 2023).

More specifically, it considers the economic advantages of increasing Decarbonization Credits (CBIOs) by measuring the positive balance of greenhouse gas emissions associated with carbon dioxide removal (CDR) and natural revegetation options.

The carbon balance in degraded areas can represent a significant advantage, acting as a tool for monitoring d-LUC emissions in relation to products, cultivation systems and natural vegetation preservation practices (Guarenghi et al., 2023). Studies indicate the need to conduct a comprehensive assessment of raw materials and biomass supply chains. The history of land use and raw material sourcing is more relevant than other specific conditions.

The transition from cultivating arable land to growing perennial energy crops leads to enhanced synergy, particularly regarding water use efficiency (Vera et al., 2022). There is a consensus on prioritizing the reduction of greenhouse gas emissions and revitalization of rural areas, particularly in the comprehensive evaluation of biomass raw materials (Mola-Yudego et al., 2024), confirming the significant potential for improvement for the entire agricultural system through LUC studies for biofuels highlight. According to (, 2015), under the right conditions, biofuels have the potential to significantly reduce the levels of GHG.

The method adopted enables Life Cycle Analysis (LCA) and Carbon Footprint (CFP) practitioners to easily incorporate d-LUC emissions for agricultural products at a regional, state and national level. According to (Donke et al., 2020) provides a more comprehensive representation of the diverse biome patterns in various parts of Brazil, while also recognizing sugarcane as a permanent crop.

The results obtained for the state of Mato Grosso with the use of degraded pasture areas to plant biomass for biofuels and the reduction of carbon in the soil resulted in environmental gains when considering LUC emissions, resulting in biofuel with greater efficiency in the GHG balance.

Regarding this specific case, ITAMARATI was able to reduce emissions from direct Land Use Change (d-LUC) by adopting degraded areas assuming an average gain of 19%. The positive results are associated with the d-LUC effect on the ethanol carbon footprint. As well as obtaining more sustainable biofuel and reducing GHG emissions, biomass cultivation in degraded areas allows for the recovery of pasture areas, increases carbon fixation in the soil and favors revegetation.

Despite the robustness of the approach as demonstrated by the BRLUC 2.0 method, which is in alignment with other methods at the global level [(Consultants, 2016); (B.S.I., 2012)], it is necessary to consider the uncertainty aspect, its magnitude and the potential impact on total emissions of agricultural products.

The impact of land use for specific agricultural production can result in trade-offs between GHG emission reductions depending on specific context conditions. Some authors, (Donke et al., 2020) and (Moreira et al., 2020), reinforce that sustainability impacts and, therefore, sustainability trade-offs of biomass planting are largely context-dependent (e.g., previous land use, type of raw material, biophysical conditions).

According to (Gvein et al., 2023), this cultivation option using degraded areas can achieve optimal mitigation potentials, however, it is very important to consider other regions and increase the number of measurements to reduce potential deviations in the results. Thinking of a global implication, mitigation using degraded or abandoned land can help minimize the risks associated with competition for land. However, the highest biomass yields are found in the tropical band, which is crucial for maximizing energy production.

The practices that increase carbon sequestration from the atmosphere can make a positive contribution to net carbon removal in the biofuels sector, according to (Cerri et al., 2022).

According to (Grangeia et al., 2022), the RenovaBio program was developed with the objective of incorporating market instruments to admit the capacity of each biofuel to reduce emissions: in the fuel matrix, this was designated national reduction parameters (defined for a period of 10 years) and certification of biofuel production, assigning different grades to each producer (higher grades will be given to the producer that produces a greater amount of net energy, with lower CO₂ emissions, in the life cycle).

The creation of CBIO, one of the instruments created, links these instruments. CBIO is an asset traded on the stock exchange, issued by the biofuel producer. With the creation of the regulated carbon market, questions arise about the CBIO trading market. The biggest of these is the definition of how the mechanisms for regulated carbon markets would be applied as proposed in Article 6 of the Paris Agreement (Grangeia et al., 2022).

Also, it is necessary to solve governance and institutional arrangement impasses to develop the framework to promote mitigation, projects and actions, on the necessary scale in Brazil.

The reduction of GHGs favors the valorization of CBIO by increasing the demand for renewable energy solutions with greater GHG reductions. As biorefineries produce biofuel with greater GHG balance efficiency, the value of certificates associated with carbon reduction increases. CBIOS can be utilized by producers with GHG reduction targets to mitigate their own emissions or to offer them to third parties in order to enhance their value. In comparison to gasoline, these practical strategies demonstrated substantial reductions in greenhouse gas emissions when assessed under the current representative conditions of the state of Mato Grosso, Brazil.

Importance of considering context-specific conditions in evaluating synergies and trade-offs and their relevance for sustainably developing appropriate policies and practices.

Options using degraded areas are crucial complements to the reduction of fossil fuel emissions, whose action can help phase out fossil fuels. The adoption of more sustainable practices with the adoption of environmental criteria for biomass cultivation can promote planting in degraded areas, favoring the valorization of CBIO and also boosting the recovery of these areas. And thus, encourage other farmers to produce bioethanol by adopting the same practices.

Notwithstanding, RenovaBio has increased the biofuels market, reducing fossil fuel emissions in the transport sector, in addition to being the first carbon pricing approach implemented in Brazil, these issues highlight the need for a deep understanding of the Program, as well as variants that directly correlate with this policy.

The abstract of this paper was presented at the Climate Change and Environmental Sustainability (CCES) Conference—4th Edition, which was held on the 2nd – 3rd of September 2024.