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Brazil is recognized for possessing a low carbon-intensive energy matrix, with most of its power being generated from hydroelectricity. Its greenhouse gas emissions profile is dominated by deforestation and land-use change. Despite this characteristic, the country has been committed to the development of carbon capture and geological storage (CCS) research since this technology started to be recognized as a relevant solution for greenhouse gas emission reductions. This development has gained attention recently owing to the beginning of the production of pre-salt reservoirs, which may contain significant amounts of CO2 in the produced fluids. The work has been carried out mostly through the efforts of the academia and industrial enterprises. This paper presents a summary and a brief description of the recent activities being carried out by these sectors, aiming to develop and promote CCS in Brazil. [ABSTRACT FROM AUTHOR]

Bioenergy could play a major role in decarbonizing energy systems in the context of the Paris Agreement. Large‐scale bioenergy deployment could be related to sustainability issues and requires major infrastructure investments. It, therefore, needs to be studied carefully. The Bioenergy and Land Optimization Spatially Explicit Model (BLOEM) presented here allows for assessing different bioenergy pathways while encompassing various dimensions that influence their optimal deployment. In this study, BLOEM was applied to the Brazilian context by coupling it with the Brazilian Land Use and Energy Systems (BLUES) model. This allowed investigating the most cost‐effective ways of attending future bioenergy supply projections and studying the role of recovered degraded pasture lands in improving land availability in a sustainable and competitive manner. The results show optimizing for limiting deforestation and minimizing logistics costs results in different outcomes. It also indicates that recovering degraded pasture lands is attractive from both logistics and climate perspectives. The systemic approach of BLOEM provides spatial results, highlighting the trade‐offs between crop allocation, land use and the logistics dynamics between production, conversion, and demand, providing valuable insights for regional and national climate policy design. This makes it a useful tool for mapping sustainable bioenergy value chain pathways. [ABSTRACT FROM AUTHOR]

Mangroves have among the highest carbon densities of any tropical forest. These 'blue carbon' ecosystems can store large amounts of carbon for long periods, and their protection reduces greenhouse gas emissions and supports climate change mitigation. Incorporating mangroves into Nationally Determined Contributions to the Paris Agreement and their valuation on carbon markets requires predicting how the management of different land‐uses can prevent future greenhouse gas emissions and increase CO2 sequestration. We integrated comprehensive global datasets for carbon stocks, mangrove distribution, deforestation rates, and land‐use change drivers into a predictive model of mangrove carbon emissions. We project emissions and foregone soil carbon sequestration potential under 'business as usual' rates of mangrove loss. Emissions from mangrove loss could reach 2391 Tg CO2 eq by the end of the century, or 3392 Tg CO2 eq when considering foregone soil carbon sequestration. The highest emissions were predicted in southeast and south Asia (West Coral Triangle, Sunda Shelf, and the Bay of Bengal) due to conversion to aquaculture or agriculture, followed by the Caribbean (Tropical Northwest Atlantic) due to clearing and erosion, and the Andaman coast (West Myanmar) and north Brazil due to erosion. Together, these six regions accounted for 90% of the total potential CO2 eq future emissions. Mangrove loss has been slowing, and global emissions could be more than halved if reduced loss rates remain in the future. Notably, the location of global emission hotspots was consistent with every dataset used to calculate deforestation rates or with alternative assumptions about carbon storage and emissions. Our results indicate the regions in need of policy actions to address emissions arising from mangrove loss and the drivers that could be managed to prevent them. [ABSTRACT FROM AUTHOR]

Cement production contributes 8–9% of all anthropogenic CO2 emissions worldwide, and further increases in the future are expected. Traditional solutions for reducing emissions, including energy efficiency, using alternative fuels, and clinker‐to‐cement ratio reduction, are insufficient to ensure the necessary mitigation. Based on the concept of material efficiency, this study identifies new alternatives for reducing CO2 emissions by adopting a set of technological solutions to increase the industrialization of cement‐based products and the use of fillers considering a cradle‐to‐use approach. Besides, increasing the filler content in mortars and plain concrete is a desirable strategy, because it increases the carbonation rate, accelerating the CO2 sequestration from the atmosphere. Based on data from the Brazilian cement industry technology roadmap, this study quantitatively evaluates, up to 2050, the CO2 mitigation potential and the reduction of cement consumption for each adopted technological solution. The marginal abatement costs are also included to quantify each considered solution's cost‐effectiveness and compared with alternatives like carbon capture and storage. The results show that increasing the cement use efficiency enables CO2 emissions reduction by up to 45% by 2050, with a cost of USD –1.36 for each avoided metric ton of CO2, while accelerating the mortar carbonation rate. This article met the requirements for a gold–gold JIE data openness badge described in http://jie.click/badges. [ABSTRACT FROM AUTHOR]

The adoption of no‐till (NT) has been proposed to recover soil organic carbon (SOC), which will aid the mitigation of climate change. However, studies have questioned the potential of NT soils to deliver SOC sequestration and sustain crop yields. No‐till experiments are relatively recent (<50 years) and very few studies were able to assess SOC dynamics in high‐yield agroecosystems. We used the DSSAT‐CENTURY model to predict long‐term SOC (0–30 cm) using datasets from two experiments assessing tillage and nitrogen (N) sources in a Mollisol from the midwest United States (28 years) and tillage and crop rotations in an Oxisol from southern Brazil (33 years). The conversion of prairie and grassland soils to conventional agriculture decreased SOC by 61 and 12% in the Mollisol and Oxisol, respectively. Soil organic C accrual in NT soils was >0.5 Mg C ha−1 year−1 under medium‐low‐yield maize in the Mollisol and negligible in the Oxisol under soybean/wheat rotation. Organic fertilization and crop rotation increased SOC accrual at both sites. Simulated SOC had good agreement with observations for NT soils but overestimated SOC in tilled soils. The model's parameters were then modified for tilled soils. Long‐term simulations (100 years) revealed that SOC accrual in NT soils (0–15 cm) is partially offset by losses at 15–30 cm under low C inputs. Simulations with best crop management practices (BP; irrigation, high‐yield cultivars, higher plant density and improved N fertilization) augmented C inputs and SOC stocks, ultimately recovering SOC to the levels of prairie soils. Our results suggest that the adoption of NT, recycling of organic fertilizers and the use of BP should be further promoted for recovery and permanence of SOC in agricultural soils. Highlights: Studies have questioned the potential of conservation agriculture (CA) to deliver SOC sequestration and sustain crop yields.We used the DSSAT‐CENTURY model to simulate SOC dynamics in temperate and subtropical soils.No‐till under moderate C/N inputs recovered topsoil SOC, but subsurface losses offset SOC accrual.Use of CA, organic amendments and best practice crop management (BP) is crucial for long‐term SOC storage and permanence. [ABSTRACT FROM AUTHOR]

Biomass is responsible for 25% of the primary energy supply in Brazil. However, future biomass demand will be influenced by many factors. This study evaluates potential pathways for the utilization of biomass in Brazil until 2050, while considering novel biobased sectors (renewable jet fuel and biochemicals), resource competition, and greenhouse gas (GHG) emissions. Whereas other least‐cost optimization models assess biobased options to meet energy and chemicals demand in Brazil to a limited extent, this study provides a detailed breakdown of biomass feedstock, including an extensive portfolio of biomass conversion technologies. A least‐cost optimization model is used to assess the demand for energy and chemicals, and the competition between biomass and other climate‐mitigation measures such as renewable power generation technologies, carbon capture and storage (CCS), and energy efficiency. Varied over the three scenarios, 86–96% of the sustainable biomass supply potential is used. Under more stringent mitigation targets, novel biomass conversion technologies start to play an important role: Biobased electricity production with CCS, jet fuel production from lignocellulosic biomass, and chemicals are partly produced from ethanol and bio‐naphtha. The modeling framework provides a transparent view of which type of biomass can be used for which specific purpose. It is therefore an interesting tool for future research, for example to examine the dynamic interaction with demand for land. © 2019 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article discusses research on the conversion of Brazilian Atlantic Forest and provision of ecosystem services in the area. The study by E. H. Ditt el al evaluated the benefits and costs of land use patterns and quantified ecosystem services from different land use in the Atibainha Reservoir to determine the impact of land use changes considering four ecosystem services including carbon sequestration and purification of water. Findings indicated that the most important services that native forest can provide include carbon sequestration.

Conservation agriculture can provide a low-cost competitive option to mitigate global warming with reduction or elimination of soil tillage and increase soil organic carbon (SOC). Most studies have evaluated the impact of zero till (ZT) only on surface soil layers (down to 30 cm), and few studies have been performed on the potential for C accumulation in deeper layers (0–100 cm) of tropical and subtropical soils. In order to determine whether the change from conventional tillage (CT) to ZT has induced a net gain in SOC, three long-term experiments (15–26 years) on free-draining Ferralsols in the subtropical region of South Brazil were sampled and the SOC stocks to 30 and 100 cm calculated on an equivalent soil mass basis. In rotations containing intercropped or cover-crop legumes, there were significant accumulations of SOC in ZT soils varying from 5 to 8 Mg ha−1 in comparison with CT management, equivalent to annual soil C accumulation rates of between 0.04 and 0.88 Mg ha−1. However, the potential for soil C accumulation was considerably increased (varying from 0.48 to 1.53 Mg ha−1 yr−1) when considering the soil profile down to 100 cm depth. On average the estimate of soil C accumulation to 100 cm depth was 59% greater than that for soil C accumulated to 30 cm. These findings suggest that increasing sampling depth from 30 cm (as presently recommended by the IPCC) to 100 cm, may increase substantially the estimates of potential CO2 mitigation induced by the change from CT to ZT on the free-draining Ferralsols of the tropics and subtropics. It was evident that that legumes which contributed a net input of biologically fixed N played an important role in promoting soil C accumulation in these soils under ZT, perhaps due to a slow-release of N from decaying surface residues/roots which favored maize root growth. [ABSTRACT FROM AUTHOR]