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Countries have pledged to different national and international environmental agreements, most prominently the climate change mitigation targets of the Paris Agreement. Accounting for carbon stocks and flows (fluxes) is essential for countries that have recently adopted the United Nations System of Environmental-Economic Accounting - ecosystem accounting framework (UNSEEA) as a global statistical standard. In this paper, we analyze how spatial carbon fluxes can be used in support of the UNSEEA carbon accounts in five case countries with available in-situ data. Using global multi-date biomass map products and other remotely sensed data, we mapped the 2010–2018 carbon fluxes in Brazil, the Netherlands, the Philippines, Sweden and the USA using National Forest Inventory (NFI) and local biomass maps from airborne LiDAR as reference data. We identified areas that are unsupported by the reference data within environmental feature space (6–47% of vegetated country area); cross-validated an ensemble machine learning (RMSE=9–39 Mg C ha - 1 and R 2 =0.16–0.71) used to map carbon fluxes with prediction intervals; and assessed spatially correlated residuals (<5 km) before aggregating carbon fluxes from 1-ha pixels to UNSEEA forest classes. The resulting carbon accounting tables revealed the net carbon sequestration in natural broadleaved forests. Both in plantations and in other woody vegetation ecosystems, emissions exceeded sequestration. Overall, our estimates align with FAO-Forest Resource Assessment and national studies with the largest deviations in Brazil and USA. These two countries used highly clustered reference data, where clustering caused uncertainty given the need to extrapolate to under-sampled areas. We finally provide recommendations to mitigate the effect of under-sampling and to better account for the uncertainties once carbon stocks and flows need to be aggregated in relatively smaller countries. These actions are timely given the global initiatives that aim to upscale UNSEEA carbon accounting. [ABSTRACT FROM AUTHOR]

Countries have pledged to different national and international environmental agreements, most prominently the climate change mitigation targets of the Paris Agreement. Accounting for carbon stocks and flows (fluxes) is essential for countries that have recently adopted the United Nations System of Environmental-Economic Accounting - ecosystem accounting framework (UNSEEA) as a global statistical standard. In this paper, we analyze how spatial carbon fluxes can be used in support of the UNSEEA carbon accounts in five case countries with available in-situ data. Using global multi-date biomass map products and other remotely sensed data, we mapped the 2010–2018 carbon fluxes in Brazil, the Netherlands, the Philippines, Sweden and the USA using National Forest Inventory (NFI) and local biomass maps from airborne LiDAR as reference data. We identified areas that are unsupported by the reference data within environmental feature space (6–47% of vegetated country area); cross-validated an ensemble machine learning (RMSE=9–39 Mg C ha - 1 and R 2 =0.16–0.71) used to map carbon fluxes with prediction intervals; and assessed spatially correlated residuals (<5 km) before aggregating carbon fluxes from 1-ha pixels to UNSEEA forest classes. The resulting carbon accounting tables revealed the net carbon sequestration in natural broadleaved forests. Both in plantations and in other woody vegetation ecosystems, emissions exceeded sequestration. Overall, our estimates align with FAO-Forest Resource Assessment and national studies with the largest deviations in Brazil and USA. These two countries used highly clustered reference data, where clustering caused uncertainty given the need to extrapolate to under-sampled areas. We finally provide recommendations to mitigate the effect of under-sampling and to better account for the uncertainties once carbon stocks and flows need to be aggregated in relatively smaller countries. These actions are timely given the global initiatives that aim to upscale UNSEEA carbon accounting. [ABSTRACT FROM AUTHOR]

In this study, projections and current status of municipal solid waste generation worldwide and its collection, final destination, and waste-to-energy technologies are reviewed. Firstly, an overview of waste generation worldwide is presented comparing income levels and the material composition of residues in several regions. This paper focused on contrasting Brazil and Portugal in terms of waste production and its management from generation to disposal or treatment. Furthermore, it is presented a summary of leading waste-to-energy technologies such as incineration, anaerobic digestion, gasification, pyrolysis, co-combustion, co-gasification, among others. Technical aspects of these thermo-chemical, biological, and physic-chemical processes for the production of biofuels such as biogas, syngas, biodiesel, and hydrogen-enriched gases are presented. Additionally, current aspects of the waste-to-energy market are exposed regarding the major players, investments, and expectations for the future of this activity with the elaboration of SWOT analyses. Finally, a review of greenhouse gases emissions worldwide is presented, specifically from Brazil and Portugal, as well as some consequences of these pollutant gases on the society and the environment and which are the main technologies for carbon dioxide capturing and sequestration as promising solutions for lower pollutant gases concentration in the atmosphere. This review paper aims to provide information for the management of municipal solid waste in Brazil and Portugal considering the mutual objective of meeting sustainable development goals. [ABSTRACT FROM AUTHOR]

Enhanced silicate rock weathering for long-term carbon dioxide sequestration has considerable potential, but depends on the availability of suitable rocks coupled with proximity to suitable locations for field application. In this paper, we investigate the established mining industry that extracts basaltic rocks for construction from the Paraná Basin, Sao Paulo State, Brazil. Through a Life Cycle Assessment, we determine the balance of carbon dioxide emissions involved in the use of this material, the relative contribution of soil carbonation and enhanced weathering, and the potential carbon dioxide removal of Sao Paulo agricultural land through enhanced weathering of basalt rock. Our results show that enhanced weathering and carbonation respectively emit around 75 and 135 kg carbon dioxide equivalent per tonne of carbon dioxide equivalent removed (considering a quarry to field distance of 65 km). We underline transportation as the principal process negatively affecting the practice and uncover a limiting road travel distance from the quarry to the field of 540 ± 65 km for carbonation and 990 ± 116 km for enhanced weathering, above which the emissions offset the potential capture. Regarding Sao Paulo State, the application of crushed basalt at 1 t/ha to all of the State's 12 million hectares of agricultural land could capture around 1.3 to 2.4 Mt carbon dioxide equivalent through carbonation and enhanced weathering, respectively. This study suggests a lower sequestration estimate than previous studies and emphasizes the need to consider all process stages through a Life Cycle Assessment methodology, to provide more reliable estimates of the sequestration potential of greenhouse gas removal technologies. • First assessment of the burdens associated with enhanced weathering and carbonation. • Transportation of the material greatly impacts the sequestration potential. • The quarry to field offsetting distance is 550 ± 65 km for carbonation. • On Sao Paulo average, the practice emit 0.110 kg CO 2 eq per kg of CO 2 removed. • The setup burdens of the practice reduce previous sequestration estimates. [ABSTRACT FROM AUTHOR]

Due to its low global share of direct energy consumption and greenhouse gas emissions (1–2%), the implications of technological transitions in the agricultural and forestry sector on the energy system have been overlooked. This paper introduces the Agriculture and Land Use Sector module part of the ModUlar energy System Environment (MUSE), a novel energy system simulation model. The study presents a generalisable method that enables energy modellers to characterise agricultural technologies within an energy system modelling framework. Different mechanisation processes were characterised to simulate intensification/extensification transitions in the sector and its wider implications in the energy and land use system aiming at providing reliable non-energy outputs similarly to those found in dedicated land use models. Additionally, a forest growth model has been integrated to explore the role of reforestation alongside decarbonisation measures in the energy system in achieving carbon mitigation pathways. To illustrate the model's capabilities, Brazil is used as case study. Outputs suggest that by 2030 under a 2 °C mitigation scenario, most of Brazil agricultural production would move from 'transitional' to 'modern' practices, improving productivity and reducing deforestation rates, at the expense of higher energy and fertiliser demand. By mid-century Brazil has the potential to liberate around 24.4 Mha of agricultural land, where large-scale reforestation could have the capacity to sequester around 5.6 GtCO 2 , alleviating mitigation efforts in the energy system, especially reducing carbon capture and storage technology investments in the industry and power sector. • A novel energy-oriented agriculture and land use systems model has been developed. • Mechanisation levels are characterised using cluster analysis and linear optimisation. • Role of reforestation alongside measures in the energy sector in Brazil are studied. • By 2050, modern mechanisation could represent 54–63% of agricultural production. • Brazil has the potential to sequester around 5.6 GtCO 2 through reforestation. [ABSTRACT FROM AUTHOR]

Stabilization at concentrations consistent with keeping global warming below 2 °C above the pre-industrial level will require drastic cuts in Greenhouse Gas (GHG) emissions during the first half of the century; net negative emissions approaching 2100 are required in the vast majority of current emission scenarios. For negative emissions, the focus has been on bioenergy with carbon capture and storage (BECCS), where carbon-neutral bioenergy would be combined with additional carbon capture thus yielding emissions lower than zero. Different BECCS technologies are considered around the world and one option that deserves special attention applies CCS to ethanol production. It is currently possible to eliminate 27.7 million tonnes (Mt) of CO 2 emissions per year through capture and storage of CO 2 released during fermentation, which is part of sugar cane-based ethanol production in Brazil. Thus, BECCS could reduce the country’s emissions from energy production by roughly 5%. Such emissions are additional to those due to the substitution of biomass-based electricity for fossil-fueled power plants. This paper assesses the potential and cost effectiveness of negative emissions in the joint production system of ethanol and electricity based on sugar cane, bagasse, and other residues in Brazil. An important benefit is that CO 2 can be captured twice along the proposed BECCS supply chain (once during fermentation and once during electricity generation). This study only considers BECCS from fermentation because capturing such CO 2 is straightforward, thus potentially representing a cost-effective mitigation option for Brazil compared to other alternatives. The assessment shows that fuel prices would increase by less than 3.5% due to the adoption of BECCS from fermentation, while increasing investors’ revenues are sufficient to compensate for the investment required. With appropriate government subsidies, or by sharing BECCS costs between all car fuels and all electricity supplied by hydro and bioelectricity, the increment in ethanol and electricity prices could be less than 1% for the final consumer. Meanwhile it would supply 77.3% of all cars’ fuel (private cars) and 17.9% of all electricity in Brazil. [ABSTRACT FROM AUTHOR]

Soil and climatic conditions allied to advanced forestry technologies have enabled the development of planted forests in some regions of Brazil with some of the highest productivity rates in the world. However, the intense use of agricultural inputs and mechanization of production and wood transportation imply significant environmental impacts, such as the emission of carbon and nitrogen compounds. The purpose of this paper is to compare a model of an Integrated Crop-Livestock-Forestry System with more conventional eucalyptus forestry using a Cleaner Production approach to demonstrate the economic and environmental advantages of such a system. This is based on an environmental, energy, and economic analysis integrating Life Cycle Assessment and Cleaner Production approaches. Life Cycle Inventories consist of primary data obtained from the states of Bahia, Espírito Santo and Minas Gerais in Brazil, in partnership with Forestry Producers and a Forestry Company, which is the largest producer of hardwood pulp in the world. The inventories of conventional short-cycle eucalyptus production systems to supply the Forestry Company were quantified from seedling preparation to harvesting operations. The following production systems were evaluated: Reference system – Planting + Replanting (S1); Planting + Regrowth (S2), and Crop-Livestock-Forestry (S3). The adoption of CP measures in S3 reduced the use of inputs by 35% and increased gross revenue compared to S1. The processes that most contributed to the impact categories analyzed were soil preparation, emissions of inputs used in the field, and mechanized harvesting. However, biogenic carbon sequestration included −783 kg CO 2 eq/m3 of wood for S1. The S2 system had lower impacts compared to S1. Integrated Crop-Livestock-Forestry System - S3 showed a better environmental performance for most of the impact categories analyzed and presented a better financial return compared with S1 and S2. The implementation of the CP measures in S3 provides an immediate payback. Based on the conditions of this study, the CP strategy for silviculture is an economically viable option to increase the net CO 2 sequestration of forest production. This research intends to promote the study of eucalyptus forest production under tropical conditions, using the combined use of LCA and CP approach presented in this study from primary data. The CP and LCA integration provided methodological advances and more detailed information on the environmental performance of short-cycle eucalyptus production by identifying operational practices for the analyzed systems yielding environmental and financial gains. CP proved to be effective in providing information for decision-making at the process level without losing the broader view of the environmental performance of the analyzed product systems. [ABSTRACT FROM AUTHOR]

Soil and climatic conditions allied to advanced forestry technologies have enabled the development of planted forests in some regions of Brazil with some of the highest productivity rates in the world. However, the intense use of agricultural inputs and mechanization of production and wood transportation imply significant environmental impacts, such as the emission of carbon and nitrogen compounds. The purpose of this paper is to compare a model of an Integrated Crop-Livestock-Forestry System with more conventional eucalyptus forestry using a Cleaner Production approach to demonstrate the economic and environmental advantages of such a system. This is based on an environmental, energy, and economic analysis integrating Life Cycle Assessment and Cleaner Production approaches. Life Cycle Inventories consist of primary data obtained from the states of Bahia, Espírito Santo and Minas Gerais in Brazil, in partnership with Forestry Producers and a Forestry Company, which is the largest producer of hardwood pulp in the world. The inventories of conventional short-cycle eucalyptus production systems to supply the Forestry Company were quantified from seedling preparation to harvesting operations. The following production systems were evaluated: Reference system – Planting + Replanting (S1); Planting + Regrowth (S2), and Crop-Livestock-Forestry (S3). The adoption of CP measures in S3 reduced the use of inputs by 35% and increased gross revenue compared to S1. The processes that most contributed to the impact categories analyzed were soil preparation, emissions of inputs used in the field, and mechanized harvesting. However, biogenic carbon sequestration included −783 kg CO 2 eq/m3 of wood for S1. The S2 system had lower impacts compared to S1. Integrated Crop-Livestock-Forestry System - S3 showed a better environmental performance for most of the impact categories analyzed and presented a better financial return compared with S1 and S2. The implementation of the CP measures in S3 provides an immediate payback. Based on the conditions of this study, the CP strategy for silviculture is an economically viable option to increase the net CO 2 sequestration of forest production. This research intends to promote the study of eucalyptus forest production under tropical conditions, using the combined use of LCA and CP approach presented in this study from primary data. The CP and LCA integration provided methodological advances and more detailed information on the environmental performance of short-cycle eucalyptus production by identifying operational practices for the analyzed systems yielding environmental and financial gains. CP proved to be effective in providing information for decision-making at the process level without losing the broader view of the environmental performance of the analyzed product systems. [ABSTRACT FROM AUTHOR]

Brazil is one of the largest producers of eucalyptus that is used for manufacturing pulp and paper; this contributes directly to the issue of carbon emissions. Reforestation of eucalyptus appears as a viable alternative for mitigating these carbon emissions, leveraging their high productivity to that of other leading countries in the market, such as Finland and Sweden. This study aims to develop a model for monitoring and evaluating forest growth and quantifying wood stocks and sequestered carbon. System dynamics was used to simulate forest growth. Forest growth was modeled from eight regions with dissimilar edaphoclimatic characteristics, in the state of Minas Gerais, in Brazil. The model was sensitive enough to the characteristics of the regions, where the difference in forest stocks was 45.1% at the end of 30 years in a harvest cycle of 7 years. It was found that the typical harvest cycle in practice by leading companies did not always yield a higher sequestered CO 2 accumulated stock. By shortening the harvest cycle, it was possible to obtain a gain of up to 21.0% in the sequestered CO 2 stock. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews current knowledge on changes in carbon stocks upon land use conversion in the Brazilian Cerrado. First, we briefly characterize the savanna ecosystem and summarize the main published data on C stocks under natural conditions. The effects of increased land use pressure in the Cerrado and current uncertainties of estimations of changes in land cover and land use are reviewed next. Thereafter, we focus on soil organic carbon (SOC) dynamics due to changes in land use, particularly conversion to pastures and soybean-based cropping systems, and effects of management practices such as soil fertilization, crop rotations and tillage practices. Most studies considered here suggest that more intensive agriculture, which include no-till practices and the implementation of best or recommended management practices (RMP), reduces SOC losses after land use conversion from conventional tillage-based, monocropping systems; however, these studies focussed on the first 0.3m of soil, or less, and seldom considered full carbon accounting. To better estimate possible global warming mitigation with agriculture in the Cerrado more comprehensive studies are needed that analyse fluxes of the biogenic greenhouse gases (GHG; CO2, N2O and CH4) to determine the net global warming potential (GWP). Follow up studies should include the application of an integrated modelling system, comprised of a Geographic Information System (GIS) linked to dynamic modelling tools, to analyse SOC dynamics and make projections for possible changes in net C flows in the Cerrado region upon defined changes in soil use and management. [Copyright &y& Elsevier]

The present paper reports the assessment of the vegetation occupancy rate of the roadside, through analysis of aerial photographs. Using such value the potential of these areas to be employed as carbon (C) sinks was also assessed. Moreover, for the areas suitable for afforestation, the potential for carbon sequestration was estimated considering different species of vegetation, both native (scenario 1) and exotic (formed by Pinus sp. and Eucalyptus sp. - scenario 2). The study was carried out through GIS techniques and two regions were considered. A set of equations was used to estimate the rate of occupancy over the study areas, as well as amounts of fixed C under the above scenarios. The average occupancy rate was 0.06%. The simulation showed a higher potential for C sequestration in scenario 2, being the estimated amounts of CO2 sequestered from the atmosphere per km of roadside: 131 tons of CO2 km-1 of highway to native species and 655 tons of CO2 km-1 of highway for exotic species (over period of 10 years for both estimates). If we consider the whole road network of the São Paulo State (approximately 190 000 km) and that a considerable part of this road work is suitable to receive this kind of service, it is possible to predict the very high potential for C sequestration if managers and planners consider roadside as area for afforestation. [ABSTRACT FROM AUTHOR]

This article describes a new concept to reduce carbon dioxide emissions of offshore oil production of high gas-to-oil ratio reservoirs and high content of CO2, denominated Offshore Salt Cavern Ultra-deep Water CCS (Carbon Capture and Storage) System. This hybrid system is intended for natural gas storage, the gravitational separation between CO 2 /CH 4 , and CO 2 confinement for final destination. This development emerged from a current demand of some Brazilian pre-salt reservoirs to destinate a gas stream with high CO 2 contamination, produced during the oil extraction. These reservoirs have a continuous salt rock layer of 2000 m as caprock making the construction possible of salt caverns by leaching using seawater. In the first stage of technology development, the system will only store a gas stream contaminated with a high concentration of CO 2. In the second stage of its development, it will allow not only the separation of natural gas from the CO 2 but also its storage and the monetization of CH 4. This paper presents the conceptual design of this technology, showing the steps from the parametric study to select the best relation between flowrate, leaching time, structural stability, and the volume of gas with the high content of CO 2 storage, up to the final geomechanical design using the set of parameters selected. [ABSTRACT FROM AUTHOR]