Search Results (440)

Manure is a valuable organic resource for sustainable agriculture, enhancing soil fertility and promoting nutrient cycling; however, it also contributes significantly to methane and nitrous oxide emissions. The European Green Deal and Latvia’s National Energy and Climate Plan have set targets for reducing agricultural greenhouse gas (GHG) emissions, including those related to improved manure management. Therefore, this research aims to estimate the future manure production in Latvia to determine the potential for reducing GHG emissions by 2050. Using the LASAM model developed in Latvia, the number of farm animals, the amount of manure, and the associated GHG emissions were projected for the period up to 2050. The calculations followed the Intergovernmental Panel on Climate Change (IPCC) methodology and were based on national indicators and current national GHG inventory data covering the period of 2021–2050. Significant changes in the structure of manure in Latvia are predicted by 2050, with the proportion of liquid manure expected to increase while the amounts of solid manure and manure deposited by grazing animals are expected to decrease. The GHG emission projection results indicate that by 2050, total emissions from manure management will decrease by approximately 5%, primarily due to a decline in the number of farm animals and, consequently, a reduction in the amount of manure. In contrast, methane emissions are expected to increase by approximately 5% due to production intensification. The research results emphasise the need to introduce more effective methane emission reduction technologies and improved projection approaches. Full article

Sustainable aviation fuel (SAF) is a drop-in alternative to conventional jet fuels, designed to reduce greenhouse gas (GHG) emissions while requiring minimal infrastructure changes and certification under the American Society for Testing and Materials (ASTM) D7566 standard. This study assesses recently identified high-energy-density (HED) strained polycycloalkanes as SAF candidates. Strain energy (E_se) was calculated using density functional theory (DFT), while operational properties such as boiling point (BP) and flash point (FP) were predicted using support vector regression (SVR) models. The models demonstrated strong predictive performance (R² > 0.96) with mean absolute errors of 6.92 K for BP and 9.58 K for FP, with robustness sensitivity analysis. It is found that approximately 65% of these studied polycycloalkanes fall within the Jet A fuel property boundaries. The polycycloalkanes (C₉–C₁₅) with strain energies below approximately 60 kcal/mol achieve an balance between energy density and ignition safety, aligning with the specifications of Jet A. The majority of structures were dominated by five-membered rings, with a few three- or four-membered rings enhancing favorable trade-offs among BP, FP, and HED. This early pre-screening indicates that moderately strained polycycloalkanes are safe, energy-dense candidates for next-generation sustainable jet fuels and provide a framework for designing high-performance SAFs. Full article

Fruit production is a high environmental impact sector, requiring sustainable strategies that reduce greenhouse gas (GHG) emissions, improve resource efficiency, and maintain fruit quality. This study assessed the environmental performance of innovative substrates with biodegradable additives and organic binders in tunnel-grown raspberry production. The functional unit was 1 kg of marketable fruit, and the experiment was conducted in Karwia, Poland. GHG emissions were calculated for eight substrate variants following ISO 14040 and 14041 guidelines. The baseline was coconut fiber, while modified variants included the additions of sunflower husk biochar and/or a wood-industry isolate, representing sustainable strategies in soilless cultivation. Emissions ranged from 0.728 to 1.226 kg CO₂ eq/kg of raspberries, with the control showing the highest values. All modified substrates (produced based on a mixture of biochar and isolate) reduced emissions, with the most efficient variant achieving nearly a 40% decrease. Water use efficiency was decisive, as consumption declined from 2744 m³/ha (control) to 1838 m³/ha in improved variants. Substrate air–water properties proved critical for both environmental and economic outcomes. The findings confirm that substrate modification constitutes an effective, sustainable strategy for raspberry production under high tunnels, supporting climate-smart horticulture and resource-efficient food systems. Full article

The construction sector accounts for one-third of Europe’s total greenhouse gas (GHG) emissions, offering significant potential for emission reduction. Emission reduction can be achieved by substituting conventional building materials with wood- or bio-based alternatives; the difference in GHG emissions is referred to as the substitution potential (SP). In this study, a literature review was conducted to identify studies in which SPs had been determined. The calculation methods used for these SPs were then analysed in detail. The analysis considered the general conditions, outcomes, and scaling effects, revealing that differing initial conditions lead to inconsistent results. Therefore, transparent allocation of SPs and comparable product life cycle assessments (LCAs) based on functional equivalence are essential. To reliably extrapolate the benefits of wood use to the entire construction sector, scaling effects must be justified by consistent functional equivalence. For policy relevance, it is crucial that SPs are determined using the standardised rules and that the building level, as the actual place of material use, is not overlooked. This is particularly important when scaling up the effects of increased wood use to the landscape level. Only with these measures SPs at the product level can provide reliable results in a broader context. Additionally, the studies reviewed indicate that changes in forest management have not yet been considered. Full article

Brazil is a leading producer of multi-purpose crops—such as corn, soybean, and sugarcane—used for human consumption, animal feed, and biofuel production. This study generated agricultural inventories for these three crops based on state-level information. For sugarcane, we used primary data submitted by ethanol producers to RenovaBio. For soybean and corn, we retrieved and updated data from a previous study, which gathered information through panel consultations with farmers and sector experts. We also calculated the greenhouse gas (GHG) emissions associated with the crops using the Life Cycle Assessment (LCA) method. Our analysis revealed significant variability in emissions across states, especially for corn and sugarcane. Without considering direct land use change (dLUC), the states with the highest and lowest emissions for each crop were as follows: (i) sugarcane: Paraíba at 54 and Goiás at 37, with a national average of 42 kg CO₂e/t cane; (ii) soybean: Maranhão at 344 and Minas Gerais at 300, average of 323 kg CO₂e/t soy; (iii) first-crop corn: Maranhão at 416 and Mato Grosso at 264, average of 300 kg CO₂e/t corn; (iv) second-crop corn: Paraná at 306 and Minas Gerais at 153, average of 255 kg CO₂e/t corn. Emissions were inversely related to crop yields, with the exception of second-crop corn. In general, lower yields were observed in states of the Northeast region (e.g., Maranhão and Paraíba), which face challenges due to irregular climate patterns and water deficits. For sugarcane cultivated in the same region, emissions from straw burning had a significant impact, with the practice being applied to more than 60% of the crop area. If dLUC emissions were included, variability would increase dramatically—particularly for corn and soybean in some states—due to patterns of cropland expansion into native vegetation areas over the 2000–2019 period. In particular, total soybean emissions would range from 471 in Paraná to 2173 in Maranhão, with a national average of 1022 kg CO₂e/t soy. These findings can be valuable as references for life cycle databases, for the development of state-specific emission factors for biofuels produced from the investigated crops, and as supporting information for decarbonization programs. Full article

The deployment of Sustainable Aviation Fuels (SAFs) is central to decarbonizing aviation. However, diverse regulatory frameworks create complexity for SAF market deployment. Differing greenhouse gas (GHG)-reduction thresholds, feedstock eligibility rules and certification systems increase the compliance burden, especially for those operating across regional and international markets. This paper compares an example of regional approach (European) with the international ICAO sustainability certification. The comparison focuses on chain-of-custody models, substantiality principles, GHG accounting methodologies and approaches to ILUC. It highlights the need for harmonized GHG calculation rules, mutual recognition of certification schemes and interoperable traceability systems. Aligning these elements is critical for reducing administrative barriers, supporting market integration and enabling scalable SAF deployment. The analysis aims to assist policymakers, certifiers and producers in developing coordinated and transparent regulatory strategies. Full article

To mitigate climate change, achieving net-zero carbon dioxide (CO₂) emissions across all sectors is essential. In the floricultural and landscaping industries, a key concern is whether the production and use of landscape plants contribute to CO₂ reduction. However, few studies have assessed the greenhouse gas (GHG) budgets of landscape plant production. This study quantified all major components of GHG budgets to determine whether herbaceous plant production acts as a GHG sink or source. Kentucky bluegrass sod and three herbaceous plants (Hedera canariensis, Liriope muscari, and Tagetes patula) were investigated for their GHG (CO₂, CH₄, and N₂O) budgets. For Kentucky bluegrass sod production, the total GHG budget was calculated as −17.764 t-CO₂e ha⁻¹ year⁻¹, comprising carbon sequestration (23.014 t-CO₂/ha), GHG fluxes (0.049 t-CO₂e/ha), and GHG emissions from energy and resource consumption (5.201 t-CO₂e/ha). These results indicate that Kentucky bluegrass sod production functions as a GHG sink. In contrast, the total GHG budgets for potting production of the three herbaceous plants were positive, primarily due to higher GHG emissions from the use of potting soil and granular pesticides. To reduce net CO₂ emissions in herbaceous plant production, using biochar as a growth medium and minimizing granular pesticides is an effective approach. Full article

Abalone is among the most highly prized seafoods, valued for its delicate flavor and texture. As abalone aquaculture continues to expand, addressing its environmental impacts has become increasingly important. Although aquaculture is recognized as a contributor to greenhouse gas (GHG) emissions, the specific mechanisms and pathways of GHG emissions—particularly in abalone farming—remain poorly understood. To clarify the patterns and drivers of GHG emissions in abalone (Haliotis discus) culture systems, this study was conducted in three aquaculture ponds located in Gongliao District, New Taipei City, Taiwan. We measured CO₂, CH₄, and N₂O fluxes along with key environmental parameters to assess variation across sampling locations, times, and seasons. The results showed that sampling time had no significant effect on GHG flux variations, whereas seasonal changes influenced all three gases, and sampling location significantly affected N₂O flux only. During the culture period, average fluxes were 2.19 ± 10.83 mmol m⁻² day⁻¹ for CO₂, 2.11 ± 2.81 µmol m⁻² day⁻¹ for CH₄, and 1.65 ± 2.73 µmol m⁻² day⁻¹ for N₂O, indicating that the abalone ponds served as net sources of these GHGs. When converted to CO₂-equivalents (CO₂-eq), the total average CO₂-eq flux from the ponds was 0.02 ± 0.09 mg CO₂-eq m⁻² day⁻¹, calculated using global warming potential (GWP₂₀ and GWP₁₀₀) metrics. This study provides the first comprehensive assessment of GHG emissions in abalone pond systems and offers valuable insights into their emission dynamics. The findings contribute to the scientific basis needed to improve aquaculture GHG inventories. Full article

Over 15 billion tonnes year⁻¹ of biomass is used globally, yet 14% is downcycled for energy, forfeiting billions in potential revenue for higher-value products. Robust metrics that couple cascading use with cradle-to-gate greenhouse gas (GHG) emissions and economic value are essential for identifying superior biomass pathways. The aim of this review is to systematically map biomass utilization indicators published between 2010 and 2025; compare their treatment regarding circularity, climate, and economic value; and introduce the enhanced Bioresource Utilization Index (eBUI). A PRISMA-aligned search of Scopus and Web of Science yielded 80,808 records, of which 33 met the eligibility criteria. Each indicator was scored on cascading, data intensity, and environmental and economic integration, as well as computational complexity and sector scope. The Material Circularity Indicator, Biomass Utilization Efficiency, the Biomass Utilization Factor, and legacy BUI satisfied no more than two criteria simultaneously, and none directly linked mass flows to both GHG emissions and net revenue. The eBUI concept integrates mass balance, lifecycle carbon intensity, and value coefficients into a single 0–1 score. An open-access calculator and data quality checklist accompany the metric, enabling policymakers and industry to prioritize biomass pathways that are circular, climate-smart, and economically attractive. Full article

Environmental emissions from the maritime sector, including CO₂, NO_x, and SO_x, contribute significantly to global air pollution and climate change. The International Maritime Organization (IMO) has set a target to reduce greenhouse gas emissions from international shipping to reach zero GHG by 2050 compared to 2008 levels. To meet these goals, the IMO strongly encourages the transition to alternative fuels, such as hydrogen, ammonia, and biofuels, as part of a broader decarbonization strategy. This study presents a comparative analysis of converting conventional diesel engines to dual-fuel systems utilizing alternative fuels such as methanol or natural gas. The methodology of this research is based on theoretical calculations to estimate various types of emissions produced by conventional marine fuels. These results are then compared with the emissions generated when using methanol and natural gas in dual-fuel engines. The analysis is conducted using the EVER ALOT container ship as a case study. The evaluation focuses on both environmental and economic aspects of engines operating in natural gas–diesel and methanol–diesel dual-fuel modes. The results show that using 89% natural gas in a dual fuel engine reduces nitrogen oxides (NO_x), sulfur oxides (SO_x), carbon dioxide (CO₂), particulate matter (PM), and carbon monoxide (CO) pollutions by 77.69%, 89.00%, 18.17%, 89.00%, and 30.51%, respectively, while the emissions percentage will be 77.78%, 91.00%, 54.67%, 91.00%, and 55.90%, in order, when using methanol as a dual fuel with percentage 91.00% Methanol. This study is significant as it highlights the potential of natural gas and methanol as viable alternative fuels for reducing harmful emissions in the maritime sector. The shift toward these cleaner fuels could play a crucial role in supporting the maritime industry’s transition to low-emission operations, aligning with global environmental regulations and sustainability goals. Full article

Additive manufacturing (AM) is an Industry 4.0 technology that assists or replaces the conventional manufacturing (CM) of complex geometries in various sectors, including transport, steel, aerospace, military, and architecture. The aim is to improve processes, reduce energy consumption, atmospheric emissions, and solid waste, and streamline stages while complying with the new environmental regulations. The main objective of this work was to carry out a cradle-to-gate Life Cycle Assessment (LCA), considering the raw material extraction, pre-processing, manufacturing, and post-processing stages, comparing two manufacturing methods for the same ER-90 metal flange part, conventional forging and wire and arc additive manufacturing (WAAM), all following the requirements and operations proposed by the ISO 14040/44 standard. WAAM is a Directed Energy Deposition (DED) technology that uses welding techniques to produce 3D objects with more complex geometries. Compared to the forging industry, which requires a lot of heat and kinetic energy in its metal part production stages, WAAM is a more sustainable and modern alternative because it does not require high temperatures and energy to produce the same parts. The environmental indicators compared in the process stages were energy consumption, greenhouse gas (GHG) emissions, and solid waste. The total energy consumption in AM was 18,846.61 MJ, the GHG emissions were 864.49 kgCO₂-eq, and the solid waste generated was 142.34 kg, which were 63.8 %, 90.5%, and 31.6% lower than the environmental indicators calculated for CM, respectively. Full article

Different crop production scenarios and crop rotation systems should be investigated with lower greenhouse gas (GHG) intensity levels, with it being possible to reach net-zero GHG emissions from grain production farms. This study was divided into three stages—the development of spreadsheets for data acquisition for each crop rotation, calculations of GHG emissions based on IPCC methodologies and specific regional emission factors, and an analysis of the main emissions and sinks sources we evaluated, including the potential for soil and biomass carbon (C) sequestration to offset agricultural emissions. The system C footprints were 2413, 2209, and 2096 kg CO₂eq ha⁻¹ for farms K, M, and G, respectively, demanding estimated C sequestration (soil or biomass) rates of 657, 602, and 571 kg C ha⁻¹ year⁻¹ to offset all emissions of agricultural phases. Mitigating practices can reduce GHG emissions, but compensation via sequestration (soil or biomass C) shall be required to achieve zero GHG emissions. Reserving approximately 10–15% of the farm’s total agricultural production area to plant native trees or eucalyptus in marginal areas or even introducing crop–livestock–forest integration or crop–forest integration systems can offset the GHG emissions of the entire agricultural production phase, considering the potential for soil and biomass C sequestration, showing that it is a feasible option for producing C credit from the agricultural sector. Full article

Mining (1) operations in remote areas (2) face significant challenges related to energy supply, high fuel costs, and limited infrastructure. This study investigates the potential for achieving energy independence (3) and resilience (4) in such environments through the integration of renewable energy sources (5) and battery–electric mining equipment. Using the “Studena Vrila” underground bauxite mine as a case study, a comprehensive techno-economic and environmental analysis was conducted across three development models. These models explore incremental scenarios of solar and wind energy adoption combined with electrification of mobile machinery. The methodology includes calculating levelized cost of energy (LCOE), return on investment (ROI), and greenhouse gas (GHG) reductions under each scenario. Results demonstrate that a full transition to RES and electric machinery can reduce diesel consumption by 100%, achieve annual savings of EUR 149,814, and cut GHG emissions by over 1.7 million kg CO₂-eq. While initial capital costs are high, all models yield a positive Net Present Value (NPV), confirming long-term economic viability. This research provides a replicable framework for decarbonizing mining operations in off-grid and infrastructure-limited regions. Full article

Electricity is a significant factor in the life cycle of many products, so the reliability of greenhouse gas (GHG) emissions data is crucial. The article presents publicly available sources of emission factors representative of Poland. The aim of the study is to assess their strengths and weaknesses in the context of the calculation requirements of carbon footprint analysis in accordance with the GHG Protocol. The article presents the results of carbon footprint calculations for different ranges of emissions in the life cycle of 1 kWh of electricity delivered to a hypothetical organization. Next, a discussion on the quality of the emissions factors has been provided, taking account of data quality indicators. It was concluded that two of the emissions factors that are compared—those based on the national consumption mix and the residual mix for Poland—have been recognized as suitable for use in carbon footprint calculations. Beyond the calculation results, the research highlights the significance of the impact of the selection of emissions factors on the reliability of environmental analysis. The article identifies methodological challenges, including the risk of double counting, limited transparency, methodological inconsistency, and low correlation of data with specific locations and technologies. The insights presented contribute to improving the robustness of carbon footprint calculations. Full article

This article examines the role of managed ecosystems, and particularly forests, in achieving carbon neutrality in Russia. The range of estimates of Russia’s forests’ net carbon balance in different studies varies by up to 7 times. The. A comparison of Russia’s National GHG inventory data for 2023 and 2024 (with the latter showing 37% higher forest sequestration) is presented and explained. The possible changes in the Long-Term Low-Emission Development Strategy of Russia (LT LEDS) carbon neutrality scenario due to new land use, land use change and forestry (LULUCF) data in National GHG Inventory Document (NID) 2024 are discussed. It is demonstrated that the refined net carbon balance should not impact the mitigation ambition in the Russian forestry sector. An assessment of changes in the drafts of the Operational plan of the LT LEDS is presented and it is concluded that its structure and content have significantly improved; however, a delay in operationalization nullifies efforts. The article highlights the problem of GHG emissions increases in forest fires and compares the gap between official “ground-based” and Remote Sensing approaches in calculations of such emissions. Considering the intention to increase net absorption by implementing forest carbon projects, the latest changes in the regulations of such projects are discussed. The limitations of reforestation carbon projects in Russia are provided. Proposals are presented for the development of the national forest policy towards increasing the net forest carbon absorption, including considering the projected decrease in annual net absorption by Russian forests by 2050. The role of government and private investment in improving the forest management of structural measures to adapt forestry to modern climate change and the place of forest climate projects need to be clearly defined in the LT LEDS. Full article