Sequences and organization of the mitochondrial genome have been used as markers to investigate evolutionary history and relationships in many taxonomic groups. The rapidly increasing mitochondrial genome sequences from diverse insects provide ample opportunities to explore various global evolutionary questions in the superclass Hexapoda. To adequately support such questions, it is imperative to establish an informatics platform that facilitates the retrieval and utilization of available mitochondrial genome sequence data. The Insect Mitochondrial Genome Database (IMGD) is a new integrated platform that archives the mitochondrial genome sequences from 25,747 hexapod species, including 112 completely sequenced and 20 nearly completed genomes and 113,985 partially sequenced mitochondrial genomes. The Species-driven User Interface (SUI) of IMGD supports data retrieval and diverse analyses at multi-taxon levels. The Phyloviewer implemented in IMGD provides three methods for drawing phylogenetic trees and displays the resulting trees on the web. The SNP database incorporated to IMGD presents the distribution of SNPs and INDELs in the mitochondrial genomes of multiple isolates within eight species. A newly developed comparative SNU Genome Browser supports the graphical presentation and interactive interface for the identified SNPs/INDELs. The IMGD provides a solid foundation for the comparative mitochondrial genomics and phylogenetics of insects. All data and functions described here are available at the web site http://www.imgd.org/ .

With growing global demand for sustainable decarbonization, hydrogen energy systems have emerged as a key pillar in achieving carbon neutrality. This study assesses the greenhouse gas (GHG) reduction efficiency of Republic of Korea’s hydrogen ecosystem from a life-cycle perspective, focusing on production and utilization stages. Using empirical data—including the national hydrogen supply structure, fuel cell electric vehicle (FCEV) deployment, and hydrogen power generation records, the analysis compares hydrogen-based systems with conventional fossil fuel systems. Results show that current hydrogen production methods, mainly by-product and reforming-based hydrogen, emit an average of 6.31 kg CO₂-eq per kg H₂, providing modest GHG benefits over low-carbon fossil fuels but enabling up to a 77% reduction when replacing high-emission sources like anthracite. In the utilization phase, grey hydrogen-fueled stationary fuel cells emit more GHGs than the national grid. By contrast, FCEVs demonstrate a 58.2% GHG reduction compared to internal combustion vehicles, with regional variability. Importantly, this study omits the distribution phase (storage and transport) due to data heterogeneity and a lack of reliable datasets, which limits the comprehensiveness of the LCA. Future research should incorporate sensitivity or scenario-based analyses such as comparisons between pipeline transport and liquefied hydrogen transport to better capture distribution-phase impacts. The study concludes that the environmental benefit of hydrogen systems is highly dependent on production pathways, end-use sectors, and regional conditions. Strategic deployment of green hydrogen, regional optimization, and the explicit integration of distribution and storage in future assessments are essential to enhancing hydrogen’s contribution to national carbon neutrality goals.

Objectives:This study aims to assess the environmental impact of the composting process, which constitutes 75.3% of the domestic livestock manure recycling methods, and to determine the environmental impacts of methane and nitrous oxide, the major greenhouse gases in the livestock sector, as well as ammonia, a precursor to fine particulate matter that has recently become a social issue. The analysis will focus on the categories of climate change and fine particulate matter formation to identify the most significant factors impacting the environment.Methods:This study applied the Life Cycle Assessment (LCA) methodology according to ISO 14040/14044 standards to evaluate the environmental impact of producing one bag (20kg) of livestock manure compost. The system boundary included the transportation of livestock manure and sawdust to the composting facility and the compost production process. The methodology applied for impact assessment was the ReCiPe 2016 v.1.1 Midpoint (H) method, which allows for a more global evaluation by utilizing worldwide average data.Results and Discussion:The impact assessment of livestock manure compost production revealed that producing one bag contributes 2.667 kg CO2-eq. to climate change, with electricity consumption responsible for 68.95% of emissions. Carbon dioxide (CO2) is the dominant greenhouse gas, making up 84.37% of the total. Particulate matter formation is 0.037 kg PM2.5-eq., with 91.97% resulting from emissions during the composting process. Ammonia (NH3) is the main cause of particulate matter, accounting for 92.02% of emissions.Conclusion:Based on the research, electricity consumption is the main factor affecting climate change in compost production, and ammonia is the primary cause of fine particulate matter. This study provides a case for evaluating the environmental impact of livestock manure composting and can serve as a foundational reference for developing policies and technologies to address climate change and fine particulate matter issues.

Korea has introduced one of the world’s first legally mandated Clean Hydrogen Certification Schemes as part of its national strategy to achieve carbon neutrality by 2050. However, certification outcomes are highly sensitive to methodological choices, making assurance of credibility and fairness a critical challenge. To strengthen robustness, this study compared international life cycle assessment (LCA) guidelines and standards to identify elements applicable for institutional adoption. Thirteen policy-oriented hydrogen LCA studies were reviewed to derive design factors for improving Korea’s scheme. Five core factors of functional units, system boundaries, co-product definition, allocation procedures, and data quality were identified, along with three additional factors of cut-off criteria, GWP (Global Warming Potential), and electricity procurement rules. Analysis of international guidelines revealed uncertainties and barriers to comparability in the Korean scheme. Suggested improvements include specifying pressure conditions in functional unit definitions, predefining co-product lists, stipulating allocation methods differentiated by co-product categories, and establishing data quality criteria for items lacking default values. The additional factors also require refinement. For cut-off rules, clear thresholds and application criteria should be codified. Regarding electricity procurement, ensuring low-carbon integrity requires more granular reporting intervals and explicit rules for calculating emissions from power supplied through energy storage systems. In conclusion, while Korea’s Clean Hydrogen Certification Scheme provides a pioneering framework, refinements are essential to ensure consistency, reproducibility, and international alignment. By systematically identifying uncertainties and proposing improvements, this study contributes to enhancing the credibility and fairness of institutional LCAs for clean hydrogen certification.

Purpose: Shifts in national dietary patterns can significantly influence a country’s water footprint (WF), particularly in water-stressed regions like South Korea. This study evaluates how changes in Korean food consumption between 2008 and 2023 have altered the national dietary WF, using 55 of the most-consumed food items to identify demographic and regional “hot spots” of rising water use and to provide an empirical basis for sustainable food and water policy. Design/methodology/approach: A time-series, consumption-based quantitative analysis was conducted using food consumption data from the Korea Health Industry Development Institute. Daily WF for 55 high-consumption food items was calculated by multiplying per capita daily intake by food-specific WF coefficients, derived primarily from domestic literature and supplemented with global datasets where necessary. The analysis spans 2008 to 2023 and is stratified by urban scale, gender and age group to examine group-level differences in food-related water use. Findings: Despite only modest growth in overall food intake, the total dietary WF increased by approximately 56.7%. This rise was driven primarily by a decrease in rice consumption and a sharp increase in water-intensive animal proteins. Small- and medium-sized cities experienced the largest relative increase (∼127.7%), men consistently exceeded women in WF and the 30–49 age cohort recorded the largest absolute gain. Research limitations/implications: This study acknowledges several limitations. First, we utilized global food WF coefficients based on the typical diet. This approach does not accurately reflect the unique water consumption patterns in South Korea. Consequently, it is vital to develop a WF assessment that is tailored to South Korea’s distinct domestic conditions, cultural practices and dietary preferences. Designing a new WF model that considers the local environment and the food culture of South Korea will yield more precise and applicable results. Second, while this study analysed 16 of the top 30 most consumed foods in 2020 based on consistent data available from 2010 to 2020, the selected foods may not fully represent the overall consumption patterns of South Koreans. To capture a more comprehensive view of water consumption and food intake throughout the country, it is essential to establish a WF for specific Korean foods, such as kimchi, rice cakes, soju and other local delicacies. By developing WFs for all 30 highly consumed food items each year, we can gain an accurate understanding of the water usage associated with the Korean diet. Practical implications: The results urge embedding WF metrics into Korean dietary guidelines, food-labelling schemes and institutional catering programmes, supported by a high-resolution national WF database, a real-time reporting platform and consumer awareness campaigns steering choices towards lower-WF foods. Originality/value: This study is the first to present a demographically segmented, time-series assessment of Korea’s dietary WF. It connects empirical evidence with sustainability policy by showing the need for localised WF metrics and tailored interventions. These findings offer actionable insights for aligning national food systems with sustainable water use and integrated resource management.

This study proposes a method for estimating life cycle greenhouse gas (GHG) emissions of a hydrogen fuel cell house using the Life Cycle Assessment (LCA) framework. Subsequently, a case analysis based on the proposed method was conducted to assess the GHG reduction potential of a hydrogen fuel cell house. To establish the life cycle GHG estimation method, international and domestic LCA-related standards, guidelines, and prior studies were reviewed. The method was evaluated in three sequential components: system boundary definition, data collection, and GHG calculation. The system boundary was established following the modular approach outlined in EN 15804. Data collection was based on case studies from domestic and international research as well as BOM (Bill of Materials) from hydrogen fuel cell house demonstration sites. The GHG calculation involved the formulation of estimation equations for individual items and the identification of applicable databases. Using the proposed method, the life cycle GHG emissions of a hydrogen fuel cell house utilizing reformer-based hydrogen were calculated to be 1.33E+03 kgCO₂-eq/m². A comparative analysis revealed that a hydrogen fuel cell house using clean hydrogen achieved a 20.3% reduction in life cycle GHG emissions compared to the reformer-based hydrogen house and a 19.2% reduction compared to conventional houses. The results indicate that hydrogen fuel cell houses offer emission reduction benefits, but their environmental impact is significantly influenced by the hydrogen production method. Additionally, the study highlights the importance of the transition of conventional houses to hydrogen fuel cell houses and the supply of low-carbon hydrogen for maximizing GHG reduction potential. These findings provide valuable insights for sustainable development of hydrogen-based residential energy systems and contribute to policy discussions on carbon-neutral urban infrastructure