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Integration of module of nitrification in soil active layer in the conceptual hydrological model METQ
2024
Liepa, Sindija | Grinfelde, Inga | Pilecka-Ulcugaceva, Jovita | Bakute, Anda | Burlakovs, Juris
In the world, hydrological models are often used in the modelling of ecological components. In the context of the Paris Agreement and the European Green Deal, it is necessary to develop GHG emission modelling capabilities. The development and refinement of the conceptual model METQ is necessary not only for the quantitative analysis of flow, but in addition to its refinement, it is possible to conduct interdisciplinary research in the subfield of ecohydrology, which studies the interaction of water and ecosystems, and in environmental engineering, which addresses the issues of reducing diffuse pollution and reducing greenhouse gas emissions, technology implementation issues, where water content in the soil and groundwater fluctuations play one of the main roles, for example, in the processes of the formation of nitrous oxide emissions. This paper examines potential GHG emission calculation algorithms used to successfully model GHG emissions from soils, with a particular focus on agricultural soils, which contribute one of the largest amounts of GHG emissions in national emission reports for the agricultural sector. Available algorithms for nitrous oxide nitrification calculations are reviewed and possible algorithms that can be used for modelling emissions from soils and integrated into the conceptual hydrological model METQ are discussed. The developed conceptual solutions for modelling GHG emissions from soils will develop a modelling tool that will be used to estimate the volumes of GHG emissions and evaluate the effectiveness of various GHG emission reduction measures, as well as to perform a complex assessment of the soil GHG balance.
Mostrar más [+] Menos [-]Hydroxy gas as an additive for improvement of exhaust emissions of internal combustion engines — a review
2023
Amatnieks, Kārlis | Birkavs, Aivars | Šmigins, Ruslans
Lowering emissions expelled from internal combustion engines has been the focus of researchers worldwide. Adding hydroxy gas to current internal combustion engines can be an effective way of lowering CO2, CO, HC and particle emissions, as well as improve combustion. Because of this, a review of previously conducted research on the addition of hydroxy gas to different internal combustion engines has been produced. During this review, it was concluded that addition of hydroxy gas can be an effective way of lowering fuel consumption and CO, CO2 and HC emissions in petrol engines, as well as fuel consumption and CO and HC emissions in diesel engines.
Mostrar más [+] Menos [-]Impacts of biocover composition on greenhouse gas emission
2023
Siltumens, Kristaps | Grinfelde, Inga | Burlakovs, Juris | Liepa, Sindija | Grinberga, Linda
It is generally estimated that gas, which generates more than half of the greenhouse gas (GHG) emission from waste industries in landfills, is seen as a serious environmental problem worldwide. It is therefore essential to promote management methods to reduce GHG emissions from landfills as well as other sources. One way of achieving this is the usage of different types of biocover applied to them. The aim of this study is to clarify the impact of the biocover created on GHG emissions. An experiment was conducted in laboratory conditions that studied the effectiveness of biocover developed in the laboratory. Three experimental columns with a diameter of 160 mm and a height of 1500 mm were created. Active compost saturated with water at a thickness of 500 mm was used as a source of methane, a permeable layer of sand at a thickness of 300 mm was further formed and finally covered with biocover. Biocover represented 60% of fine-fraction waste, 20% of soil and 20% of compost. The experiment was launched on June 6, 2022, and the first measurements were made two weeks later. All measurements were performed with the CRDS gas measurement device Picarro G2508 (Picarro Inc., USA California). All data analysis was carried out using Descriptive statistics methods. The largest reduction in emissions is projected directly for methane emissions, as biocover technology is appropriate to reduce methane emissions. Other GHG emissions are also expected to be reduced. NH3 emission measurements were also carried out to investigate the impact of the biocover on it. This experiment shows that the biocover created is effective and can be composed of material that has already been served. The experiment is intended to continue to obtain long-term data on the development of biotransformation and to develop more promising approaches in the future to reduce GHG emissions from landfills.
Mostrar más [+] Menos [-]Transforming agrifood systems to achieve China’s 2060 carbon neutrality goal
2021
Zhang, Yumei; Fan, Shenggen; Chen, Kevin Z.; Feng, Xiaolong; Zhang, Xiangyang; Bai, Zhaohai; Wang, Xiaoxi | http://orcid.org/0000-0001-7927-4132 Chen, Kevin; http://orcid.org/0000-0002-2658-4863 Fan, Shenggen
During recent decades, agriculture has developed rapidly in China, ensuring food security and enriching residents’ diets. At the same time, greenhouse gas (GHG) emissions from the country’s agrifood systems have increased by only 16 percent in the past two decades and fell for two consecutive years in 2017 and 2018. The proportion of GHG emissions in the country’s food systems to the total GHG emissions dropped from 18.7 percent in 1997 to 8.2 percent in 2018. GHG emissions from the Chinese agrifood systems should not be ignored, neverthless. In 2018, GHG emissions from agrifood systems was still as high as 1.09 billion tons CO2eq1. While ensuring food security as the national top priority, measures such as improving agricultural technologies, reducing food loss and waste, and shifting dietary patterns must be adopted to reduce GHG emissions from agrifood systems. Improvements in agricultural technologies are the most effective standalone measures, but the combined three measures above have the most significant effect on GHG emission reduction. Projections show that the combined three measures can redcue GHG emissions by 47 percent in 2060 from the 2020 level. Land use, land use change, and forestry (LULUCF) play a key role as a carbon sink. The carbon sequestration from LULUCF was around 1.1 billion tons CO2eq in 2014. It can increase to 1.6 billion tons of CO2eq per year in 2060, thus LULUCF could completely offset GHG emissions from agrifood systems and still have a surplus capacity to sequester nearly 1 billion additional tons of CO2eq per year, well above the current level of net sequestration,contributing to overall carbon neutrality of China. | Non-PR | IFPRI4; 3 Building Inclusive and Efficient Markets, Trade Systems, and Food Industry; DCA | DSGD
Mostrar más [+] Menos [-]2021 China and global food report: Rethinking agrifood systems for the post-COVID world
2021
Academy of Global Food Economics and Policy, China Agricultural University (AGFEP) | China Academy for Rural Development, Zhejiang University | Centre for International Food and Agricultural Economics, Nanjing Agricultural University (CIFAE) | Institute of Agricultural Economics and Development, Chinese Academy of Agricultural Sciences (IAED) | International Food Policy Research Institute | Fan, Shenggen | Chen, Kevin Z.
During the past several decades, significant progress has been made in reducing global hunger and malnutrition. The number of people suffering malnutrition, however, is rising again. The hidden costs and externalities in the agrifood systems are among the major contributors to various economic, social, and public health crises including food insecurity, zoonotic diseases, climate change, and malnutrition. Compounding the ongoing challenges facing the global agrifood systems, the COVID-19 pandemic, beginning in 2020, has intensified food insecurity and malnutrition in many parts of the world. Global food price indexes increased by more than 27.3 percent from the second half of 2020 to March 2021. Moreover, with many people losing their jobs during the COVID-19 outbreak and therefore facing a dramatic income decrease, the number of people confronted with food crises and extreme poverty increased significantly. Furthermore, the outbreak and prevalence of COVID-19 also increased regional inequalities in global food security, especially in Africa and the Middle East.
Mostrar más [+] Menos [-]Transforming agrifood systems to achieve China’s 2060 carbon neutrality goal
2021
Zhang, Yumei | Fan, Shenggen | Chen, Kevin Z. | Feng, Xiaolong | Zhang, Xiangyang | Bai, Zhaohai | Wang, Xiaoxi
During recent decades, agriculture has developed rapidly in China, ensuring food security and enriching residents’ diets. At the same time, greenhouse gas (GHG) emissions from the country’s agrifood systems have increased by only 16 percent in the past two decades and fell for two consecutive years in 2017 and 2018. The proportion of GHG emissions in the country’s food systems to the total GHG emissions dropped from 18.7 percent in 1997 to 8.2 percent in 2018. GHG emissions from the Chinese agrifood systems should not be ignored, neverthless. In 2018, GHG emissions from agrifood systems was still as high as 1.09 billion tons CO2eq1. While ensuring food security as the national top priority, measures such as improving agricultural technologies, reducing food loss and waste, and shifting dietary patterns must be adopted to reduce GHG emissions from agrifood systems. Improvements in agricultural technologies are the most effective standalone measures, but the combined three measures above have the most significant effect on GHG emission reduction. Projections show that the combined three measures can redcue GHG emissions by 47 percent in 2060 from the 2020 level. Land use, land use change, and forestry (LULUCF) play a key role as a carbon sink. The carbon sequestration from LULUCF was around 1.1 billion tons CO2eq in 2014. It can increase to 1.6 billion tons of CO2eq per year in 2060, thus LULUCF could completely offset GHG emissions from agrifood systems and still have a surplus capacity to sequester nearly 1 billion additional tons of CO2eq per year, well above the current level of net sequestration,contributing to overall carbon neutrality of China.
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