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Contamination problems in former military areas: case study in Riga [Latvia]
2012
Burlakovs, J., University of Latvia, Riga (Latvia) | Gorbunovs, E., University of Latvia, Riga (Latvia)
Contamination of urban areas is directly connected with the lack of adequate waste management planning. Problems mostly arise in former military bases, garages, warehouses and areas with other facilities. For many decades environmental problems caused by pollution in areas of military use were not managed in Latvia. The aim of this research is to assess visual environmental quality and study heavy metal contents in soil of ‘Jaunais Mežaparks’ after demolishing works in the capital of Latvia – Riga, as well as to provide comparison to the former military ‘Daugavgrīva’ site. Research was carried out from November 2011 to February 2012 by soil sampling and further analysis and comparison of the heavy metal content in soil with target and boundary levels in legislation. ‘Jaunais Mežaparks’ is a former military area which is planned to be reused in future. The former military site is planned to be used as the residential neighborhood and is situated close to important recreational object in Mežaparks area – Lake Ķīšezers. According to Riga Development Plan old military sites must be remediated in accordance with environmental legislation if the contamination exceeds critical concentration values. Thus, this case study includes assessment of visual pollution as well as soil heavy metal contamination study. Recommended actions as well as direct remediation technologies to reduce the poisonous impact of contamination to environment in this area are proposed.
Mostrar más [+] Menos [-]Removal of heavy metals from contaminated soils by electrokinetic remediation
2014
Burlakovs, J., University of Latvia, Riga (Latvia) | Stankevica, K., University of Latvia, Riga (Latvia) | Hassan, I., Western University, London, Ontario (Canada) | Janovskis, R., University of Latvia, Riga (Latvia) | Lacis, S., University of Latvia, Riga (Latvia)
Heavy metals as well as other pollutants are widespread and create deleterious impact to the environment and human health. There are different in situ and ex situ technologies of immobilization and removal of contaminants; electrokinetic remediation is one of such technologies. It can be applied for treatment of wide areas, e.g., former industrial and military firing-grounds. Technology is applicable to water soluble contaminants at sites with homogeneous soils that are fine-grained and exhibit both, high permeability and high moisture contents. The aim of the study was to test the efficiency of electrokinetic remediation for copper contaminated clayey soil in laboratory conditions. Pilot scale experiments were applied to test the efficiency of electrokinetic removal of contaminants from soil by application of low voltage direct current (DC). Experimental results show that the use of DC power can be selected for treatment of heavy metal contaminated soils. Batch scale experiments were done by using clayey soil with known physico-mechanical properties, spiked with copper solution of known concentrations. Electric force was changed by varying its parameters. The article gives batch experimental results for diffusion of copper ions in soil under the influence of the external electric field.
Mostrar más [+] Menos [-]Leaching of heavy metals from soils stabilized with portland cement and municipal solid waste incineration bottom ash
2013
Burlakovs, J., University of Latvia, Riga (Latvia) | Arina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Rudovica, V., University of Latvia, Riga (Latvia) | Klavins, M., University of Latvia, Riga (Latvia)
Heavy metals are worldwide spread pollutants in soils of functioning as well as abandoned industrial territories, landfills, military areas with its historical contamination, and other sites contaminated by industrial activities. Development of soil and groundwater remediation technologies is a matter of great importance to diminish the hazardous impact of pollution to humans and environment. Sustainable solution can be found for remediation of industrial areas using the stabilization/solidification (S/S) technology, which refers to binding of waste contaminants to a more chemically stable form. Geotechnical properties of soil treated with Portland cement (PC) can be improved when municipal solid waste incineration (MSWI) ash is used as the combined additive. Ash is composed mainly of metals, so environmental impact must be evaluated if it is used as amendment in the cement industry. The use of MSWI ash in stabilization of contaminated soils would be useful for the sustainable environmental management in two ways: S/S contaminated soil gains better geotechnical stability and waste incineration industry gets rid of the ash with high metal content. The aim of research is to provide pilot batch experimental results for leaching of heavy metal compounds when S/S technology is used for contaminated soils using PC and MSWI bottom ash additives. Mineral soils were spiked with copper, PC and MSWI were added in known proportions and leaching tests applied. Main results show that PC addition allows to chemically stabilizing soil; thus, heavy metals are not leached out from combined mass of spiked soil and MSWI bottom ash.
Mostrar más [+] Menos [-]Phytoremediation as tool for prevention of contaminant flow to hydrological systems
2018
Valujeva, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Burlakovs, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Grinfelde, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pilecka, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Jani, Y., Linnaeus Univ. (Sweden) | Hogland, W., Linnaeus Univ. (Sweden)
This paper aims to deal with the phytoremediation approach for protection of environment and preventing the streaming of contaminant flows to hydrological systems. Phytoremediation is a cost-effective environmentally friendly clean-up technology, which uses plants and microorganisms in rhizosphere for soil and groundwater treatment. Phytoremediation is enhancing degradation of organic pollutants and improving stabilization of inorganic contaminants where plants can be used to treat soil and water polluted with hydrocarbons, chlorinated substances, pesticides, metals, explosives, radionuclides as well as to reduce the excess of nutrients. Selection of species for this type of treatment processes is based on evapotranspiration potential and ability to bioaccumulate contaminants. The project entitled “Phytoremediation Park for treatment and recreation at glassworks contaminated sites” (PHYTECO) aimed at cross-sector international partnership. The challenge of project was to develop remediation strategy where negative consequences from centuries long anthropogenic influence are turned to be something positive – development of the recreation park from the glass dump. New “Knowledge in Inter Baltic Partnership Exchange for Future Regional Circular Economy Cooperation” (PECEC) project is sequential continuation.
Mostrar más [+] Menos [-]Impact of inulin on production of methane, carbon dioxide and gastrointestinal canal functionality in calves
2018
Jonova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ilgaza, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)) | Grinfelde, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zolovs, M., Daugavpils Univ. (Latvia)
Ruminants produce a large amount of methane (CH4 ) and carbon dioxide (CO2 ) in their foregut. These gases cause greenhouse effect. There are a lot of studies about different feed additives which can reduce the production of greenhouse gases in ruminants. Prebiotics can also change the amount of bacteria in animal gastrointestinal tract and reduce the occurrence of diarrhoea. The aim of this study was to test whether the prebiotic inulin affects the production of CH4 and CO2 in calves’ rumen and whether it affects the bacteria count in the rumen fluid and bacterial overgrowth in intestines. We used the flour of Jerusalem artichoke (Helianthus tuberosus L.) containing 50% of inulin. Approximately fifty days old, Holstein Friesian crossbreed calves were used in this study. Eight were in the control group, 8 received 12 g of flour and 8 received 24 g per day. On the 28th and 56th day of the research, we measured the amount of CH4 and CO2 in calves’ rumen took rumen fluid samples for bacterial analysis and urine to measure the level of phenol and indican. We concluded that adding the flour of Jerusalem artichoke at doses 12 g and 24 g did not significantly impact the production of CH4 and CO2 in calves’ rumen, the prebiotic inulin may suppress the growth of anaerobic microorganisms in the rumen at concentration 12 g of inulin reaching 56th day of experiment. The amount of phenol and indican in calves’ morning urine did not correlate with the faecal consistency of calves.
Mostrar más [+] Menos [-]Diet optimization for dairy cows to reduce ammonia emissions
2021
Kreismane, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Aplocina, E., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Naglis-Liepa, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Berzina, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Frolova, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Lenerts, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Feeding livestock a balanced diet with a differentiated crude protein (CP) content, depending on the lactation phase, can reduce nitrogen emissions from livestock excrement and urine. A higher content of non-starch polysaccharides in livestock diets improves feed absorption in the livestock body and, consequently, nitrogen is emitted more from protein present in livestock manure than from urea acid present in livestock urine. The aim of the study is to calculate the ammonia emission reduction potential in Latvia by optimizing the feeding of dairy cows and ensuring life longevity, as well as provide justification for ammonia emission reduction in dairy farms. Calculations made by using the NorFor Model for optimization of dairy cow (Bos primigenius f. taurus) diets revealed that compared with lowyielding cows, a higher CP content diet fed to high-yielding cows at the beginning of lactation increased the amount of nitrogen (N) in their excrement and urine by 90–180 g dE−1. Reducing the CP content in the cow diet by an average of 10 g kgE−1 dry matter (DM) during mid-lactation resulted in the same trend. Reducing the CP content in the cow diet during late lactation and the dry period by another 20–30 g kgE−1 of DM, N emissions from excrement and urine significantly decreased. Increasing the lifespan of dairy cows also means reducing ammonia emissions from the farm. By increasing the number of lactations per cow on dairy farm, it is possible to reduce the number of heifers per cow. The total reduction of ammonia emissions in Latvia was calculated based on a long-term projection of a decrease of 0.1 heifer per dairy cow. Ammonia emissions could be reduced by 0.051 kt by decreasing the number of heifers by 12.54 thou. at the planned increase in the lifespan of dairy cows by 2030.
Mostrar más [+] Menos [-]Data acquisition system for vehicle engine sensors: A review
2024
Melders, Lauris | Smigins, Ruslans | Birkavs, Aivars
Monitoring the operation of car engines using a smartphone and cloud services is a concept that falls within the field of intelligent vehicle technologies. Using information collection system, vehicle fleet companies can effectively manage the usage of their vehicles, minimizing investment and maintenance costs, preventing accidents and failures, identifying poor driving behaviour among employees, and reducing expenses associated with fuel, tires, and other resources. This approach involves collecting real-time data from the vehicle engine sensors, transferring data to the cloud via a smartphone, and then using cloud services to analyse and manage the information, making it understandable in a simple way. This review reflects on the working efficiency of internal combustion engines and the reduction of pollution to the environment, also gathers existing literature to gain insights into vehicle sensor data acquisition technology and systems in the automotive industry identifying gaps in current knowledge and provide a conceptual framework for next practical research in this field. After explaining the general idea of logistics tasks in technology development, various sensors and their methods are associated with engine properties are introduced. The research results show that most articles are about data acquisition systems from different systems. They can provide convenience and flexibility for users, allowing them to easily access and adjust settings on-the-go, enabling real-time monitoring and adjustment of engine performance, helping users optimize efficiency and performance based on their specific needs and preferences.
Mostrar más [+] Menos [-]Nonpoint-source pollution control and greening of China’s agrifood systems
2021
Gong, Binlei; Chen, Kevin Z.; Fang, Xiangming; Meng, Ting; Zhou, Li; Shi, Minjun; Wang, Shuo | http://orcid.org/0000-0001-7927-4132 Chen, Kevin; http://orcid.org/0000-0002-2658-4863 Fan, Shenggen
The unsustainable agricultural production mode of “high input and high output” has imposed a heavy burden on China’s ecosystems, and severely restricted the sustainable development of the country’s agrifood systems. Taking long-term prevention and control of agricultural nonpoint-source pollution as the key approach can play an important role in upgrading country’s agriculture to circular and renewable agriculture-food-ecological system circulation. Currently, the five major sources of agricultural nonpoint-source pollution in China are livestock, poultry and aquaculture; chemical fertilizers; pesticides; crop residues; and waste plastic films. The Chinese government has issued corresponding policies and measures to carry out prevention and control at the source and end, which have achieved initial results. Its accurate grasp of policy direction and policy implementation provide lessons for other developing countries. Several years of treatments have resulted in remarkable reduction of nitrogen and phosphorus emissions from the livestock and poultry farming, but the pollutant emissions of the aquaculture are increasing, and the utilization rate of chemical fertilizers and pesticides is still relatively low compared with that of developed countries. China mainly relies on policies and legal means, and government subsidies to control agricultural nonpointsource pollution in the short term. However, more emerging options should be explored to establish a long-term mechanism to prevent and control agricultural nonpoint-source pollution and to transform the agrifood systems to become even greener, including property rights arrangements, interprovincial ecological compensation, green finance, and brand building for ecological agricultural products. | 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 [-]Nonpoint-source pollution control and greening of China’s agrifood systems
2021
Gong, Binlei | Chen, Kevin Z. | Fang, Xiangming | Meng, Ting | Zhou, Li | Shi, Minjun | Wang, Shuo
The unsustainable agricultural production mode of “high input and high output” has imposed a heavy burden on China’s ecosystems, and severely restricted the sustainable development of the country’s agrifood systems. Taking long-term prevention and control of agricultural nonpoint-source pollution as the key approach can play an important role in upgrading country’s agriculture to circular and renewable agriculture-food-ecological system circulation. Currently, the five major sources of agricultural nonpoint-source pollution in China are livestock, poultry and aquaculture; chemical fertilizers; pesticides; crop residues; and waste plastic films. The Chinese government has issued corresponding policies and measures to carry out prevention and control at the source and end, which have achieved initial results. Its accurate grasp of direction and implementation provide lessons for other developing countries. Several years of treatments have resulted in remarkable reduction of nitrogen and phosphorus emissions from the livestock and poultry farming, but the pollutant emissions of the aquaculture are increasing, and the utilization rate of chemical fertilizers and pesticides is still relatively low compared with that of developed countries. China mainly relies on policies and legal means, and government subsidies to control agricultural nonpointsource pollution in the short term. However, more emerging options should be explored to establish a long-term mechanism to prevent and control agricultural nonpoint-source pollution and to transform the agrifood systems to become even greener, including property rights arrangements, interprovincial ecological compensation, green finance, and brand building for ecological agricultural products.
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