Journal of Central European Green Innovation
Review of Sewage Sludge Composting Technologies
The recycling of wastewater residues plays a crucial role in the circular economy, a key focus of the EU's 2030 Green Deal. A byproduct of wastewater treatment, sewage sludge, can serve as a sustainable resource for plant nutrition through the application of various composting technologies. Composting helps mitigate pollution by converting organic waste, such as sewage sludge, into compost with the aid of microorganisms. The resulting compost enhances soil quality and health. Several composting approaches—windrow composting, aerated static windrow composting, vermicomposting, and in-vessel composting—each have unique advantages and disadvantages in terms of environmental impact, efficiency, and sustainability. This paper provides an overview of composting methodologies and explores advanced composting technologies for optimizing sewage sludge composting. Aerobic composting is the most widely used method due to its efficiency and ability to eliminate pathogens; however, concerns remain regarding greenhouse gas emissions and nutrient losses. To address these challenges, co-composting, vermicomposting, and two-phase composting have been developed to enhance compost quality and shorten processing times. Despite these advancements, land restrictions, complex technologies, and high costs remain significant limitations. This study emphasizes the importance of microbial dynamics, pathogen elimination, and compost maturation during key composting stages, from the mesophilic to the thermophilic phase, in order to produce stable, nutrient-rich compost. While composting technologies align with sustainability goals, further research is needed to improve efficiency, reduce emissions, and assess potential economic impacts. This review highlights the critical role of composting in achieving waste management and environmental sustainability objectives.
Copyright (c) 2025 Journal of Central European Green Innovation https://creativecommons.org/licenses/by-nc-nd/4.0
Study on the Physiological Characteristics of Sunflower Treated With Bacterial Fertilizer
In 2019, in the experimental area on Kompolt, we tested the effect of Mikro-Vital in sunflower crops in a large-plot experiment using 2 doses (1 l ha-1 and 2 l ha-1). The bacterial fertilizers were applied to the chernozem brown forest soil at sowing. At the beginning of July, before flowering, the relative chlorophyll content of the leaves was measured in vivo with field instruments (portable spectroradiometer and SPAD) and spectral vegetation indices were determined, which, in addition to photosynthetic processes, allow us to infer the stress tolerance of the plants and the nitrogen and water content of the leaves. These parameters are the most important determinants of fertility. We also measured the average yield at harvest. In the year of the study, weather conditions were not ideal for sunflower development. The minimal rainfall in spring resulted in poor crop development after sowing. Chlorophyll vegetation indices also indicated a significant positive effect of the bacterial fertilizer treatment, and photochemical activity (PRI), leaf water content (PWI) were higher compared to the control plots. In the control treatment, stress sensitivity (SIPI) and the amount of protective pigments (CRI, ARI) were higher. Water shortages also occurred at flowering, resulting in a medium average yield for all plots, which was lower than the average of Heves County, Northern Hungary and the country. Based on our tests, a treatment of 1 l ha-1 is considered optimal.
Physiological Characteristics of Wheat Cultivars Treated With Soil Bacteria in a Small-plot Experiment
This paper presents the results of small-plot field experiment conducted in 2022, a year of severe drought, with soil bacteria-treated wheat cultivars, during which we examined photosynthetic pigments, average yield, and certain quality parameters using in vivo methods. The soil microbe preparation used is especially recommended for use in warn, drought period, and it is also effective for seed treatment. Its use can be expected to result in better nutrient and water supply, more homogeneous stands, and increased stress tolerance. At the beginning of flowering, the SPAD, EVI, RDVI indices, which indicate chlorophyll content in leaves were significantly higher in three varieties (Mv Nemere, Mv Kondás, Mv Pelsodur), while at the same time, these varieties showed higher photochemical activity (PRI), lower stress sensitivity (SIPI), and lower carotenoid content (CRI). Water content was higher in treated individuals for all varieties. For all 8 varieties, the average yield was approximately 10% higher on the treated plots, Mv Nemere. The nutritional values were only of medium quality, but all quality parameters on the treated plots showed better results. The quality parameters indicated only medium quality, but we obtained better results for all quality parameters on the treated plots. Overall, it can be said that the product can be used effectively even in a drought year, but at the higher dose recommended by the manufacturer.
Examination of the Effect of Complex Nutrient Supply on Yield and Quality of Winter Wheat
The climate of our country is suitable for wheat cultivation everywhere, but there is variation from one region to another. Nowadays, the greatest risk in wheat production is posed by extreme weather conditions, but next to them the other key issue of successful growth is the correct nutrient supply. In the present work, the results of the nutrient supply experiment conducted in 2017 and 2022 at the Research Institute of Kompolt of the predecessor institution of MATE are presented. The experiment was set up on small plots, in 4 replications, with Latin square arrangement. In the experiment the effect of NPK doses were examined on the growth of the plants and on the yield in four treatments (three levels of nutrient supply plus control treatment). Each plot was divided into two parts, and one part of each treatment was supplemented with foliar fertilization. The main goal of our experiment is to determine the optimal amount and content of fertilizer, which can give the highest yield in different crop years among the given ecological conditions. We measured the plant height at full maturity, the amount of the yield and the different quality parameters. We found that the highest yield was given by treatment of “growing area specific” fertilizer supplemented with foliar fertilizer.
The Effect of Seasonal Groundwater Level Rise on the Zeleny Value of Winter Wheat
The topic of the research is to examine the effect of temporary waterlogging on winter wheat under controlled, lysimeter conditions. The aim was to analyze plant responses specifically yield and the Zeleny value at different water levels of 0 cm (two-phase soil), −30 cm (water level set at 30 cm below the surface), and −60 cm (water level set at 60 cm below the surface) and durations (3, 6, 9, 12 days). The statistical methods used MANOVA, ANOVA, Welch’s test, the Games-Howell post-hoc test, and multivariate correlation helped map significant differences in the results. The Pearson correlation matrix confirmed a highly significant, strong positive correlation between the quality indicators (r = 0,955-0,989, p < 0,001), whereas yield showed a weak positive correlation with the quality parameter (r = 0,155). According to the Games-Howell post-hoc tests, for the Zeleny value, moderate stress particularly the 9-day treatment at a −60 cm water level significantly improved quality (e.g., 2021, −60 cm, 9 days vs. 3 and 6 days: p = 0,031 and p = 0,004). Under the same conditions (e.g., 2021, −60 cm, 9 days), yield did not differ significantly from the control according to Welch’s t-test (p = 0,4032). Quality improvement is not necessarily associated with yield increase; indeed, in other cases yield may even decrease. In 2021, at the 0 cm water level, the 6-day treatment significantly reduced yield (p = 0,0496), while the 9- and 12-day treatments increased it (p = 0,009, p = 0,034). Zeleny value: in 2020 at −60 cm, the continuous treatment was significantly worse than the 12-day treatment (p = 0,004), whereas in 2019 at the same water depth, the continuous treatment was significantly better than the 3-day treatment (p < 0,0001). For yield, in 2021 at −60 cm, continuous flooding resulted in a significantly lower yield than the 12-day treatment (p = 0,005). Conversely, in 2020 at −60 cm, the continuous treatment was significantly better than the 3-day (p = 0,026) and 9-day (p = 0,003) treatments. This pattern underscores the risky and year-specific nature of continuous treatment.
Impact of outdoor units of heat pumps and air conditioning equipment on ambient air
Heat pumps (HPs) and air conditioning (AC) systems have become key technologies in reducing energy consumption and greenhouse gas emissions. Their efficiency and comfort-related benefits have been widely studied; however, the environmental impact of their outdoor units—particularly their effects on ambient air quality—has received less attention. The fans of outdoor units generate local airflows that can influence both temperature distribution and the concentration of air pollutants, primarily particulate matter (PM). We conducted long-term observations of air quality on balconies connected to dormitory rooms, focusing mainly on PM concentration. In cases where the outdoor unit of the air conditioner was installed on the balcony, a measurable “cleaning effect” was observed. Depending on the operating mode of the unit, its impact on the ambient temperature was also detectable.
On the Applicability of Machine Learning Methods for Vibration-Based Predictive Tool Maintenance: A Case Study
This study presents a machine learning–based approach for predicting tool wear and preventing tool breakage using vibration diagnostics in machining processes. By analysing vibration signals (and, where applicable, acoustic emission), the proposed method enables early fault detection and supports predictive maintenance strategies. The approach contributes to sustainable manufacturing by reducing material waste, improving resource efficiency, and extending tool lifetime. Experimental results demonstrate that vibration features effectively distinguish between normal and abnormal tool conditions, highlighting the potential of AI-assisted diagnostics in green innovation and Industry 4.0 applications.
A Comparative Environmental Assessment of Direct, Indirect, and Mixed-mode Solar Dryers
The present study offers a comparative environmental assessment of direct, indirect, and mixed-mode solar dryers to identify the most sustainable drying technology. Solar dryers are promising alternatives to open sun drying and fossil-fuel-powered dryers. They are also well-suited for rural areas in developing countries due to the widespread availability of solar energy. This analysis focuses on material sustainability, carbon footprint, and drying and energy efficiency. Direct solar dryers (DSDs) are simple to construct and can be made using locally available materials. However, they suffer from poor temperature control and low efficiency, which can negatively affect the quality of food products. Indirect solar dryers (ISDs) offer better performance than DSDs but involve additional components, making them more expensive to construct. Mixed-mode solar dryers (MMSDs) have the shortest drying time and the highest drying efficiency. However, they also have the greatest environmental impact due to their complex structure and high material requirements. There is a need to balance affordability, environmental impact, and performance in solar dryer designs to serve rural farmers in developing countries effectively. Future studies should focus on integrating localized and eco-friendly materials into solar dryer construction.
Water-Based Cooling in PV Systems: A Statistical Comparison of Modified PV-T and Conventional PV Panels Under Variable Flow Rates
This study explores how well a modified photovoltaic (PV) panel with a water-based cooling system performs under various environmental conditions. We compared a standard PV panel to one enhanced with copper pipes and aluminium adhesive, testing two different flow rates (4 l/min and 7 l/min) to see how solar irradiance and ambient temperature affect the working temperature. Our findings revealed that lower flow rates made the panel more sensitive to environmental changes, with solar irradiance and ambient temperature accounting for up to 92.5% and 80.2% of the temperature variation, respectively. The ANCOVA analysis confirmed that flow rate, solar irradiance, and ambient temperature all significantly influence the working temperature, with flow rate having the strongest impact. The results also showed a significant interaction between flow rate and irradiance, indicating that cooling effectiveness changes with sunlight intensity. However, the interaction between flow rate and ambient temperature was not significant, suggesting that the effect of flow rate remains consistent across different air temperatures.
Identification of microplastic-associated microbial communities from various stages of wastewater treatment and recipient surface waters using MALDI-TOF mass spectrometry
Recent studies have identified microplastics (MPs) in wastewater as surfaces that facilitate microbial colonization and act as vectors for the dissemination of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARBs). Their presence throughout the wastewater treatment process highlights the importance of investigating the microbial communities associated with MPs in wastewater treatment plants (WWTPs) and their potential implications for environmental and human health. This study investigates microbial colonization on MPs in wastewater by sampling six types of MPs deployed at various phases of wastewater treatment in three different WWTPs across Hungary, between June 2024 and March 2025. MPs were incubated in plastic colonizers submerged in treated and untreated wastewater. Post-retrieval, MPs were processed using selective media to ARBs, using Chromatic agar plates and selective medium for Pseudomonas aeruginosa. Strains were identified by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) at the genus level. Based on our results, Stenotrophomonas, Aeromonas genera, and members of the Enterobacteriaceae family were the dominant antibiotic-resistant bacterial taxa associated with MPs.
Impact of Construction Technology on Air Quality
Polluted air can be the causing factor of several diseases, including dementia and type 2 diabetes. One of the indicators of pollution is particulate matter (PM) concentration. In this paper, we investigate air pollution with a focus on PM10 and PM2,5 values. A device capable of measuring PM concentration has been installed in the 23rd district of Budapest. It is placed in a garden of the Virágvölgy residential complex, where construction work is continuously underway. The goal of this paper is to measure the degree to which the ongoing construction work affects the air inhaled by the residents of the complex. Based on the data gathered from the installed device, we analysed the trend of PM values over time. We have compared this to official measurements, regulatory limit values and recommendations by the WHO. We also examined the relationships between PM concentrations and weather factors, as well as the impact of rain on them. We aim to emphasize the importance of regularly monitoring air quality and the need to reduce air pollution.
Copyright (c) 2024 Journal of Central European Green Innovation https://creativecommons.org/licenses/by-nc-nd/4.0
Testing of Apple Cold Storage Technology to Reduce Food Waste
Proper storage of apples in terms of maintaining quality is crucial for both consumers and for the efficiency of the food industry. This research explores Apple storing methods and possibilities, primarily focusing on different storage conditions from the customers' perspective. The aim is to examine the effect of various storage conditions on the physical and chemical properties of apples in detail, and their shelf life, with particular attention to the differences between commercial and home storage. We bought Golden Delicious apples commercially and stored them at two temperatures (+5°C and +10°C), simulating consumer behaviour, at the Fruit Growing Department of the Buda Campus of the Hungarian University of Agriculture and Life Sciences. Sustainable food production and consumption are increasingly important in our everyday lives. Exploring appropriate storage methods reduces food waste and promotes more sustainable food consumption. If consumers can store apples properly at home, less fruit goes to waste. In addition to increasing greenhouse gas emissions, food waste from food degradation also means wasting resources used in production and transport. Exploring appropriate home storage methods will not only help preserve the quality of apples and reduce energy consumption, but also reduce food waste.
Cold Storage Effects on Ethylene Emission, Co₂ Accumulation, and TSS Variation in Golden Delicious Apples at 3°C
The study investigates the ethylene production and respiratory metabolism of Golden Delicious apples stored at 3°C for 13 weeks. Apples were all picked at a maturity stage corresponding to the commercial harvest date and stored at 3°C with a relative humidity of 85±5 %. The results showed that TSS increased at the beginning of the storage while the ethylene release increased slowly under the 3⁰C cold storage. The results of this study show that after 7 weeks of storage, the ethylene release rate peaked at 35.5 μL∙kg-1∙h-1, followed by 14.9 μL∙kg-1∙h-1 after 11 weeks. Then it progressively reduced and remained at a low level. Fruit respiration rate decreased during cold storage at 3⁰C and gradually rose after storage. The goal is to develop strategies to extend the shelf life of apples while reducing post-harvest food waste. By reducing food waste, we reduce the ecological footprint of apple cultivation.
Monitoring of Potassium Content in Wastewater Treatment Plants
Partially treated wastewater can potentially provide a reliable and constant source of water and nutrients for hydroponic crop production. It is essential to determine the macronutrient content of the effluent, such as nitrogen (N), phosphorus (P), and potassium (K), to maximize the yield. Nitrogen (N) and phosphorus (P) measurements are essential daily tasks to be fulfilled, measurements were applied for multiple sources of K content only in this study, determining the exact daily content and concentration pattern. Influent and effluent K levels were measured separately. According to measurements, it was observed that the concentration of K decreased significantly during treatment, with varying values as the wastewater passed through different treatment stages. Two locations with dissimilar technologies were sampled: Etyek, Hungary, semi-continuous batch system with suspended sludge, and South-Pest, Hungary, a continuous activated sludge system. The results were 39,7 mg/l in the influent and 7,5 mg/l in the effluent in Etyek, while South-Pest contained 28,9 mg/l in the influent and 24,5 mg/l K in the effluent respectively. Furthermore, the potassium content was measured in the Return Activated Sludge (RAS) line of South-Pest and found 50,8 mg/l concentration, however, it is being removed from wastewater with the Wasted Activated Sludge (WAS) in activated sludge systems.
The Effect of the Nitrogen Fertilisation on the Sap-sucking Herbivorous Insects (Insecta, Hemiptera) and on the Host Plant Tolerance
In this article the available information on the effects of host plant’s nitrogen fertilisation on the preference/performance of the sap-sucking insects (Hemiptera) and on host plants tolerance is reviewed. There is a very strong general tendency that nitrogen fertilisation increases the preference/performance of the sap sucking insects. Important exceptions are known, when the excessive nitrogen fertilisation decreases the preference/performance of the hemipteran herbivores. Host plant tolerance usually improves with nitrogen fertilisation: exceptions are known when the herbivore is very efficient in exploiting the host plants nitrogen content. Relationship is affected by the host plants and herbivore’s genotype and by the type and the mode of application of the fertiliser. Direct underlining causes are complex and still not entirely known. Nitrogen fertilisation can affect the herbivore through changing the concentrations and ratios of the available nutrients in the plants and/or changing the concentrations of the host plant’s defensive chemicals.
Examination of Red Clover Optimum Harvesting Status in Seed Production With Unmanned Aerial Systems (UAS)
Red clover is the second most valuable and intensively produced leguminous fodder crop in Hungary. Optimum harvesting should start when 75-80 per cent of seed-heads are brown and 90 per cent or more of the seeds are past the hard-dough stage of maturity. Harvesting must be done before an appreciable amount of seed-head deterioration begins. On fall plantings the first-year crop normally matures during the months of August and September. Seed from second-year stands, if not cut back, will mature somewhat earlier. The harvesting of red clover is divided into two distinct operations: (1) the curing or preparation and (2) the hulling and separation of the seed. The curing is by windrowing or contact desiccant spraying. It is the timing of each step that can make all the difference between a good yield and a mediocre one. The agronomists decide those actions with personal on-site inspections of the heads. Their decisions rely on random point sampling. A trend has developed with the recent interest in the harvesting time estimation of red clover in seed production to meet the demands of sustainable and precise agriculture. Unmanned aerial systems (UAS) are one of the current state-of-the-art tools when it comes to supporting farm-scale phenotyping trials. In this examination, we explored the red clover seed heads classification using deep learning on a UAS RGB aerial image. We assessed different ripening status of the flower heads with a single-shot detector (SSD) deep learning model. It is proposed that drone data collection was suggested to be optimum in this study, closer to the harvest date, but not later than the ageing stage. With SSD model we can calculate the number of heads on the vegetation surface but to differentiate them (e.g., purple-, light-brown-, dark-brown flower heads) with high confidence, we need more examinations, spectral bands or fine adjustments of the model with additional data.
Methodology for Measuring the Temperature Conditions in the Outdoor Unit of a Heat Pump
Heat pumps are becoming increasingly widespread as a heat source for ambient air. The energy density of air as a heat source is extremely low, so a large amount of it has to be passed through the heat exchanger of the outdoor unit. For this reason, care must be taken when installing the outdoor unit to ensure that nearby buildings and structures do not interfere with the air flow. If the installation conditions are not suitable, a hydraulic short circuit may occur between the intake and exhaust sides, resulting in a drop in the temperature of the intake air. This phenomenon has a direct impact on the COP (Coefficience of performance) that can be achieved. Given that this phenomenon is not observable to the naked eye, a measurement procedure has been developed to detect and measure this phenomenon. Our aim is to develop a method that can be implemented with the simplest possible measurement procedure, with the fewest possible sensors, but which gives results of sufficient accuracy for practical applications. This will allow the environmental parameter analysis of previously installed outdoor units of heat pumps, with particular reference to temperature conditions.
Mathematical Modelling of Heating With Renewable Energy in a Solar Pot
The subject of this research is the solar pot, a new invention. It became protected at the Hungarian Intellectual Property Office as a utility model (patent number 5489) in 2021. The solar pot can be used to cook food or heat liquids. It has a similar jacketed structure to a tube-in-tube heat exchanger. It has an outer jacket and an inner cooking space. The solar pot has been manufactured but not tested yet through modelling and simulation or with measurements or experiments. These kind of examinations represent a completely new field of research. This paper aims to create a mathematical model for the solar pot, which allows the calculation of the pot's temperature. The modelling and the first results of the simulation based on it are presented. Based on the results, conclusions can be drawn regarding the applicability and efficiency of the solar pot. The environmentally friendly pot can perform cooking tasks. Its use reduces carbon dioxide emission by 247 g on one cooking occasion. Future research plans include assembling an experimental solar pot and solar collector system and creating additional models of the system and the system elements. Measurements will be made on the experimental system under different conditions, which allows the assessment of the applicability and functionality of the pot and the validation of the mathematical models.
Composition of Waste From Seagoing Ships
In shipping, great attention is paid to reducing environmental impacts. This is all the more justified as the most common marine fuel today is heavy fuel oil, which contains 3,500 times more sulphur than conventional diesel fuel. Accordingly, there are now floating hotels in worldwide that use LNG as a green fuel. In this article, we will try to gather literature strongly related to this topic to develop a detailed technology for disposing of these wastes in a later work.
Potenciális szennyezők monitorozása a Közép-Tisza szakaszon vízhigiénés szempontból
In recent decades, the classical bacteriological monitoring of our surface waters has gradually lost its importance, while the increasing water usage (for example for bathing, irrigation, receiving waste water and thermal waters), poses a growing health risk that is further increased by example weather conditions. The majority of wastewater treatment plants regularly struggle with sudden, heavy precipitation, which is received mixed with the wastewater. Most wastewater treatment plants do not have the capacity to store this large volume, so it is often discharged into our surface waters without sufficient treatment. Based on these trends, monitoring-based analysis of surface waters are developing towards a risk-based approach and microbial source tracking. In 2020, based on the monitoring activity carried out on the Middle Tisza section, we detected a pollution source, which could represent a real health hazard under specific hydrological conditions. The investigation also highlighted that knowledge of the appropriate hydrological conditions and water quality may facilitate the appropriate decision-making process.
The Effect of Plant Conditioners on Some Physiological Parameters of Maize in a Drought Year
At Kompolt, since 2015 we have been testing environmentally friendly nutrient supply methods for arable crops. The utilisation of the nutrients depends on the amount and distribution of rainfall during the growing season. In 2022, there was an extreme drought in Hungary, with rainfall from May to September 60-80% below the 40-year average, which resulted in failures of maize yield in many parts of the country. In the given year, we set up experiments with 3 different plant conditioners (1. amino acids, 2. P+Zn+K+Mo, 3. ion Zn) on maize cultivars and measured some photosynthetic parameters with different plant sensors, moreover the yield and corncob parameters at harvest. The SPAD index and spectral vegetation indices, which determine some physiological features, showed a positive effect of all three treatments at the beginning of flowering. Yield were 155 and 159% higher in the first two treatments and 144% higher in treatment 3 compared to the control. Based on corncob parameters, all three treatments showed significantly better results than the control. The largest difference was measured for treatment 2, based on all parameters tested, where foliar fertilizers supplemented with macro- and micro elements in addition to amino acids. Overall, plant conditioners applied at the right time can reduce the effects of environmental stress on plants, and the sensors used can monitor the effects of treatments throughout the growing season.
Life Support Systems (LSS) in the Aquaristics
In this manuscript, life support systems (LSS), which play a major role in aquaculture, are examined in detail; the mechanical units involved, the design of the technology suite, and the results of the measurements and their evaluation during the research are presented. Such systems are not only required for recreational marine pools, but also play an important role in the management of endangered and protected species under artificial conditions. Keeping aquatic organisms in artificial conditions is a very sensitive area. It is axiomatic that in natural environments, organisms have all the environmental conditions - chemical, biological and physical - that they need to maintain their basic life functions and reproduce. In the case of artificial animal husbandry, these natural conditions are often limited. The biggest problem with this is that the well-being of animals depends on human decisions from the moment they enter such a system. This dependency creates a huge responsibility for caretakers.
Comparison of the Quaternary Treatment Technologies in Municipal Wastewater Purification
The removal of micropollutants during wastewater treatment is an essential element of pollution control due to the last amendment of the Directive 91/271/EEC. Reducing and control at the source is usually the most cost-effective measure for a given substance or group of substances, but wastewater treatment plants with load above 150.000 PE (and between 10.000 and 150.000 PE based on the recieving watercourse or environmental risk assessment) have to reduce and remove the micropollutant in the future. The treatment plants have to install technologies which are optimal to eliminate the micropollutant (fourth stage or quaternary treatment technologies). The main quaternary treatment technologies are the different form of activated carbon filtration, membrane technologies (e.g. nanofiltration or reverse osmosis) and Advanced Oxidation Processes, AOP (e.g. ozone treatment). Among the options available for the removal of micropollutants, the most cost-effective solutions are activated carbon processes, ozone treatment, and their combination in different process configurations. At present, the combination of ozone treatment and activated carbon filtration is an effective technology to degrade the micropollutants, also the antibiotic resistant genes, and also remove the harmful by-products from the AOP treatment. For each wastewater treatment plant, it is necessary to individually examine which technology will be the most optimal to accomplish the new requirements.
Dehidrogenáz enzimaktivitás, mint a talajkímélő művelés és takarónövény alkalmazás hatásának korai indikátora
Az ökológiai gazdálkodás pozitív hatását a talaj termékenységére számos kutatás igazolta. További javulás érhető el a talajegészségében, ha az ökológiai gazdálkodásban a talajművelés minimalizálása és a talaj folyamatos növényi borítottsága is hangsúlyos célként fogalmazódik meg. A hagyományos talajvizsgálatok elsősorban a talaj kémiai tulajdonságait, a tápanyag- ellátottságát vizsgálják és figyelmen kívül hagyják a talajt, mint olyan élő rendszert, ami hozzájárul a növény folyamatos táplálásához, egészséges fejlődéséhez, meghatározva a termés beltartalmi és táplálkozás élettani tulajdonságait is. Jelen kutatás a forgatás nélküli művelés és a takarónövények alkalmazásának rövidtávú hatását vizsgálja néhány talajbiológiai tulajdonság változására. Teszteltük a talajok dehidrogenáz (DHA) és fluoreszcein-diacetát (FDA) hidrolízissel kimutatható enzimaktivitását, továbbá a mikorrhiza gombák glomalinnal összefüggő talajfehérjéinek könnyen kinyerhető formáját. A három évig tartó ökológiai gazdálkodási kísérletben egy hagyományos szántásra alapozott művelést (SZ) hasonlítottunk össze forgatás nélküli műveléssel (K) és azt kiegészítve takarónövények alkalmazásával (KT). A talajok biológiai tulajdonságai közül a DHA enzim aktivitásban találtunk szignifikáns különbséget a KT kezelésben (+47,4%). Az FDA enzim aktivitásban, a tápanyag tartalomban (NPK), a glomalin tartalomban (EEGRSP) két év alatt még nem volt kimutatható változás a különböző talajkezelések között. A változatos összetételű takarónövény-keverék már rövidtávon is kifejtette hatását a DHA enzimaktivitáson keresztül. Az eredmények a talajegészség módszerek összehangolt, következetes és kombinált alkalmazásának a szükségességét is alátámasztották.
Intraspecific Facilitation Through Host Plant Quality Improvement? Observations on the Aggregation Behaviour and Population Biology of the Senescence Inducing Phloem Feeder (Ischnodemus Sabuleti)
The aggregation behaviour and the senescence inducing effect on its host plants (Glyceria spp.) of the European chinch bug (Ischnodemus sabuleti) is documented in several Hungarian high- density populations. The hypothesis of intraspecific facilitation through host plant quality improvement is formulated and discussed in detail. We suggest that drought stressed host plants improve the performance of I. sabuleti and facilitate the local population outbreaks. We suggest that the optimal host plant drought stress level is higher for senescence feeding herbivores than for the flush feeding herbivores.
Copyright (c) 2023 Journal of Central European Green Innovation https://creativecommons.org/licenses/by-nc-nd/4.0
Mathematical Modelling of the Internal and External Piping Configurations Effect on the Solar Thermal System
Countless types of renewable energy can easily be exploited like wind, biomass, and solar. The most common power is solar power; it is usually used to get various outputs like electricity generation by photovoltaic/thermal power plants and local water heating. The task is to introduce environmentally friendly technologies, so the government authorities worldwide motivate the use of solar domestic water heating for its primary usage, low upkeep requirements, and the efficiency of the solar heating systems. Domestic solar hot water units, if effectively designed, are competent in providing most hot water demands in an appropriate environment and cost-effective approach. Despite 50 years of development, business technology has certainly not yet achieved substantive market penetration instead of mainstream electric power and gas alternatives. Various stakeholders will consider solar power heating systems utilised in buildings as an attractive alternative to traditional space and water heating methods. However, their functionality depends on climatic conditions, typical water heating requirements, and even operational parameters that could provide chances for performance optimisation. This study aims to analyse the effect of piping parameters on the solar system in the city of Budapest, Hungary using two programs, T*SOL as a solar system simulator and R-Studio as coding software. The analysis uses the simple model of the solar water heating system considering the following factors (pipe diameters, internal length, external length, Glycol, Thickness, volume flow rate, insulation), aiming to study the effect of the internal and external piping system. The study is carried out by simultaneously changing the values of the variables mentioned above by applying linear modelling and changing the collector type to choose the most appropriate system from the solar fraction aspect.
Copyright (c) 2023 https://creativecommons.org/licenses/by-nc-nd/4.0
Examination of a Mobile Platform Suitable for Production and Periodic Storage of Renewable Energy
One of the largest problems of our time is the constantly growing demand for energy and its satisfaction. Humanity obtained this energy primarily by burning fossil fuels, and obtains it so even today. This is the case to be expected for a long time to come, despite of the rise of alternative energy sources. However, there is significant difference between fossil energy sources. Hydrogen and biogas, for example, have much smaller impact on the environment than traditional sources of energy. By combining these with renewable sources, such as solar energy, the environmental impact can be further reduced, and the typical problems of renewable energy sources, the temporal difference between energy production and consumption and the storage of energy, can also become manageable. The goal of my work was to investigate the possibility of an energy-producing and energy-storing device that produces hydrogen using solar cells. After storage, this can be used alone or mixed with biogas to produce electricity in a mobile, containerized design. This allows us to store solar energy and use it in the form of electricity at any time. I examined five versions, during which I performed their energetic analysis and comparison, as well as the related economic calculations. The large, gas mixture using version proved to be the best. It had the lowest specific cost regarding electrical power, and the second lowest regarding stored energy. Taking into account the payback time of the investment too, which was the shortest for this version, it proved to be the only version that is economically feasible at present. Its only notable drawback is that it can only be used where there is sufficient amount of biogas provided from an external source.
Analysis of Phosphate Adsorption Based on Acid-base Processes
In our investigations - we developed a simple method to examine the surface ion exchange processes - where we could measure the amount of hydrogen and hydroxide ions leaving the surface of soil particles by bound phosphate ions. This type of analysis has been followed in the literature with a change in pH - which provides much less accurate results than the calculation of the surface ion balance. Soil samples were shaken with KH2PO4 solution in three replicates with P contents of 0 - 4 - 8 - 12 - 16 - 20 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 88 - and 100 mg/l. After two hours of shaking and centrifugation P content of samples was determined by photometry. The phosphorus concentration of the equilibrium solutions was used to determine the adsorption isotherm of soil phosphorus. The hydrogen ion content was determined from the separated equilibrium solutions and the original solutions used for adsorption using a high-sensitivity potentiometric titrator designed in our lab - with the addition of 0.01 M NaOH solution. The titration curves obtained for small amounts of dilute solutions - which are difficult to evaluate by other methods - were evaluated using a computer program developed in-house to determine the inflection points of the curve - i.e., the equivalence points. The missing amount of hydrogen ions from the solution was plotted as a function of the amount of phosphorus bound. Data shows that the change in the hydrogen ion content of KH2PO4 solution added to the soil - measured after equilibrium - is equal to three times the number of moles of phosphate ions bound. The slope of the fitted line was 0.35 and the correlation coefficient was 0.95. This means that each mole of phosphate bound is associated with the desorption process of three moles of OH- ions or the equivalent of three moles of H+ bound. Formally - this molar ratio expresses the binding of uncharged phosphoric acid molecules on the soil surface. Based on our measurements - several binding mechanisms for the binding of different hydrogen phosphate ions can be assumed under the given conditions. The findings indicate that some chemical reactions can be ruled out - although others could be established. During the adsorption of phosphate forms - only ion exchange reactions occur at the soil surface - which do not involve a change in surface charge - and the various hydrogen phosphate anions are exchanged for hydroxide ions.
Dilution Effect on the Investigation of Soil Organic Matter Quality in UV-VIS Spectra
Soil organic matter is a factor in many areas. Its knowledge helps to develop more accurate models and to use more effective predictions and estimates. While the quantity of organic matter can be well characterised, determining soil organic matter quality is a major challenge. Several methods (mainly based on spectral analysis of organic matter extracts) have been developed, such as the E4/6 [465/665 nm] or E2/3 [250/365 nm] ratios. The ultraviolet and visible light (UV-VIS) spectra of the extracts (200-900 nm) form exponential curves, from which the ratio derived from the data measured at selected points provides information on the molecular size distribution of the organic matter (ratio of humic acids to fulvic acids). The conventional E4/6 values generally give good results for the qualitative distribution of organic matter. If the samples contain some interfering factor, conventional calculations based on the ratio of the two points can be problematic. However, our EFA (Exponential Fitting Approach) method gives much more reliable and repeatable results by fitting hundreds of points. EFA is less sensitive to dilution differences in samples, which has proven to be more reliable (or at least as good) than the conventional method. Therefore, its use can improve the accuracy and repeatability of organic matter quality determination.
The Shortening of Sustainable Supply Chains in Hungary and Europe
The study examines the impact of supply disruptions arising from the COVID-19 pandemic and the energy security challenges primarily resulting from the Russian-Ukrainian war on the re-evaluation of sustainability considerations and the European green transition, especially regarding the potential strategic importance of renewable energy sources. The justification for the shortening of the long supply chains can be argued from the perspectives of supply security and sustainability. Furthermore, the economic validation of sustainability considerations is receiving increasing attention in professional discourse, sparking public debate. One of the primary tensions underlying these polemics is the conflict between short-term economic interests and long-term sustainability and environmental considerations. These interests often contradict each other, and the ongoing professional debate surrounding the shortening of supply chains provides relevant insight into these conflicts. However, the supply disruptions resulting from COVID-19 have re-emphasized the importance of supply security, prompting many economic actors to reconsider their supply strategies. The growing significance of supply security is evident in surveys, expert analyses, and economic strategic documents. The energy challenges posed by the Russian-Ukrainian war have, in turn, prompted EU policymakers to reform the energy strategy. The risks associated with energy security highlighted the vulnerabilities stemming from dependency on external fossil-based energy sources. This article aims to answer the question of how short-term economic interests and longer-term sustainability goals can be reconciled in light of the supply disruptions experienced during COVID-19 and the Russian-Ukrainian war. It does this through a literature review of professional debates and relevant expert analyses, strategic EU documents, and by examining key indicators of the EU's energy dependence. The restructuring of the EU's energy policy demonstrates the feasibility of rapidly implementing major transformations in complex systems when necessary. Beyond facilitating professional discourse, the experiences from these events can also boost the European green transition, as a green Europe built on its renewable resources can be more resilient against challenges of the future. This is in line with both economic and environmental objectives. The main conclusion of the research is that the EU's successful transition to renewable energy sources, in addition to achieving environmental goals, can contribute to reducing external risks through the alleviation of energy dependence. Furthermore, energy security provided by its own energy sources facilitates the growth of the real economy and underpins the EU's geopolitical position.