International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

To establish the influence of different irrigation and fertilization rates on the quality indicators of the fruit of three specific genotypes of tomatoes- Maldo, Pink Rock, and Hayet- in 2022, experiments were conducted in the experimental field of Maritza Vegetable Crop Research Institute – Plovdiv in an unheated steel and glass greenhouse type Venlo. The experiment was conducted under three irrigation regimes – optimal, reduced, and increased irrigation – 100%, 75%, and 125% using water-saving irrigation technologies and three fertilization regimes – optimal, reduced, and increased fertilization – 100%, 75%, and 150%.
It was found that reducing the water content resulted in a slight increase in dry matter, total soluble solids (TSS), and vitamin C content while varying the fertilizer rate did not significantly change the studied characteristics. Tomato fruit quality was more affected by irrigation than by fertilizer levels. Titratable acidity and pH differed between cultivars but not between treatments applied. The highest dry matter, TSS, and vitamin C contents were observed in the treatments with low irrigation rates and optimal fertilization (75%W and 100%F). Strong positive correlations were found between dry matter, TSS and vitamin C, while a strong negative correlation was found between fruit firmness and dry matter, TSS and vitamin C.
The factor Genotype had the strongest effect on the tomato fruit quality parameters studied, with a weaker but proven effect of the individual factors irrigation rate and fertilization rate on dry matter, soluble solids content, and vitamin C. The highest fruit quality was found in Pink Rock, followed by Maldo. The variety with the lowest values for most of the quality indicators is Hayet.

One of today’s biggest challenges is to manage the extremes in water resource management associated with climate change. Central Europe and Hungary are among the regions most affected by the impacts of water management extremes. The study area is one of the most vulnerable regions of Hungary, with a high climate sensitivity. Although there is a significant network of infrastructure in place to mitigate water shortages, it is both overstretched and burdened by significant operating costs. The recent energy price explosion has focused attention on the operational issues of these systems. However, for areas beyond their reach, only locally available primary and secondary water resources offer the potential for prevention and mitigation. These have a limited reach and are costly to use. One of today’s popular slogans is ‘water to the landscape’, and the paper will discuss the possibilities and limitations of this in the sample area.

A lot of techno-economic analyses have been conducted to seek the most cost-effective solution for irrigation purposes applied in the interval time of 25 years of project life. The possible benefits outlined by the PVWP system implementation have been identified, as well as the effects of the most sensitive parameters, such as installation price, incentives and other credit options such as carbon credit rate or feed in tariff. The output carried out from the simulation shows that PVWP system represents the best solution to provide free carbon and costless electricity to run the water pump for sprinkler irrigation in the agriculture sector in Albania. The environmental benefits have been also addressed, evaluating the CO2 emissions saving achievable from the PVWP system operation and some financial aspects such as simple payback period (SPP), NPV and the carbon footprint reduction per ha. As a conclusion replacement of diesel-powered water pumping used only for irrigation purposes results in an annual net reduction of CO2 emissions by 1.9416 ton per year which is equivalent to 861 litres of gasoline not burned. The net specific GHG reduction results 0.09708 kgCO2/m2, simple payback period results 5.7 year and Net Present Value (NPV) 4961.74€ and by applying a Feed-in tariff 0.0600 €/m³ then the water sale income results 19 817 € for the entire project life of 25 years starting from 2022.

The economic benefits have been also addressed, evaluating the energy production and distribution throughout the year and cost of electricity generation for small PV plants up to 2MW. Renewable energy sources, including solar, wind, hydropower, biofuels and other renewable sources that may be developed in the future are the main focus of the energy transition ensuring a safe step on the path to an intensity system. low energy, with minimal impact of greenhouse gases (GHG) and with a minimal cost for end users. Over the last two years PV systems have attracted a large amount of monetary and investment globally, especially in EU countries. The responsible ministry (MEI) and its subordinate institutions have drafted and approved the “National Strategy of Energy 2018-2030 “, consisting of 6 possible scenarios of energy transition towards a sustainable, reliable and diversified energy system. The national strategy seeks to meet its objectives based on Renewable Energy Sources (RES) and Energy Efficiency (EE). Hence, the economic aspects and identification of the most influenced parameters is identified and highlighted.

A lot of economic analyses have been conducted in the last ten years to establish the most cost-effective solution for irrigation and evaluation of the project profitability. The benefits generated by the PVWP providing water by a submersible pump located inside a deep well have been highlighted for Divjaka region. The solar potential in the site is quite enough to be used to pump water from the deep well into the tank positioned at an effective altitude which can provide the water quantity and pressure by gravity. The study shows that installing a PVWP system represents the best technical and economic solution to drive a water pump that provides water for sprinkler irrigation. The economic benefits have been also addressed, evaluating the energy production and distribution throughout the year and the specific cost per m3 of water supplied (€/m3). Renewables are the key to enhance food and water security, drive agri-food productivity, leading to socioeconomic benefits in recovering from post-Covid-19. By combining our knowledge, data collected, surveys together can contribute to economic growth of our community-ensuring access to clean and affordable energy and raising the standard of living of rural and most vulnerable communities. In the area there are used two types of water pumping for irrigation purposes: Diesel driven water pumps and electricity powered water pumps. Both systems are very costly due to the high fuel cost and on the other hand self-investment to bring electricity from the national distribution lines are needed.

An analysis has been made of the research work to determine the impact of water deficit on the quantity and quality of sunflower production. Studies have also taken into account the more frequent drought in the last decade – soil and atmospheric. Research shows that its good drought resilience allows it to be grown under irrigation conditions, but is sensitive to severe droughts, especially in the critical stages of development which leads to poor quality and drastic decrease in yield, and in some years to the lack of yields. The results show that sunflower irrigation has a large reserve for obtaining additional yield, which has been established through experiments in different parts of the country. The increase in irrigation is about 30-40%, and critical for water stress is the period of 20 days before and 20 days after flowering.

An analysis has been made of the research work to determine the impact of water deficit on the quantity and quality of sunflower production. Studies have also taken into account the more frequent drought in the last decade – soil and atmospheric. Research shows that its good drought resilience allows it to be grown under irrigation conditions, but is sensitive to severe droughts, especially in the critical stages of development which leads to poor quality and drastic decrease in yield, and in some years to the lack of yields. The results show that sunflower irrigation has a large reserve for obtaining additional yield, which has been established through experiments in different parts of the country. The increase in irrigation is about 30-40%, and critical for water stress is the period of 20 days before and 20 days after flowering.

Water is the basic source of life for plants, animals, and humans. However, the impact of climate change drastically reduces its sources. Rational consumption of clean water leads to the need for finding alternative water sources for irrigation of gardens. As an alternative source, greywater can play an important role. Greywater is waste water from households, which does not contain faecal compounds. The aim of this paper to present design concepts of systems for collecting, purifying and application of greywater and well water for irrigation of gardens. The concept is developed using previous own research results, as well as available literature, on the benefits and risks of using greywater, and the effects of purifying greywater and well water through various treatment systems. The paper presents two systems: (1) a system which allows the storage and irrigation using raw greywater and (2) a system where greywater supply is not continuous. The second system is suitable not only for households but also for other facilities, e.g. touristic, recreational and weekend resorts. This system proposes alternate irrigation with grey and well water for resolving two problems: inappropriate greywater quality and inappropriate water quantity. In general, the system reduces the risk of soil degradation and is water saving by automatically adjusting irrigation with regard to the soil moisture content.

The deficit of the irrigation water requires irrigation technologies of more efficient water use. For cucumbers the most suitable is the drip irrigation. For establish the appropriate irrigation schedule of cucumbers under the soil and climate conditions in the village of Chelopechene, near Sofia city, research was conducted with drip irrigation adopting varying irrigation schedules – from fully meeting the daily crops water requirements cucumbers to reduced depths with 20% and 40%. Have been established irrigation schedule, irrigation water productivity and yields of in plastic unheated greenhouses of the Sofia plant.

The working members of the batch-combined machine for minimum tillage and crop tending are combined into two separate batches. By means of the first batch, there are performed simultaneously tilling and sowing operations, but the second is intended for surface tillage and crop tending. During just one field day, the machine is capable of performing 8…10 agricultural operations, and its working members can work in three modes: 1. Soil loosening without furrow slice overturning, when the main tillage unit (wedge) is in its working condition together with lateral knives (for the eroded soils); 2. Clod furrow slice pulverization and mixing, when the main tillage unit (wedge), lateral knives and rotary tiller are in their working conditions (for the non-eroded soils); 3.Cultivation of humid soils with a partial overturning of furrow slice, when the main tillage unit (wedge), lateral knives and rotary plough (instead of tiller) are in their working conditions. The cost of oil and lubricants and operating time are reduced by 2…2,5 times, and besides, the agrotechnical terms reduce considerably. The design formula for tillage output envisages both broken and unbroken soil strips. This formula can be also used for calculation of the machine output during cultivation, sowing, cutting the irrigation channels and so on. The proposed batch-combined machine can be also considered as energy-saving, resource-saving, environmental and advanced technology.

To determine the irrigation water productivity for raspberries during their cultivation in the soil-meteorological conditions of the area of the village of Chelopechene – Sofia, studies have been carried out with drip irrigation of a plantation with the variety "Lyulin". Various regimes have been studied – from full satisfaction of the daily needs of the culture to water, to irrigation with 20% and 40% reduction in irrigation regulations.

The meteorological conditions during the study period determined the number of irrigations and the size of the irrigation and irrigation norms of the culture.

On average, over the survey period, the highest yields were obtained with the watered with 100% irrigation norm option. The increase in yields resulting from the irrigation is about three times the non-irrigated option in surface drip irrigation.

The highest irrigation water productivity of 4.3 kg of raspberries per cubic meter of water is obtained in variants irrigated with a 40% reduced irrigation rate.

A Polish experience with 10 hybrids of sunflower field was made on the Chelopechene Field, Sofia, on cinnamon forest soil. Sunflower hybrids are grown under non-irrigating conditions and under irrigation conditions with drip irrigation and microwaving.

The meteorological conditions during the study period determined the number of irrigations and the size of the irrigation and irrigation norms of the culture.

It has been found that the yields obtained under irrigation conditions are higher than 13 to 46%, with drip irrigation giving better results than sprinkling.

The Maritsa, San Luka and A58xC23 hybrids have been shown to be suitable for growing in non-irrigated conditions, while the hybrids "Vokil", "Michaela" and "Maritsa" hybrids are irrigated.