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Creating forest curtains on sandy or highly compacted lands affected by desertification necessitates precise control, given the challenges associated with the soil management in these regions. The mechanisms designed for planting forest seedlings face significant challenges: the working apparatus responsible for handling seedlings during planting can inflict notable damage to the stems, particularly through scratching or crushing. This issue usually arises from the design solution and the shape of the mechanical organ handling the seedlings. Moreover, it is highly important to improve the control over the seedling positioning in the soil, action that often encounters issues such as inadequate planting depth or improper planting angles. The present research evaluates a novel modular planting system, which can have excellent effects for areas with difficult or desertified lands. The objective was to obtain a precise control over seedling planting, by enabling the mechanism to automatically adjust its grip and force according to root dimensions, stem characteristics, and seedling size. This ensures effective protection of the seedlings and enhances the overall planting process. The mechanism demonstrated excellent performance and successful adaptation to challenging sandy terrain conditions. The proposed solution offers several technical advantages, including: the precise adjustment of the clamping force on the sapling during planting, based on the condition and size of the woody stem and a better adjustable spacing between the gripping jaws. [ABSTRACT FROM AUTHOR]

Adequate nutrition practices are essential for the efficient production of superior goods in aquaculture systems. Nutrition is a key component in the aquaculture industry because feed constitutes about 50% of the variable expense of production. Fishmeal and fish oil have traditionally been the main primary materials used to support the aquaculture industry. They have largely been supplanted by plant-based raw materials, but specific techniques are needed to satisfy fish dietary needs. As aquaculture has expanded, people have been searching for alternative farming nutritional sources since fish meal and fish oil are produced from captured wild fish. Fish have different nutritional needs that rely on a variety of variables. This paper describes an experimental study that was completed on the production of pelletized complex feeds with high stability that were used in the feeding technology of some fish species grown in a polyculture system with recirculation and cyclic water supply. The purpose of feed formulation is to mix ingredients of different nutritional quality so as to obtain a balanced diet, which biologically available nutrient profile approximates the nutritional needs of the concerned species. In fish farms, the choice of feeder for different types of fish takes into account the following criteria: the level of stability in the water, the return on investment in feed, efficient conversion of feed and its attractiveness to fish. The high level of feed stability prevents feed losses and reduces water contamination. The results showed a high stability of the pellets associated with an important increase in the size of the fish raised in the polyculture system. Although each feeding recipe showed benefits for certain fish species, the R3 feeder was the optimal mix, leading to 43% average growth for all varieties and being considered the best option for polyculture systems. [ABSTRACT FROM AUTHOR]

The global need for food is increasing every year, yet aquaculture production in most countries has stagnated or increased relatively slowly in the last decade. The primary goal is to increase annual production using sustainable aquaculture, delivering many social, economic, and environmental long - term benefits. Closed fishfarming systems are attractive solutions for intensive production, because they can provide favorable development conditions and allow a strong input and output control, avoiding damaging the ecosystems and wild populations. The current study includes a series of experimental investigations related to intensive growth of cyprinids in polyculture system, employing various renewable energy sources in order to provide the daily energy requirement. The research was carried in a high-capacity impermeable concrete pond, covered with a presocratic PVC membrane, equipped with an automatic system for regulating oxygen and food. The energy independence of the fish pool is ensured by a hybrid photovoltaic-wind turbine-diesel system, which helps the optimal growth of fish by maintaining a high-quality of water. Water quality characteristics must be accurate and reliable evaluated in order to ensure a successful and sustainable aquaculture business, using environmentally friendly methods. Without a comprehensive understanding of growth circumstances, fish health may suffer, and incorrect feeding practices may be employed, resulting in unsatisfactory output levels, high input costs, water contamination, and even diseases. The composition of the water from the fishing pond (dissolved oxygen, pH, turbidity, EC, salts, dissolved solids, nitrates, and so on) had been determined weekly during the tests carried out over a one-year growth cycle. At the same time, the health and development of the fish material were being monitored. Our aim was to analyze different nutrition recipes in order to increase productivity in intensive aquaculture systems. The proposed diet showed very good results, especially for the growth of Cyprinus carpio Linnaeus. Due to the pond covering system, which better preserves the interior heat and provides a more pronounced thermal inertia, all fish species have seen constant growth, even throughout the colder months. [ABSTRACT FROM AUTHOR]

Jerusalem Artichoke (Helianthus tuberosus L.) is a technical plant that manages to adapt very well to unfriendly environments, even in polluted or poor in nutrients soils and may serve in the near future as an important raw material for the food, chemical, and pharmaceutical industries. Furthermore, the plant is growing rapidly, producing large amounts of biomass and offers the possibility to be harvested up to 2 times a year, therefore presents a high potential to be used in the field of biofuel production. The plant's capacity to multiply easily by developing small tubers in the soil, allowing the production of economically advantageous crops, can be considered an advantage for biofuel producers, however this feature might be a drawback for agricultural land owners considering the very invasive behavior. The present paper aim to assess two Jerusalem Artichokes crops established on marginal soils, assessing productivity and the extensive impact on the ecosystem, paying a special attention to plant invasiveness tendencies. [ABSTRACT FROM AUTHOR]

The challenges we face today envisaging environmental protection, starting from global warming and climate change, up to natural resources depletion, creates opportunities for developing new technologies for biofuel production. Considering that most biofuels used at the moment are based on energy-intensive crops, the question arises whether occupying large areas of land to the detriment of food is justified or not, especially as these crops generally deplete the soil of nutrients. In the present paper we propose a different approach for assessing an easily adaptable energy plant named Sweet Sorghum, that can grow with low input requirements, in difficult growing conditions, on contaminated or poor-nutrient and dry soils, and yet having a high productivity potential. Our research directions are targeted towards identifying the best opportunities for producing bioethanol from Sweet sorghum testing different varieties and sustainable planting conditions. We have been established several experimental cultures and evaluated the potential for producing biofuels using different techniques, such as juice extraction and fermentation and lignocellulose processing. [ABSTRACT FROM AUTHOR]

The off-grid hybrid energy systems have become a viable sustainable alternative for supplying with energy isolated autonomous farms, being more reliable options, since they have more than one electricity generation sources. This article addresses the challenges related to the configuration of a hybrid energy system composed of a wind turbine, photovoltaic panels, a diesel generator and rechargeable battery storage, which is associated with an autonomous off grid fishing pond. The first step in designing predictive control was to define consumers, their particularities in operation, and their energy demand model, then to estimate the real potential of producing renewable energy depending on the location and to create consumption models that maximize the use of power from renewable resources. A consumption management strategy has been developed for an autonomous and automatic fish pond management system, identifying optimal energy requirements for the proper operation of the needed equipment. In order to operate as much as possible using the regenerative energy resources, a prioritizing energy consumption pyramid was designed and tested and a more efficient technique of allocating energy within 24 hours of operation was defined. [ABSTRACT FROM AUTHOR]

The use of antibiotics in large quantities against the combat of pests in soils, indicates an increased remanence of them, which leads to major environmental risks. After entering in the soil, antibiotics are subjected to a succession of biogeochemical processes under the action of multiple environmental factors: absorption, migration, transformation, degradation or nutritional prosperity of plants. In order to know the current state of the environment and the effects of antibiotics it is essential to discover procedures for improving the degradation and combating the dissemination of antibiotic resistance. Research in recent years on the extraction of antibiotics from the soil is based on complex processes, such as: Soxhlet extraction, ultrasonic extraction or accelerated solvent extraction. Soil residue was determined using liquid chromatography coupled with mass spectrometry, being the equipment that provides the highest accuracy in the analysis of polar compounds in very low concentrations. The purpose of the paper is to find an efficient and ecological solution for the elimination of antibiotics from soils and to highlight the evaluation of the contaminated land regarding the antibiotic residues and the impact on the composition of the bacterial community. Information about the effects of antibiotics accumulated in soil, persistence, resistance and sensitivity to chemical and microbiological substances, degradation and results related to soil fertility and crop production are highlighted. [ABSTRACT FROM AUTHOR]

Large areas of soil are historically contaminated with petroleum hydrocarbons, mainly due to lack of environmental protection legislation and careless oil extraction in the past. In some cases, one of the potential remedial actions may be the bioremediation of the oil contaminated soil, due to low cost and low environmental impact. The focus of this research paper was to analyze the efficiency of the ex-situ bioremediation of oil contaminated soil at a large scale, in the open air. The investigations were performed by an ex-situ method in a bioremediation plant with a large capacity. Experiments were conducted both in open air (large scale, less controlled environment) and in the laboratory (small scale, controlled environment). Aeration of the contaminated soil was done using a windrow turner that also had a sprinkler system mounted on it for humidity control. Laboratory analysis was conducted at the beginning to check the availability of petroleum degrading indigenous organisms in soil. The hydrocarbons degrading speed was higher in the field trials under laboratory conditions, but only in the first phase. The experiments showed up that the overall remediation speed in a longer period of time tends to be equal in laboratory and in uncontrolled environment. [ABSTRACT FROM AUTHOR]

The aim of the present paper was to illustrate certain methods and the associated experimental procedures for determining the main defining characteristics of rechargeable batteries that may be used for powering various autonomous sensing devices and also a selection method/criterion to determine the most suitable rechargeable battery to be used in conjunction with the autonomous power supplies. During the rechargeable batteries evaluation process one has also considered the main characteristics of an autonomous system related to the charging and discharging procedure, while the monitoring was carried out using a dedicated software. [ABSTRACT FROM AUTHOR]

The paper is a review of the current situation of waste management in Romania, focusing on solids recovery and recycling. Although some efforts have been made in the Romanian waste sector in order to reach the European targets within the deadlines, the national waste management plan update and waste prevention program implementation are delayed. At the moment, public awareness campaigns are being developed and implemented for recycling, without much emphasis on reduction. However, for now most of the waste ends up in landfills. The current recycling percentages are below 15% of the total municipal solid waste generated, with the lowest landfilling percentage of 69% (based on Eurostat data for 2011-2015). For 2015, Romania had the highest landfilling rate, of 72%, compared to the European Union value of 25.6%. Several separate collection strategies were studied in order to underline the main drawbacks in each case and to identify the optimal options for the given social and economic environment. Solutions for separate collection and waste recycling are being currently implemented in several Romanian regions as case studies under the initiative of local authorities and/or NGO's, without a unitary national approach. The solutions with innovative character and the best practices related to high recovery rates are presented. [ABSTRACT FROM AUTHOR]

The production and use of biohumus is addressed to farmers who own livestock farms, and also to those who have vegetable farms: vegetables, orchards, greenhouses, wineries, etc. and have access to animal manure from other livestock farms. Composting is biological decomposition of biodegradable solid waste under controlled conditions in a state that is sufficiently stable to allow trouble-free storage and handling and that is satisfactorily matured for safe use in agriculture. Biohumus (earthworm compost) or earthworm is a pure natural microbiological organic fertilizer, having no preservatives in its composition, resulting from a mixture of manure and biological waste produced by earthworms. Due to its special composition (it has a large proportion of all the elements that plants need), it can be used in many fields of activity: horticulture, forestry, vegetable growing. When mineral fertilizers are not available or are too expensive, compost is the most important source of plant nutrients and soil condition. The use of the biohumus loosening plant aims to adjust the natural decomposition process, ensure good conditions for the composting process, especially air (oxygen), water, and a good composition of the material introduced into the piles, and monitor them for getting a quality product. Obtaining quality biohumus requires the application of a technology that establishes all the necessary steps to be completed. In this sense, within INMA, two installations necessary in the process of obtaining biohumus were substantiated, designed and realized: the biohumus loosening plant and the IPB biohumus production plant (vermicompost). This paper will present the results of the experiments performed with technical equipment for obtaining biohumus: the IAB biohumus loosening plant and the IPB biohumus production plant. [ABSTRACT FROM AUTHOR]

A directional response for a partially filled tank with agro-food liquids incorporates the motion of the free surface due to roll and longitudinal accelerations into the dynamic tank model. This paper presents an analysis of efficaciousness of different designs of baffles for two different tank, to limit the impact of the response given by the liquid on the tank walls. In this paper modelling of the behaviour of the cross-section circular and ellipsoidal tank with baffles, partially filled with liquids agro-food, was developed, which performs a braking-in-a-turn manoeuver. Two different tank truck models have been used to simulate the sloshing effect of agro-food liquid cargo. Is also studied the two geometric models of the tank was done by using SolidWorks and simulating the behaviour of the tank ANSYS-CFX. In this study, there were simulated and modeled two models of tank-type "X", respectively type "Y" used for the storage and transport of liquid agro-food products, namely water, for different speeds (v = 14m / s and v = 20m / s) and two filling levels of the tank trucks (40% and 80%). The results obtained were compared the behaviour of the tank partially filled into a braking-in-a-turn manoeuver, in which the total values of the deformations that appear as a result of the impact due to the movement of the liquid inside the tank trucks. [ABSTRACT FROM AUTHOR]

Ozonation process analysis involves the development of mathematical models. Modeling is the action that reflects a phenomenon which is inaccessible to direct research by using a model elaborated in conditions and means that can guarantee the validity of the results. In the presented study two simulation programs were developed Mathlab Simulink in order to determine the substrate constant consumption and the reaction order. For evaluating the mass transfer and ozone consumption a hydrodynamic model based on the equation of ozone dispersion in water was elaborated using the software package FlexPDE. In the first stage of mathematical model and numerical simulations it was difficult to specify the values of the coefficients entering the dispersion equation, so a series of experiments were conducted in order to calibrate the constants in the equations. The process parameters for the experimental research were: ozone inflow = 5 g/h; wastewater retention time in the ozonation column = 5-80 min, dictated by the provided ozone flow; wastewater inflow = 0.1 -1.6 liters/s. In order to simulate the time variation of the pollutant concentration a Simulink model was designed using library blocks; the parameter values for each block were set according to the corresponding values in the experimental installation. The model analysis was performed by simulation using the Simulink menu bar and viewing the system behavior was realized through the "Scope" window. The time variation of the pollutant concentration was observed in the same time interval as the one in the experiments. Several simulation cases were elaborated based on the ozone dispersion equation to determine the mass transfer coefficient and ozone consumption, considering different orders of reaction n so as to achieve experimentally measured residual ozone values in the ozonation column. For each of the six experimental variants and simulations performed k values were obtained. [ABSTRACT FROM AUTHOR]