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Lakes on the Black Sea coast are the direct result of soil erosion and marine or hydrographic accumulations, consequence of the specific evolution of the nearby sea basin. They depend on the variations in groundwater levels, rainfall or other hydraulic surface sources. In recent decades, as a result of many small, local earthquakes, some deep currents have appeared. Lakes as origins, are of fluvial-marine estuary, lagoons or artificial. Many of them are tourist attractions, due to the specific microclimate establi...

Asellus aquaticus Linnaeus, 1758 is the widespread and common Palearctic freshwater isopod, feeding on detritus. This crustacean, probably, has its ancient evolutionary origins around Siberia and has spread from there to Western Europe and North America. Commonly associated with a temperate climate, it has been recorded as far south as the Mediterranean, and as far north as Scandinavia. The species is primarily associated with the b-mesosaprobic waters of the palearctic realm i.e., high concentrations of dissolved...

Gamma-ray spectrometry is one of the most important and informative methods for various geological surveys. In field geophysics on the surface or in the air, the method is used for regional geological zoning, mapping of bedrock outcrops, etc. The most promising direction of geological surveys today is research with the use of UAVs. Conducting gamma-ray spectrometry using UAVs is complicated by the need to accumulate a large number of measurements to construct the correct gamma-ray spectrum. From this point of view...

Landslides and torrential erosion are among the most common geomorphological processes manifesting in the Romanian Subcarpathians, with a very high impact on the territory. The hydrographic basin of the Rau Alb stream, a left tributary of the Dambovita River, located at the western extremity of the Subcarpathians of Curvature, in the Ialomita Subcarpathians, is subject to complex processes of degradation by surface erosion, deep erosion and landslides. The research works for the analysis of morphodynamic processes...

The article provides data on the use of medicinal plants in landscaping of the Steppe zone of Ukraine, special attention is paid to the creation of a rock garden. Medicinal plants have been widely used by man throughout his entire existence. Today, scientists are very interested in this group of plants due to the emergence of a pandemic caused by the deadly COVID-19 virus. It has been established that the phytochemicals of these plants are potential drugs against this virus. When creating a rock garden from herbac...

Current sources of energy used to power motor vehicles are fuels produced on the basis of crude oil (gasoline, diesel oil). In the near future, these fuels must be replaced with other substances with similar properties that enable them to power the engines of motor vehicles. The amount of conventional fuels is limited and with the ever-growing demand for this raw material, implying, among others, price increase, it is necessary to look for alternative fuels - for traditional mixtures. According to the assumptions ...

The variation in time and space of the groundwater level is conditioned by the variation of climatic parameters. In the current context in which climate change is characterized by periods of prolonged drought and the distribution of precipitation is of the rainfall type, with large amounts of precipitation in a very short time, the groundwater level has accentuated periods of consumption to the detriment of accumulation episodes. In a first phase, the high values of the temperature superimposed over the periods wi...

Natural processes and human influences can cause several environmental issues upon urban and rural aquatic systems, especially in deltaic environs. This study was aimed to assess the vertical variation in the physical-chemical and lithological characteristics of core sediments. 14 undisturbed short sediment cores were collected from soft lacustrine sediments in various shallow lakes situated in the Matita-Merhei interdistributary depression, Danube Delta, Romania. Sediment samples were measured for temperature, pH...

The European Plate Observing System (EPOS), is a multidisciplinary, distributed research infrastructure that facilitates the integrated use of data, data products, and facilities from the solid Earth science community in Europe. The EPOS pan-European dimension is corroborated by 25 countries, 5 international organizations, 149 national research organizations and 256 research infrastructures involved in the data and service provision. The legal and governance framework designed during the Preparatory Phase and deve...

The maintenance of ecological, economic and social functions of forest territories is closely connected with competitiveness of forestry. Its assessment permits to take the right decisions for its enhancement and rational use of forest resources. In this regard the purpose of this paper is to present the theoretical and conceptual framework for development of unified methodology for quantitative assessment of competitiveness of forestry companies in Bulgaria. The theoretical framework is based on the existing theo...

processes and stages carried out to achieve imposed performance objectives. The activities involved in the construction process are characterized by their own level of importance and each must comply with the established monitoring and execution plan, respecting the required specifications, especially in the case of concealed works. According to theoretical research, concealed works are those works or construction elements, which, once completed, can be viewed or inspected with the help of special intervention mea...

The scientific interest of evaluating the thermal regime of various areas has come to the fore with a more complete understanding that all major processes inside the Earth are related to thermal events and that all physical properties of rocks, as a basis for observed geophysical phenomena, are more or less dependent on temperature. The characterization of the thermal regime is followed by the basic elements: temperature and geothermal gradient, thermal conductivity and geothermal flow. The quantitative study of g...

Stakeholders and project activities are related to the typical and usually necessary project components of: ideas, financing and implementation. Our aim is to illustrate useful steps in problem analysis, progressing from system characterization (analytical phase) to predictive modeling (synthesis phase). System analysis and multi-criteria evaluation are used to identify alternative scenarios regarding project goals. The model suggests that “public awareness” is best promoted in projects with a more balanced repres...

The tornado phenomenon is getting to more attention in recent years due its unexpectedoccurrence in the areas where it was traditionally extremely rare. The European strongesttornado since 2001 appeared in Southern Morava region, Czech Republic, June 24th 2021.The paper deals with the incidence of tornadoes, the ways of prediction and measurementas well as the protection advices. The believed life cycle and possibilities of themonitoring, forecasting with the current satellite system as well as their limits werein...

The article deals with the issues of domestic tourism. It is proposed to use the ideas of synergetics to assess the development opportunities of the tourism business in three regions of the Arctic zone of the Russian Federation, taking into account their physical, geographical and economic position. Tourism resources, types of tourism and accommodation facilities were discussed, as well as types of recreational activities in these areas. It is shown that the tourism business is an interdisciplinary science, as it ...

The achieving of 17 United Nations Sustainable Development Goals (SDGs) is closely linked to sustainable soil management to provide food, fibre, fuel, to avoid land degradation, to promote land restoration, water regulation, nutrient cycling and to ensure habitat for biodiversity. Organic soils can be a carbon sink or a carbon source depending on land use and land use management. Agricultural production on organic soils is considered as an important source of anthropogenic CO2 and N2O emissions. Long-term plans to...

Study on the trace elements in Haplic Luvisols and trends of their migration have been carried out in the sites localized at altitude of 1200m in the most Southern part of the Rhodope Mountains bordered to Greece. In that region, there are no industrial or mining enterprises so the technogenic pollution is not expectable to be found. Heavy metal concentrations in the mineral soil vary depending on concentration in parent rock. Content of trace elements was determined after acid dissolving (HF+HClO4) and respective...

This study uses GIS for studying the state of forests, affected by diseases or by pests or have other kind of damages. GIS is an effective tool to examine the phytosanitary status of forests based on existing specialized data from forest management plans and data from alerts submitted to online portal of the Executive Forest Agency, Bulgaria. The spatial GIS analysis of the specialized data for a given forest management unit (State Forestry Enterprise "Chirpan", district Stara Zagora, Bulgaria) is the basis for th...

The priorities in the policy of the energy sector of the Republic of Bulgaria after 1989 are in harmony with the requirements of the European directives and market mechanisms. An important aspect is the policy to promote the use of renewable energy sources (RES), which aims to achieve sustainable energy development and improve environmental performance. It is also related to the implementation of the commitments made by the Republic of Bulgaria regarding the United Nations Framework Convention on Climate Change (1...

Over 30% of the Bulgarian Black Sea shoreline is characterized as a depositional type of coast. A significant portion of it represents well-formed sandy beaches and dune fields, falling under the protection of the European ecological network NATURA 2000. The coastal sector of the Lower Kamchia Depression hosts the longest beach-dune system on the Bulgarian Black Sea coast called Kamchia-Shkorpilovtsi beach. The main task of the project "Mapping and monitoring of depositional areas along the Northern Bulgarian Blac...

The spectral characteristics of the ULF waves (1mHz -1Hz) provide useful information about the conditions in the solar wind and in the magnetosphere. A series of geomagnetic field variations data are collected by the tri-axial search-coil instrument and acquisition system located at Panagjuriste, Geomagnetic Observatory (PAG), Bulgaria and other series of data are collected from two different instruments located at Conrad Observatory (WIC), Austria and Ebro Observatory (EBR), Spain, which operate within INTERMAGNE...

In the article synthesis of structures of disperse systems on the basis of gypsum is considered. Such systems are necessary for receiving materials which exclude burning of raw materials on the basis of gypsum waste for the receiving binders. For them use a certain composition of raw mix. Selection of structure of compositions allows to increase properties of materials. Such materials are characterized by high strength. The process of formation of structure of a gypsum which is received by hyper pressing is studie...

In the paperwork are presented aspects regarding uncertainty involved in the process of spark ignition assessment for intrinsically safe equipment. In the first part of the paper was presented the explosion risk. In the field of power generation and also, in a lot of other fields of industrial activities, the occurrence of flammable substances is a common fact. As a consequence, an explosion risk can occur. On the other hand, the installations placed in areas endangered by presence of flammable substances should b...

The case is considered when at the Koknese district in Latvia the hydrogeological situation for dolomite excavation quarries is heterogeneous. The place geological build is complex and the quarries are situated close to large surface water bodies represented by the Daugava river and by the Urgu reservoir. The depression cones of the quarries were obtained by using the local hydrogeological model (HM). The primary data for creating the local HM were provided by the regional HM of Latvia LAMO4. The Groundwater Vista...

Many countries face the growing issue of an ageing population, which can be characterized as one of the most important phenomena of this century. One of the key factors in the elderly’s lives is spatial mobility, which is linked to their quality of life and well-being, including their independence and self-reliance. Walking is understood as an essential activity in this frame. The progressive erosion of physical and mental capabilities in elderly persons is causing growing issues for walking and close-neighbour mo...

The global problems of the functioning of the economy, industry and energy are among the most important areas of scientific interest and knowledge. Renewable energy sources play a significant role in the global energy sector. The potential applications of these sources are almost limitless, which makes it possible to expand the list of energy resources used. With the economic growth of the forest, woodworking and pulp and paper industries, waste from the wood used in processing-bark and branches, wood chips, scrap...

The purpose of this study is a spatial-dynamic and structural hygienic assessment of the impact of the activities of thermal power facilities on the quality of atmospheric air and the formation of potential risks of harm to the health of the population in a large industrial center with a population of more than 350 thousand people and a total area of more than 500 square kilometers. At present, heat and power facilities belong to the main industries and form significant potential risks of harm to public health in ...

The authors substantiate that the implementation of decentralization reform in Ukraine can help to achieve the goals of sustainable development. Procedures and policies for decentralization reform promote socio-economic development of the regions through changes in the country's budget policy. This affects the welfare of the population and is one of the global goals of sustainable development. The main directions of decentralization that directly or indirectly affect the implementation of sustainable development g...

The purpose of the scientific research is the development, improvement and implementation of information technologies for a comprehensive assessment of the intensity and nature of anthropogenic pressure on urban (urbanized) water resources by contact and remote methods to improve the efficiency of the environmental management system and the environmental safety of the water fund of cities. The tasks for conducting research carried out using technologies for remote sensing of the Earth from space (ERS), specialized...

Assessment of the nutritional status of crop stand and other plant biophysical parameters can be a suitable source of information for the application of nitrogen fertilizers in precision agriculture, especially in conditions of high spatial heterogeneity of farm fields. Determination of the application rate of nitrogen fertilizers can be performed based on the plant diagnosis and estimation of plant biophysical parameters, such as nitrogen content, total amount of aboveground biomass and nitrogen uptake (Nupt), or...

The basic requirement placed on any machine system, technology and machine as a whole must be clearly based on the assurance of safe operation and operational reliability, and this is where maintenance is the systematic tool to achieve them. Technical diagnostics is a part of every maintenance and thus becomes one of the decisive maintenance tools in its comprehensive concept. Much attention is now being paid to lignite mining in the Czech Republic, especially when we are talking about the extraction of coal for i...

Currently, there is a serious increase in the use of various e-learning systems. The information technologies of the Learning Management Systems (LMS) platforms should use the possibilities of extracting and analyzing a variety of educational data during learning. Complete and visual learning outcomes are possible through the use of data processing techniques, Educational Data Mining (EDM) methods, and representations in various forms. Comprehensive analysis of data statistics and learning results will ensure high...

In 2011, we developed our application for B-imaging based on binary thresholding algorithm in a selectable Region of Interest. This application has been used in many studies focused on ultrasound B-imaging in neurology; primarily for substantia nigra echogenicity examination and also for some different brain structures, e.g. mediotemporal lobe atrophy investigation. One of principal output value is an echogenicity index which is used as a marker of the echogenicity grade. Many published studies showed that is well...

Soil erosion is one of the most widely dispersed adverse geomorphological processes in a global scale. If it is not limited, it can change the topographic surface, reduce the slope stability and water retention capability, and thus increase the disposition for geomorphological hazards. Heavy rainfalls or intensive snowmelt are the main triggering factors for erosion, but the processes strongly depend on the topography, slope gradient, soil properties, vegetation cover and land use. The aim of the current research ...

In the last years, the cultivation of methane-oxidizing organisms has been sort of great interest, because it allows to obtain value products using accessible raw materials, such as natural gas. The products obtained during the cultivation of mixed culture based on Methylococcus capsulatus can be used in agriculture, medicine and other fields. Nucleic acids and their derivatives are one of the most popular components that can be produced during the comprehensive processing of bacterial biomass. As a result of the ...

Here, we report a laboratory experiment performed with the water from the Don river. Our aim was to examine the effect of NH4VO3 in concentrations of 0.5, 5, 25, and 100 ?g/L of Vanadium (V) on the phytoplankton growth indicators in the absence of their growth limitation by Nitrogen (N) and Phosphorus (P), as well as on the metabolism intensity indicators of plankton communities: biochemical oxygen demand (BOD5) and alkaline phosphatase activity (APA). The stimulating effect on the phytoplankton abundance and biom...

This investigation is aimed to determine the general development phases of the vegetation and climatic situations of the Pur-Taz interfluvial region, Western Siberia (Yamalo-Nenets Autonomous Okrug, Russia) based on the spore-pollen analysis of the bottom sediments of the Lake 17-Ya-01. The palynological analysis was carried out on the basis of 26 samples. In total, 26 palynomorphs have been identified. A spore-pollen diagram, which has been divided on the 4 biostratigraphic sequences (pollen zones PZ I-IV), refle...

The paper examines the influence of vegetation season on canopy height models (CHM) derived from airborne laser scanning (ALS) data. ALS data were captured during the leaf-on (September 2011) and leaf-off seasons (April 2012) on the territory of the University Forest Enterprise of the Technical University in Zvolen, Slovakia. An automated procedures for deriving high-resolution digital terrain models (DTM) and digital surface models (DSM) were developed. CHM was calculated as the difference between DTM and DSM. CH...

The region of southwest Bulgaria is characterized by a large number of fault structures, and the presence of tectonic and seismic activity, thus predetermines the development of dangerous geodynamic processes. This article discusses the estimates of modern movements of the earth's crust obtained from periodic geodetic measurements. They describe the total effect of fast and slow horizontal and vertical movements. Obtaining such estimates, on the order of mm/y, requires determining the coordinates of the points of ...

During the process of drilling wells with a complex spatial profile, it is necessary to obtain timely information about technological processes in order to control them. This issue is relevant for the oil and gas industry, since the number of works of increased complexity is constantly growing. This article discusses the technique of vertical tomography in control problems during directional well drilling. The object of control in this case is the technological equipment, the well and the surrounding soil. The art...

The article deals with the issues of virtual reconstruction of memorable places associated with the life of M.V. Aseev in the Tambov province (Russia). Mikhail Vasilyevich Aseev (1858-1933) was a major Russian landowner, entrepreneur, influential industrialist and philanthropist. In 3D modeling programs (SketchUp, Blender) three-dimensional models of objects (buildings, utensils, etc.) were built according to known parameters (size, material), including both existing objects and lost or partially destroyed ones. U...

The article discusses the visualization of educational information as an approach to the development of a graphic language that exists as a means of communication, in our case, as a language of instruction and research along with the verbal language. One of the means of improving the professional training of future specialists in the conditions of the prevalence of the screen environment is the formation of their skills in visualizing educational information. In the visualization of educational information, great ...

Main pedestrian lines and nodes in urban structures need to be penetrated with water and greenery for the transformation into vital and ecological public spaces. The context of water and greenery provides to public spaces flow of landscape and flow of natural elements through the major arteries and meeting places of the city. Our research on the Danube riverfront in Bratislava and its recreational hinterland focused on implementing greening of the area, the zone in contact with the river, landscape modelling, and ...

The paper investigates the problem of determining the interinfluence of production and injection wells on a single development target. To solve this problem, we develop a stochastic reservoir model, which is a variant of extended Kalman filter. The model is some simplification of the hydrodynamic model. Its purpose is to estimate interwell permeability through production history. We discuss different variants of the model, which vary basing on availability of certain input data. On the baseline, the model can only...

The wind energy is substantially growing in the last decade, but the biggest challenge remains the prediction of the performances of the wind turbines. The increasing energy demand and climate changes forced us to commit quick decisions and to develop efficient solutions. One of the solutions can be repowering and significant changes in transmission systems to deliver it through the electric grid. Fantanele Cogealac is the largest onshore wind farm in Romania. The wind farm exist since 2012, so in at least 10 year...

Zein proteins belong to the class of prolamin proteins which, in maize, represent more than 60% of the total endosperm protein. Based on their molecular weight, sequence and solubility, zeins are classified into four different zein structures (?, ?, ?, ?). The major maize seed storage proteins, zeins, are deficient in lysine and tryptophan content, which contribute to the poor nutritional quality of corn. Therefore, we report here on an original and novel process, which consists in successive grinding and sieving ...

The work describes a method for restoring three-dimensional models of rigid objects from one satellite image, based on the usage of convolutional neural network models. General requirements for reference and test satellite images are: seasonal shooting (lack of snow cover); images? geo-linking to railway infrastructure objects and to the general coordinate projection; presence of image metadata on survey and lighting conditions (geo-reference data and time of survey, photography and position of the Sun); visibilit...

This paper aims to explore the degree of intensification and extensification of agricultural practices followed by farms of different economic sizes and the type of farming in Latvia. While intensification is considered as an effective way of achieving agricultural independence at supra-national and national levels, more voices are raised against an increasing demand for energy and unsustainable agricultural activities causing irreparable damage to natural habitats and reducing biological diversity. Although farmi...

Disasters bring about sudden changes to life, the environment and nature; fundamentally altering landscapes and thus also influencing the history, culture, traditions and environmental perspectives of the regions in which they occur. This study aimed to investigate the ways in which a landscape is treated and changed in the process of recovery from a large scale earthquake and to examine the introduction of green infrastructure during this recovery process. To achieve this, we set two specific research objectives....

The universities in Bulgaria operate in a very dynamic environment. The Ministry of Education and Science (MES) changes annually the requirements that their systems must meet. Changes can be small and affect only parts of the information systems in use or impose fundamental changes. To cope with this challenge, each university has a choice - either to move to a high level of digitalization or to maintain a minimum digitization of processes, so that no correction is needed in them, thus increasing the hours of work...