Browse

Natural zeolites, a family of hydrated aluminosilicates, are important raw materials for micro and nano technologies due to their molecular-sieve, ion-exchange and catalytic properties. Their porous crystalline framework is built from alternating SiO4 and AlO4 - tetrahedra forming cages and channels, and improvement of zeolite performance is possible by thermal and chemical treatment. The influence of hydrochloric acid and calcination on heulandite-containing tuff from the Georgian Dzegvi-Tedzami deposit was studi...

Historical pollution with hexachlorocyclohexane (HCH) isomers of soil and groundwater unfortunately is an unsolved problem, especially in some countries where Lindane is still produced, as also in Europe in the surrounding areas of former production sites or landfilling sites usually due to inadequate long-term storage, treatment or recovery of these wastes. HCH removal technologies are usually dedicated to soil remediation, leachate treatment, water and wastewater treatment. This paper presents the research effor...

Bregovo is a small Bulgarian town located on the border with the Republic of Serbia. It is situated 6 kilometers from the mouth of the Timok River, which flows into the Danube River. Despite the proximity of the river, the town experienced some complications in its water supply. The purpose of the research is to to analyze and evaluate the water supply system of the town of Bregovo. The water supply in the municipality of Bregovo is taken care of by the operator "ViK Vidin" EOOD. The separate territory of "ViK Vid...

Firstly, this paper is focused on the analysis of runoff and erosion conditions in the chosen locality, which is in the South Moravian Region of the Czech Republic. The analysis was made using geographic information systems, mainly the ArcGIS Pro software program. Water erosion endangers more than fifty percent of arable land in the Czech Republic. Unfortunately, there is no systematic protection of the majority of soil erosion-threatened areas that would prevent further losses. One of the main causes of this is t...

Changing climatic conditions in urbanized areas enormously impact the quality of life in urbanized areas. Persistent prolonged dry periods, extreme downpours with heavy heaviness or prolonged rainfall are an extreme problem for effective water management in cities. Extreme weather changes also risk the environment when infiltrating or relieving highly contaminated water from the first run-off. These wastewaters are a potential source of groundwater and surface water pollution in which various pollutants are concen...

Since ancient times, mankind has tried to establish a causality of the phenomena that occur in the surrounding world, to find solutions and answers. Floods are widespread in the Danube Delta they cause great material damage and loss of human life and important consequences. The production of floods in the Danube Delta is due to the entry into the Danube of large amounts of water from rains, from the sudden melting of snow and mountain glaciers, as well as from underground water sheets. Deforestation favors the rap...

Climate factors are already exerting negative pressure on water resources, society and ecosystems. The analysis of trends and identification of vulnerable water supply areas is related to the River Basin Management Plans. For this end, a methodology for assessment of water resources vulnerability, developed in international projects of the National Institute of Meteorology and Hydrology (NIMH), is adapted. The methodology is further developed by drought risk assessment. The main stages are: 1) Assessment of the cl...

Scientific research using advanced observation technologies and mathematical models aimed at estimating seasonal snow cover and its water equivalent (SWE) helps to reduce the costs of snow cover monitoring and improve the management of the soil-water-crop system. Following the above goals, this paper analyzes two approaches - the Community Land Model (CLM) producing own calculated data, and the ESA GlobSnow v.3.0 product based on the European Space Agency (ESA) GlobSnow project satellite data. The studies were car...

The paper deals with the possibility of applying game theory in the decision of the dispatcher regarding the opening of the gates to the floodplain (construction of flood control measures). When the forecast of the flood course is bur ended with a random error from the normalized normal distribution N (0.1). The forecast itself is in the range of flows are capable of causing significant damage. The experiment tested different options for adjusting the probability of betrayal (error) of the forecast model. The prob...

The results of many research projects and studies report that landuse/ landcover change (LULCC) is a major driver of the changes in the hydrological processes within a watershed. Landuse induced landcover changes, e.g., urbanization, deforestation, have a direct impact on the hydrological regime of watersheds thus increasing their vulnerability to extreme hydrological events. In this research the Soil and Water Assessment Tool (SWAT) was used to study the landuse/landcover change impact on the hydrological dynamic...

The article analyzes and evaluates the current status of the water quality of the Chepinska River. It is one of the main right-hand tributaries of the Maritsa River, and large settlements are located in its catchment area and active agricultural activity is carried out. They cause a strong anthropogenic impact and a significant change in water quality. The heterogeneous impact requires the assessment to be carried out by using a complex of indices that includes the Canadian Water Quality Index (CCME WQI), the Bava...

Due to the historical development of individual regions in Slovakia, there are still areas without access to public water networks. The main reason is the challenging and uneconomical construction of public networks in scattered rural settlements. The small wastewater treatment plants have gained popularity in rural areas of the Slovak Republic. The increasing adoption of decentralized wastewater management is a result of the scattered layout of numerous rural settlements, presenting economic challenges, technical...

Lake Brates is located near Galati city, in the south-eastern part of Romania being one of the largest lakes in the country. Unfortunately, water quality has greatly decreased in recent years, both due to human actions and to climate change. The present paper aims at establishing the quality of the water in Lake Brates as resulted from the calculation of the water quality index (WQI) by the weighted arithmetic method. In order to calculate this index, several sampling campaigns were carried out in various points o...

Flash floods occur in small areas and in a short time after an extreme precipitation event - generally less than six hours. The intensity of the precipitation, the location and distribution of the precipitation, the land use and topography, soil type, etc. determine just how quickly Flash Flooding can occur. These types of floods are extremely dangerous and it is very important to pay special attention to their forecasting. Due to the complex nature of flash floods, in addition to the qualification and experience ...

Arid and semi-arid regions, including Cyprus, are increasingly experiencing severe weather events due to climate change. These events, characterized by prolonged droughts and flash floods, pose significant challenges to the environment, economy, and societal well-being. This paper aims to analyze the challenges of Flood Risk Management (FRM) in dry areas, focusing on Cyprus as a case study. It reviews historical data on temperature and rainfall patterns, flood types, and severity to propose effective, nature-based...

Flash floods represent one of the most significant natural hazards in headwater catchments facing the lack of systematic hydrological monitoring. This study focus on the detection of flash floods on growth disturbances detected at trees of European beech (Fagus sylvatica L.) located in the torrential channel of the Holubi Potok stream in the Jizera Mountains (North Bohemia, Czech Republic). At the injured stems, flood scars were identified and core samples dated by tree ring analysis; the intensity of the disturba...

Estimation of floods is of extreme importance in designing hydraulic structures and systems, as well as in flood management, including ecosystem recovery. Accurate derivation of flood hydrographs in ungauged basins has additional challenges. The aim of this paper is to estimate flood hydrographs with different return periods using a semidistributed hydrological model, in the ungauged River basin of Benca, Albania. Benca River is part of Vjosa River, which is considered the last wild river of Europe. A frequency an...

The results of the study of the dynamics of changes in the territory of the Kakhovka reservoir before and after the explosion of the dam on June 6, 2023 are presented. This led to the destruction of the Kakhovka reservoir and the sharp flooding of significant areas downstream of the Dnieper River, including the delta. The analysis was carried out on two indicators: the water surface area and the water level. As a result of the analysis of space images, it was found that the area of the Kakhovka reservoir decreased...

The present work is the first case where the adsorptive removal of the most commonly used antibiotic - azithromycin from aqueous solution as a model of wastewater treatment plant effluent by acid-modified natural zeolite - clinoptilolite has been investigated. The adsorption processes were carried out under static and dynamic conditions. The acid-modified form of the above-mentioned natural zeolite were obtained with hydrothermal treatment by using 2M hydrochloric acid solution. In order to investigate the adsorpt...

Nymphoides peltata is a typical representative of higher aquatic plants. Despite its wide geographical distribution, N. peltata is a rather rare species. The development of effective measures to protect a species in any territory is possible only if there is complete information on the status of its populations. Study of the size and morphological structure of plants plays an important role in the system of population studies. The purpose of this publication is to characterise the dimensional values of N. peltata ...

Today, more than in the past, water is considered a very valuable resource. Efforts to use it efficiently are growing. One method of using water efficiently is wastewater treatment. Well-treated water minimises negative impacts after discharge into a watercourse, i.e., within or adjacent to aquatic ecosystems, or can be reused, for example, in the form of drinking water. This study focuses on the possibility of treating food industry water using biochar as a sorption medium. Biochar from wood pulp (100%) was used ...

Floods are one of the most devastating natural disasters that can lead to significant economic and environmental damage and even loss of lives. Flood hazard mapping is one of the measures of disaster risk reduction and becoming a more important function in conserving biological diversity and protected areas now and future. Most of the research is focused on determining flood risk in urbanized areas. In this paper, the protected areas affected by potential floods are studied. Protected areas are according to a dire...

The former mining of rock and potassium salt deposits in Transcarpathia and Nearcarpathia (western Ukraine) has a potential impact on water resources and the transboundary spread of saline pollution (e.g. Solotvyno rock salt deposit on the banks of the Tisza River on the Ukraine-Romania border; Kalush-Golyn potassium-magnesium salt deposit in the Dniester River basin). The threat of pollution spreading increases during floods, flash floods, and flooding. The aim of the study is to determine the extent of possible ...

The article includes the results obtained in the growth experiments during the postembryonic development period of the North American sturgeon species Polyodon spathula. The experiments took place in the years 2020 and 2021. Sturgeon larvae aged 5 days old, obtained through artificial reproduction at SCDP Nucet, were stocked and raised until the age of 35 days in two variants, in concrete tanks (useful volume -120 m3 /tank), located in the pilot station intended for fish culture experiments from the SCDP Nucet gen...

Water transport in icy environments necessitates specialized infrastructure to facilitate safe and efficient movement. Ice piers, vital components in these regions, serve as critical pathways over frozen water bodies, enabling the traversal of ships and vessels. This overview encapsulates the scientific exploration of ice piers, focusing on their design, construction, functionality, and the advancements revolutionizing water transport in challenging icy terrains. The design of ice piers requires a holistic approac...

Water transport in icy conditions presents intricate challenges that significantly impact navigability, safety, and operational efficiency. This article delves into the complexities of navigating icy waters, focusing on the diverse forms and compositions of ice that pose formidable obstacles to maritime operations. Pack ice, icebergs, and frazil ice represent distinct challenges, restricting access, threatening safety, and impeding the fluidity of water transport routes. The challenges for water transport in icy c...

Water and sediments in coastal areas interact at different scales, thus shaping the marine environment and providing physical habitat for ecosystems. Hence, the hydromorphological conditions represent a key aspect of aquatic ecosystems considered in the Water Framework Directive as supporting quality elements (alongside the physicochemical), which are expected to provide the boundary conditions for the biological quality elements. Any alteration in those can reshape the corresponding biological conditions at vario...

Since putting in operation of Chernomorets fishing port (Sozopol municipality, southern Bulgarian Black Sea coast) in January 2016, a number of negative effects have been observed in the area. The disturbance in the existing hydrodynamic balance led to intense coastal erosion and unwanted sand accumulation in the wave shadow area. Additionally, the coastal water quality has deteriorated in the port area. In order to undertake measures to mitigate the observed adverse effects, it is necessary to assess in detail th...

Russia's armed aggression against Ukraine has had a catastrophic impact on the natural environment, with hydrology and water resources being among the most vulnerable. The explosion of the Kakhovka hydroelectric power plant dam on 6 June 2023 and the rapid discharge of more than 18 cubic kilometres of water caused an environmental disaster with flooding of large areas, huge human, environmental, economic losses, environmental pollution, significant changes in the hydrology, hydrogeological conditions, activation o...

The present material demonstrates appliance of regional studies on the area of Central Danube Plain in Bulgaria for determination the characteristic maximum flows at nonobserved river sections with focusing on for flood risk areas. River flow is characterized by annual variability in maximum runoff caused by climatic factors and anthropogenic impacts. For this reason, in most cases, information from hydrometric stations cannot be used directly. One of the main tasks of hydrological research is the transfer of info...

Anthropogenic eutrophication is the main ecological problem of the Baltic Sea. However, there are many rivers entering the sea without monitoring points. The paper presents methodology for evaluation of the total phosphorus and nitrogen discharges outflow unit discharges from catchment areas of such rivers. As example, we consider Russian part of the Finnish Gulf catchment area. The first stage of the methodology consists in determination of partial catchment areas of rivers with water runoff and the biogenic elem...

Changing climatic conditions in urbanized areas have an enormous impact on the quality of life in urbanized areas. Persistent long-term dry periods, extreme downpours with large quantities or long-lasting rains are an extreme problem for efficient water management in cities. Extreme changes in the weather also result in a risk to the environment when soaking in or relieving highly contaminated water from the first flush. These wastewaters are a potential source of groundwater and surface water pollution, in which ...

Grasslands is globally important vegetation type for providing feed resources for grazing animals. An improved understanding of the factors affecting the long-term productivity of the ecosystems will be beneficial, as well as to developing a better understanding of the role these ecosystems play in global environmental change. Arid and semi-arid Mediterranean grasslands provide valuable forage for grazing animals in the eastern part of the Mediterranean area and have been subjected to long-term unsustainable grazi...

Climate change brings a number of risks. Increasing numbers of weather fluctuations, floods, extreme heat and droughts have potential to endanger people's lives, health and property. The paper presents modern technologies and possible use in the field of hydrology connected to disaster management. Main attention is paid to the use of innovative technologies for the needs of protecting and prevent population from hydrological risks. Currently, the trend of introducing new technologies is clear, due to adapting to t...

Adaptation strategies are highly desirable documents based on more frequently occurring hydrological extremes. These strategic documents are prepared at different levels, the state level on one side and the regional or city level on the other side. The complex approach that was chosen for the Pardubice and Pilsen regions was also applied to the territory of the Dyje basin. Specifically, a multi-criteria analysis was used as a means of selecting priority model areas. Based on the analyses developed from the availab...

Accurate river flow forecasting is an extremely important issue for proper management and optimal use of water resources as well as for warnings of extreme hydrometeorological events. Rainfall-runoff simulation is essential for short and longterm forecasting of the river discharge. Determining the relationship between rainfall and runoff is one of the most important tasks faced by hydrologists. This relationship is a nonlinear and extremely complex process influenced by many factors such as watershed topology, veg...

The study presents results and discuss statistical properties of wind-generated sea waves measured in transitional waters of the Burgas Bay at the Bulgarian Black Sea. Wave measurements were acquired by Acoustic Doppler Current Profiler at two locations offshore Kraymorie and Chernomorets at water depths of approx. 15 m and 18 m, respectively. At each location, data were recorded for about three and a half months in winter seasons of 2021-2022 in front of Chernomorets and in 2022-2023 offshore Kraymorie, when stor...

The article presents the results of population studies conducted in the floodplain of the Seim River within Sumy region, Ukraine. The ontogenetic and vitality structures populations of Potentilla erecta and Althaea officinalis. During the study, the following methods were used: the geobotanical method, morphometric analysis, complex vitality analysis. In general, for the region of research on P. erect- priority is the introduction of active protection measures aimed at increasing the distribution centers and the f...

Precipitation is the main source of recharge of water resources, thus guaranteeing their renewability. Not only hydrometeorological changes, but also anthropogenic factors exacerbate the above-mentioned effects. The increase in the level of investment seen especially in recent years in urban agglomerations through the intensification of development, increased development of impervious and paved surfaces, the use of vacant land, and thus the reduction of biologically active areas has resulted in an increase in rain...

The Danube Delta is a wetland of global importance, providing several ecosystem services. The sustainable development (i.e., economic, social and environmental) in the area depends on the health, quality and quantity of the natural resources. Water is one of the most important resources. Largely, the Danube Delta, which receives the input of water and sediment flux from the Danube River, gathered form its entire basin, may experiences lower water quality due to natural and anthropogenic factors, from basin to loca...

In recent decades, small domestic wastewater treatment plants have become popular in rural areas of the Slovak Republic. The reason for the expansion of decentralized wastewater management is that many rural areas have scattered settlements, and a centralized wastewater disposal system is economically, technically demanding, and inefficient. The disadvantage of using small domestic treatment plants in terms of environmental protection is that these facilities have yet to be significantly monitored. Due to improper...

Knowledge of the coastal hydrodynamics, in particular the storm induced waves, is essential for management of the extremely vulnerable coastal environment. There, wave processes dominate surge, coastal currents, sediment transport and species distribution. Therefore, it is important to have a detailed insight into the exposure of different coastal areas to wave action. The study proposes a wave exposure classification of the Bulgarian Black Sea coast according to wave climate conditions as required by the Water Fr...

Water resource of a given river basin is the main component of the ecosystem and water resources management system as well. Ecological flows are considered within the context of the Water Framework Directive (WFD) as -a hydrological regime consistent with the achievement of the environmental objectives of the WFD in natural surface water bodies as mentioned in Article 4(1). The so-called Heavily Modified Water Bodies (HMWB) or -regulated rivers- have modified flow, which is influenced by reservoir compensation rel...

The study is focused on statistical analysis of river discharges. The registered river flow regime and hydrological characteristics of Yantra River are investigated. Yantra watershed is situated in North Bulgaria and belongs to Danube river basin Directorate. The current study is focused on the low flows. Thirteen hydrometrics stations located in the watershed are available for the investigation. Data used are from monitoring network of the National institute of meteorology and hydrology, Bulgaria. The flow durati...

Heavy rainfall in the summer have become more frequent, and when they occur over the coastal region, the cumulative hazardous pressure leads to floods, loss of physical life and socio-economic impact. Such is the disaster due to the floods in Tsarevo at the end of summer 2023. The paper contains a conceptual analysis of hydrological and meteorological conditions, land cover and use, and institutional preparedness to deal with dangerous floods. It is prepared on the basis of the data from Copernicus Land Monitoring...

Compliance with EU environmental regulations and directives regarding effluent water quality discharged is seen as the main driver for the development of wastewater treatment technologies. The Water Framework Directive, the UWWT Directive, and the Nitrates Directive require the reduction of eutrophication caused by nitrogen and phosphorus emissions. In Romania, only approx. 54% of the population is connected to centralized sewage and wastewater treatment systems, meaning that approximately 8 million inhabitants ar...

The largest aluminum factory in Eastern Europe is located near Slatina. Before Romania acceded to the EU in 2007, many environmental protection rules were omitted in this area. The paper analyzes the water table pollution along the Olt River for about 15 km. There are considered the tributary flows on the river, the concentration of discharged pollutants, and the pumping regime from the catchment front. It is built at about 500 m from the river, on the left bank, parallel to the river, and consists of 44 wells, of...

Water pollution and climate change are two of the most pressing environmental challenges of our time, and their interconnection is increasingly evident. Water pollution and climate change are interconnected in various ways. The release of greenhouse gases, primarily carbon dioxide, methane, and nitrous oxide, is a significant driver of global warming. These gases contribute to the greenhouse effect, leading to rising global temperatures, which, in turn, affect water resources. Warmer temperatures exacerbate water ...

Among the many factors affecting the average life expectancy and mortality of the population, along with the effective services of the health care system, an important place is occupied by the ecological condition of the environment, in particular, the quality of the security of its resources for human health. Providing the population with safe, clean, drinking water is one of the most important factors in the world and among them in Georgia. According to the data of the World Health Organization, almost 2 billion...

Floods are one of the most devastating hazardous events often causing destruction of infrastructure and loss of lives. In order to mitigate negative flood impact a reliable hydrological forecast is of great importance. Thus using trustworthy information on the meteorological elements that mostly contribute to the occurrence of floods - precipitation and temperatures, is essential. Although the accuracy of the global forecasting models like ECMWF, GFS etc. has improved a lot, still sometimes there are extreme meteo...