Violeta Gesovska - Academia.edu (original) (raw)

Papers by Violeta Gesovska

Scientific Journal of Civil Engineering

Environmental Earth Sciences, 2014

ABSTRACT Dojran Lake located in south-eastern part of the Balkan is shared by Macedonia and Greec... more ABSTRACT Dojran Lake located in south-eastern part of the Balkan is shared by Macedonia and Greece. This valuable water body and its ecosystem are vulnerable both to climate and anthropogenic impacts. Within the period 1988-20002, the Dojran Lake water level decreased seriously (6 m) and the littoral zone of the lake became dry. This water level decline together with the simultaneous water quality deterioration resulted in a biodiversity diminish and plankton reduction. the attack on the ecosystem had a harmful impact on the economy in the region. In the last decade, the water increasing trend of the lake water level has been observed. How much the lake is impacted by natural climatic causes, and how much by human activities in the watershed, is a question that can not be answered easily. The main obstacle for Dojran Lake sustainable water resources management is the fact that there is no exchange of data and information between Greece and Macedonia. Hydrological analysis is obtained using data measured for the period 1951-2010 at the meteorological and hydrological Nov Dojran gauging station located on the Macedonian side. The aim of the paper is stimulation of a close international interdisciplinary monitoring and cooperation. Of crucial importance is to facilitate the free and unrestricted exchange of data and information, products and services in real and non-real time on matters relating to the safety and security of society, economic welfare and the protection of Dojran Lake environment.

International Journal of Environmental Sciences & Natural Resources

Abstract: Modern hydraulic engineering has been and remains to a large extent based on experiment... more Abstract: Modern hydraulic engineering has been and remains to a large extent based on experimental investigations. Mathematical modeling techniques have progressed rapidly due to the advent of high-speed digital computers, enabling the equations of motion coupled with semi-empirical relationships to be solved for complex flow such as pipe network analysis, pressure transients in pipelines, unsteady flow in rivers, etc. There are many cases, particularly where localized flow patterns cannot be mathematically solved, when physical models are steel needed. The hydraulic model investigation of the evacuation structures of dam “St. PETKA ” on Treska River has been performed in Hydraulic laboratory at the Faculty of Civil Engineering in Skopje. The model was designed and constructed in scale 1:40. The evacuation structures that have been investigated are: diverse tunnel with intake structure, shaft spillway with spillway tunnel and output portal and bottom outlet with intake structure. T...

Dojran Lake with its hydrological basin is a closed hydrological system with natural inflow of wa... more Dojran Lake with its hydrological basin is a closed hydrological system with natural inflow of water to the lake, but no natural outflow. Recharge of the lake is from direct surface and underground inflow. Within the period 1950-1960 the lake faced with extremely high water level that was not favorable for the development of fishing. It was built an artificial channel to regulate the water level in the lake and control the water use at Greek side of the lake. In the period 1988-2000, the water level in the lake continuously was declining. Water level declination caused ecological catastrophe for the flora and fauna in the lake and lake's basin that was inconvenience for the basic economy in the region, tourism and fishing. The reasons for declining the water level in the lake are not clearly identified, and they are located in unfavorable hydrological conditions expressed through longer dried period or uncontrolled usage the water from the lake. In 2002, the Republic of Macedoni...

Presented in this paper are the results of the hydrological analysis of the Kalimanci dam basin c... more Presented in this paper are the results of the hydrological analysis of the Kalimanci dam basin carried out for the purpose of redefining flood waters. The analyses of the physicalgeometrical characteristics of the drainage area carried out by use of DTM (Digital Terrain Model) and application of SWAT (Soil & Water Assessment Tool), a hydrological analysis module from the Geographic Information Software (GIS), are presented further in the text. Flood waters with different return periods will be redefined by use of statistic methods based on data from measurements of Bregalnica river flow (1961-2005) and Kamenichka Reka river flow (1986-2005). Shown further in the paper will be the results of the calculation of the maximum flood waters (MPFMaximum Probable Flood waters) in the basin. MPF will be calculated by taking into account a series of data on maximum annual daily rainfall, measured at the dam itself, in the period 2005 to 2017. The results of these analyses will be presente...

ABSTACT In the Republic of Macedonia there are three natural lakes: Ohrid, Prespa and Dojran. Of ... more ABSTACT In the Republic of Macedonia there are three natural lakes: Ohrid, Prespa and Dojran. Of these the Dojran Lake is the smallest, but not less significant as a water resource and as a scenic beauty. In the course of the last 15 years this site of natural heritage is threatened because the lake’s water level decreased seriously. The watershed area of the lake and the lake itself are shared by Macedonia and Greece. Recharge of the lake comes from direct runoff, small tributaries and groundwater. Since 1988 the lake surface area decreased from 42 km 2 to 31 km 2 , and more significantly, and the water volume dropped from 262 million m 3 to only 80 million m 3 in The decline of water quantity together with the simultaneous deterioration of water quality resulted in serious ecological impacts. Biodiversity diminished and the reduction of plankton led to a reduction of fish portion. The number of birds also decreased dramatically. The attack on the ecosystem had a harmful impact on ...

International Journal of Environmental Sciences & Natural Resources, Aug 5, 2019

In circumstances where urbanization of areas is done without parallel increase of the capacity of... more In circumstances where urbanization of areas is done without parallel increase of the capacity of water infrastructure facilities (river regulation, water supply system and sewerage systems, drainage and irrigation systems), urban areas face frequent river floods. These problems combined with the global climate change

ABSTRACT Basic hydrological concepts are presented within 11 chapters: Introduction, Hydrological... more ABSTRACT Basic hydrological concepts are presented within 11 chapters: Introduction, Hydrological Cycle, Mathematical methods in hydrology, Discharge curves, Meteorological characteristics, Hydrometry, Hydrography, Surface runoff, Floods, Low waters, Reservoirs.Glossary is also included as well as list of recommended software in hydrological modelling.

Modern hydraulic engineering has been and remains to a large extent based on experimental investi... more Modern hydraulic engineering has been and remains to a large extent based on experimental investigations. Mathematical modeling techniques have progressed rapidly due to the advent of high-speed digital computers, enabling the equations of motion coupled with semi-empirical relationships to be solved for complex flow such as pipe network analysis, pressure transients in pipelines, unsteady flow in rivers, etc. There are many cases, particularly where localized flow patterns cannot be mathematically solved, when physical models are steel needed. The hydraulic model investigation of the evacuation structures of dam "St. PETKA" on Treska River has been performed in Hydraulic laboratory at the Faculty of Civil Engineering in Skopje. The model was designed and constructed in scale 1:40. The evacuation structures that have been investigated are: diverse tunnel with intake structure, shaft spillway with spillway tunnel and output portal and bottom outlet with intake structure. The main objectives of the study are: to confirm the disposition and dimensions of the associate structures, to define their capacities, to define the flow patterns, to define the pressure distribution along the tunnels, to define the backwater influence of the downstream reservoir and to investigate the erosion processes in the river bed downstream. The investigations were performed on two stages: fixed-bed model and movable-bed model. On the fixed-bed model were investigated the capacities, pressure distribution and flow patterns in the structures. On the movable bed-model were investigated the erosion processes in the river bed downstream of the output structure. In this paper will be discussed the summary results that have been obtained within the study on physical model and the focus will be on the results on the shaft spillway.

ABSTRACT Lake Dojran is a transboundary lake in the south-eastern part of the Balkan Peninsula an... more ABSTRACT Lake Dojran is a transboundary lake in the south-eastern part of the Balkan Peninsula and is shared by Macedonia and Greece. The lake is small and shallow but very significant as a water resource and natural wealth. This paper deals with some answers related to the clarification of natural causes. Very often on scientific and institutional level may be heard that the present state of the lake is basically due to decreased precipitation and increased air temperature, or due to climate change effects. The analysis of the basic hydro meteorological parameters, such as precipitation and air temperature, is presented and their correlation with observed lake water level is established. Data that have been used are for the period 1951-2010 from the hydro meteorological station at Nov Dojran on Macedonian Lake side.

Internationally shared water bodies and their ecosystems are vulnerable both to climate and anthr... more Internationally shared water bodies and their ecosystems are vulnerable both to climate and anthropogenic impacts. The case study of this paper is Dojran Lake situated in the southeastern part of the Balkans that is shared by Macedonia and Greece. Within the period 1988-2002, the water level of the Lake decreased seriously and the littoral zone became dry. This water decline together with the simultaneous water quality deterioration resulted in a biodiversity diminish and plankton reduction. The attack on the ecosystem had a harmful impact on the economy in the region. In the last decade, the water increasing trend of the Lake water level has been observed. How much the Lake is impacted by natural causes, hydrology and climate, and how much by human activities in the watershed, is a question that cannot be answered easily. The main aim of the conducted analyses is to simulate undisturbed and disturbed water levels in the Lake. Hydrological analysis and water balance modeling is obta...

Lake Dojran is a transboundary lake in the south-eastern part of the Balkan Peninsula and is shar... more Lake Dojran is a transboundary lake in the south-eastern part of the Balkan Peninsula and is shared by Macedonia and Greece. The lake is small and shallow but very significant as a water resource and natural wealth. This paper deals with some answers related to the clarification of natural causes. Very often on scientific and institutional level may be heard that the present state of the lake is basically due to decreased precipitation and increased air temperature, or due to climate change effects. The analysis of the basic hydro meteorological parameters, such as precipitation and air temperature, is presented and their correlation with observed lake water level is established. Data that have been used are for the period 1951-2010 from the hydro meteorological station at Nov Dojran on Macedonian Lake side.

ABSTACT In the Republic of Macedonia there are three natural lakes: Ohrid, Prespa and Dojran. Of ... more ABSTACT In the Republic of Macedonia there are three natural lakes: Ohrid, Prespa and Dojran. Of these the Dojran Lake is the smallest, but not less significant as a water resource and as a scenic beauty. In the course of the last 15 years this site of natural heritage is threatened because the lake's water level decreased seriously. The watershed area of the lake and the lake itself are shared by Macedonia and Greece. Recharge of the lake comes from direct runoff, small tributaries and groundwater. Since 1988 the lake surface area decreased from 42 km 2 to 31 km 2 , and more significantly, and the water volume dropped from 262 million m 3 to only 80 million m 3 in 2000. The decline of water quantity together with the simultaneous deterioration of water quality resulted in serious ecological impacts. Biodiversity diminished and the reduction of plankton led to a reduction of fish portion. The number of birds also decreased dramatically. The attack on the ecosystem had a harmful ...

Basic hydrological concepts are presented within 11 chapters: Introduction, Hydrological Cycle, M... more Basic hydrological concepts are presented within 11 chapters: Introduction, Hydrological Cycle, Mathematical methods in hydrology, Discharge curves, Meteorological characteristics, Hydrometry, Hydrography, Surface runoff, Floods, Low waters, Reservoirs.Glossary is also included as well as list of recommended software in hydrological modelling.

Scientific Journal of Civil Engineering

Environmental Earth Sciences, 2014

International Journal of Environmental Sciences & Natural Resources

International Journal of Environmental Sciences & Natural Resources, Aug 5, 2019

ABSTACT In the Republic of Macedonia there are three natural lakes: Ohrid, Prespa and Dojran. Of ... more ABSTACT In the Republic of Macedonia there are three natural lakes: Ohrid, Prespa and Dojran. Of these the Dojran Lake is the smallest, but not less significant as a water resource and as a scenic beauty. In the course of the last 15 years this site of natural heritage is threatened because the lake's water level decreased seriously. The watershed area of the lake and the lake itself are shared by Macedonia and Greece. Recharge of the lake comes from direct runoff, small tributaries and groundwater. Since 1988 the lake surface area decreased from 42 km 2 to 31 km 2 , and more significantly, and the water volume dropped from 262 million m 3 to only 80 million m 3 in 2000. The decline of water quantity together with the simultaneous deterioration of water quality resulted in serious ecological impacts. Biodiversity diminished and the reduction of plankton led to a reduction of fish portion. The number of birds also decreased dramatically. The attack on the ecosystem had a harmful ...