European Geographical Studies

3-7

Authors: Elizbar Sh. Elizbarashvili, Mariya E. Elizbarashvili, Shalva E. Elizbarashvili

The probabilities of the occurrence of individual hazardous weather phenomena and their complexes in the city of Tbilisi were studied: hot days, strong winds, heavy winds, fog, hail, blizzard. The most common of the phenomena under consideration are hot days. Even in spring and autumn their probability is quite high, and in summer it reaches 0.83. During the cold season, there is a high probability of fog. Strong winds occur at all times of the year. Their probability is not very high, but is characterized by a significant coefficient of aggressiveness. Hail is especially aggressive and occurs in the warm season. The likelihood of a snowstorm developing is negligible. Possible social and economic risks associated with these phenomena have been identified. Both social and economic risks are greatest from fog and strong winds. In winter, the economic risk from fog per incident can be more than 3.6 million US dollars, in the fall - more than 2.3 million US dollars. The social risk from strong winds is greatest in spring, although the risk is also significant in other seasons. The economic risk from strong winds in spring exceeds $2.6 million, and in winter exceeds $2 million. These phenomena occur several times throughout the year, so the economic risk can range from several to tens of millions of US dollars per year.

19-27

Authors: Thi Hoai Thu Trinh, Quang Van Nguyen

This study presents a comprehensive analysis of the tropopause height and temperature over the Vu Gia-Thu Bon river basin using multi GNSS-RO (Global Navigation Satellite System Radio Occultation) data. The findings reveal an average tropopause temperature and height are 195.341K (±0.166K) and 16.467 km (±0.079 km), respectively. Monthly fluctuations in tropopause altitude range from 15.898 km (min) in July 2008 to 17.208 km (max) in February 2010. The highest temperatures and lowest altitudes occur from May to September, while the lowest temperatures and highest altitudes are observed from October to April. Tropopause height varies from 15.848 km to 17.208 km, with deviations from the mean ranging from -0.079 km to 0.232 km. Tropopause temperature ranges from 192.647K to 197.797K, with deviations from the mean ranging from -0.166K to 1.893K. The multi-regression analysis shows a significant upward trend in both tropopause temperature and height from 2002 to 2017. The Tropopause temperature increases approximately by +0.2K with an average yearly increase of 0.013K, while the tropopause height shows an upward trend of about +0.1km with an average yearly increase of 0.008km. The annual and semi-annual periods display sinusoidal variations in both temperature and height, with the annual cycle showing a larger amplitude. These findings highlight the impact of global temperature change on troposphere dynamics, emphasizing the importance of monitoring and understanding these changes for climate forecasting in the Vu Gia-Thu Bon river basin.

3-11

Authors: Thi Nam Phuong Doan, Van Trung Nguyen, Thi Thanh Hoa Pham, Thanh Ha Tran, Thi Thu Ha Le

In recent years, forest fires have occurred frequently in Vietnam due to the influence of climate change and human activities. This paper presents the results of modeling the risk of forest fires in the west of Nghe An province (north-central Vietnam) from remote sensing and GIS data. 09 factors affect the risk of forest fire, including vegetation cover (NDVI index), soil moisture (NMDI index), elevation, slope, aspect, wind speed, land surface temperature, average monthly precipitation and population density are used to build a model for mapping forest fire risk based on Suppor Vector Machine (SVM) algorithm. The past forest fire data is collected from the database of the Forest Protection Department (Vietnam Ministry of Agriculture and Rural Development) to evaluate the accuracy of the model. Different values of cost parameter (C) are tested to select the value with the highest accuracy in predicting forest fire risk. The results obtained in the study can be used effectively for monitoring and early warning of forest fire risk in the localities, helping to reduce damage caused by forest fires.

3-39

Authors: Nikolai A. Bityukov

The article is devoted to the analysis of the formation of the hydrological regime of the mountain rivers of the Sochi Black Sea region. Due to the peculiarities of the geomorphology and relief of the region, as well as climatic conditions, the main zone of river flow formation is the high-mountain and mid-mountain part of the river basins. Thus, the Mzymta river in the winter period of the hydrological year (from November to March) has a minimum flow, and the average increase in flow is 2 times in the warm season (from April to October). The remaining rivers of the region, due to the predominant rain supply, are characterized by increased runoff in the cold season. There are analyzed the features of the flow formation along the length using the example of two main rivers of the region that have flow observations (the Mzymta and Sochi rivers). From the graphs of changes in water flow rates and total runoff layers, it was found that the greatest water content of rivers falls on the average flow of the river. At the same time, a third of the length of the rivers, which fall on the low-mountain and low-hilly zones, significantly loses flow to the formation of intra-pebble runoff. The most significant in this regard are the values of the runoff on the Sochi River, which give a zero increase in water consumption from the 15-km estuary part of the basin (58 km2 is an increase in the catchment area).

55-62

Authors: Lali Shavliashvili, Elina Bakradze, Elizbar Elizbarashvili, Ekaterina Shubladze, Gulchina Kuchava

The expedition works were held in the territory of the Madneuli enterprise of Kvemo Kartli region in 2020, where brown soils are spread. In order to study the migration of heavy metals in the soil, taking into consideration the wind direction, the samples of soil was taken from 0-100 (0-10, 10-20, 20-40, 40-60, 60-80, 80-100) cm depths, in North from the source of pollution direction (Background) – weak winds direction, 500 m from the enterprise and in the direction of a strong wind in the West and 300 m from the enterprise. In the soil samples were determined general forms of heavy metals Cu, Zn, Pb, Mn, Ni, Cd, Co, As, Ag, Cr, Fe by Plasma-emission spectrometer at ICP-OES. The quality of some heavy metal contamination of soil is revealed in connection with Clark; In contaminated areas, the relatively high concentrations of heavy metals are observed in the upper layers, which are due to the prevailing winds. in the samples taken from the north (background-weakest wind direction) heavy metal content were less. Specifically, from the background and contaminated areas the copper content with 0-10 cm layer 63.22 (1.4) and 324.13 (6.9) mg/kg; 80-100 cm depth decreases copper content and is 22.15 and 156.17 (3.3) mg/kg. Similar situation is in case of zinc. Migration of heavy metals is reduced by increasing depth and approximately 1-5 times exceeding the relevant background importance. In the samples taken from the background areas, some metals (cadmium, arsenic and silver) are high content, which is due to their existence in the soils of the region. At the same time, it is noteworthy that their Clark indicator is low and therefore 0.13; 1.7 and 0.07, which leads to increasing the Ratio concentration of these metals in relation to Clark. As it appears from the data, the soil meets in the categories of copper, zinc and arsenic in the category of slightest pollution (<10) category; In cadmium and silver cases – in average pollution (10-30); And the concentrations of lead, manganese, nickel, cobalt and chromium do not exceed Clark. Correlation links are investigated between the concentrations of different metals in the upper layers of the soil. The correlation coefficient is the largest between Cu and Zn concentrations. It is positive and equals 0.77, determination Coefficient (R2) is 0.58 among the Cu-Zn concentrations. Correlation coefficient between Cu and Co concentrations are 0,62, determination coefficient of Cu-Co concentrations is 0.38. In all other cases the correlation coefficient is negligible and can be neglected.

3-7

Authors: Nana Berdzenishvili, Ninaka Berdzenishvili

The impact of climate change on a particular species can ripple through a food web and affect a wide range of other organisms. Climate change and shifts in ecological conditions could support the spread of pathogens, parasites, and diseases, with potentially serious effects on human health, agriculture. Climate change, along with habitat destruction and pollution, is one of the important stressors that can contribute to species extinction. It has been established that the most vulnerable system is the Black Sea coastline, which has a strategic importance for the rehabilitation of the country’s economy and development of foreign trade.

31-36

Authors: Jelisavka Bulatović, Goran Rajović

The Trešnjevik smail river springs at the foot of the Trešnjevik pass (1573 m above sea level), formed by "Water Source" and "Smaller Watercourse". In the upper course, on the left side, it receives small streams from the localities of Garevina and Osoja, while in the middle course, it receives streams Lomovi 1 and Lomovi 2. It flows into Rajova (Rajović) Rijeka near alluvial plains Milićević and alluvial plains Rajović. In the middle course, the Trešnjevička River on the left side formed the alluvial plain of Novović, at the foot of Lomovi a small alluvial plain on the right and left side and the most widespread in the basin of Rajova (Rajovića) River – alluvial plains Milićević. In Trešnjevičkoj smail river their habitat in the river and found the brown trout, which at the present time there are less and less. There are many reasons for the poor state of the brown trout. The two most destructive techniques are dynamite hunting, followed by net hunting. On Trešnjevik environment and you can spend a great time – skiing, walking, doing sports or hunting and fishing, and the environment itself is a great choice for all kinds of recreation in nature, as well as for all lovers and admirers of almost untouched nature.

48-56

Authors: Lali U. Shavliashvili, Marine A. Arabidze, Elina M. Bakradze, Gulchina P. Kuchava, Georgi I. Kordzakhia

In 2019, in Ambrolauri municipality, the level of soil contamination with arsenic as a result of exposure to hazardous industrial waste containing arsenic of the Racha Mining Chemical Plant was studied. In particular, a study was conducted on arsenic contamination of the soils of the villages Uravi, Abari, Utseri, Likheti and Sori Valleys. Revealed that: According to the results of the study, of Uravi soils are the most polluted in arsenic; There is less arsenic pollution in the village of Utsera, Sori Valley and the village of Likheti (average level of pollution); The village of Abara is relatively clean, a small area where arsenic contamination was observed. It should be noted that in all cases the arsenic content is higher in the soil top (0-5 cm depth) than in the lower layer (5-20 cm depth). The health condition of the population of Ambrolauri municipality has been revealed. Based on the 2016 statistical data of the National Center for Disease Control and Public Health, the population of Racha-Lechkhumi and Kvemo Svaneti among the regions of Georgia has the first place in terms of malignant tumours and diabetes.

68-77

Authors: Tsisana Z. Basilashvili

Due to global warming and the Earth’s overpopulation, vital fresh water resources are expected to suffer irreplaceable losses; thus, fresh water shortage is the most acute problem of our time. The paper presents the characteristics of the state and problems of freshwater resources, there is a large disproportion in their distribution. Having studied the long-term dynamics of river water flow, it was found that with increasing intensity of the Caucasus glaciers’ melting, river water flow increases here while in non-glacial zones, it decreases. Numerical values of their annual changes have been established. Particularly acute problems of water scarcity are expected in eastern Georgia, where, due to the dry climate, the shortage of irrigation water will lead to a decrease in yield – the source of livelihood of the local population. Expected droughts will contribute to desertification processes. Therefore, it is necessary to rationally use the available water resources and take measures to replenish them in order to overcome the expected economic and social crisis and ensure environmental safety.

3-9

Authors: Nana M. Berdzenishvili

The wind regime of one of the regions of Georgia-Imereti, located in its central part, on the southern winding slope of the Greater Caucasus, is systematized. The repeatability of the prevailing wind directions is established. According to the monthly average data, the repeatability of the winds of the eastern regions reaches 53 %, and the repeatability of the winds of the western regions is 43 %. At night, the frequency of easterly winds increases to 69−70 %, and the frequency of westerly winds is greatest in the afternoon, amounting to 40−50 %. The highest average annual wind speed is observed in Mta-Sabueti and is 9.2 m/s where the wind speed throughout the year is quite high, amounting to 7.9-10.6 m/s. Increased wind speeds in Kutaisi up to 5 m/s are due to the phenic effect, in other places the average annual wind speed mainly does not exceed 3 m/s. The range of changes in the average annual number of days with strong winds ranges from 12 (Korbouli) to 162 days (Mta-Sabueti). The maximum number of days with a strong wind was recorded in Mta-Sabueti-222, in Kutaisi the maximum number of days with a strong wind is 124, and in other places it ranges from 40−80 days.

21-38

Authors: Sudipa Halder, Malabika Biswas Roy, Pankaj Kumar Roy

Climate change is an important consequence of the land degradation. There is an urgent need to manage the rapidly changing dynamicity of the earth surface in a sustainable way. Garbeta block of West Medinipore has been chosen for the study to identify the sources of landform vulnerability which is severely affected by rill and gully erosion. Land use and land cover analysis of three distinct years has been computed which clearly shows the increase of dry fallow land over the region from 1989 to 2018 making it more assailable to sheet and rill erosion during the monsoonal period and encourage poor ground water recharge. An association map between land use/land cover and elevation has been prepared using GIS software and Statistical Package for the Social Science (SPSS) to find out the dominancy and similarity of a particular physical and human activities over the region according to the relief. The environmental indices like Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) has been prepared to analyse the ecological stability of the region. Therefore land use and land cover analysis is an important tool for the policy makers and stakeholders to implement conservation schemes in the light of sustainability.

50-60

Authors: E.Sh. Elizbarashvili, M.E. Elizbarashvili, Sh.E. Elizbarashvili, M.G.Pipia, N.Z. Chelidze

Based on observations from more than 20 meteorological stations, we investigated the number of days with precipitation of 50 mm and more, the maximum daily and maximum five-day precipitation, periods of precipitation, probability and intensity on the territory of Georgia. A classification of intense precipitation has been carried out and a map of the maximum intensity of precipitation has been developed. The trends of the long-term change in the climatic characteristics of extreme precipitation are estimated, some statistical differences in mean values of characteristics for different averaging periods are revealed. The obtained results expand our understanding of the geography, structure and dynamics of the characteristics of catastrophic precipitation in the territory of Georgia.