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Sediment transport time series have shown a severe change in the suspended sediment load transported by the Velika Morava River (Republic of Serbia) during the last few decades. The research objectives of this study were to determine the suspended sediment trends, and to assess the impact of variations in precipitation and human activities on the suspended sediment load. The causes and timing of this severe decrease were analyzed, and the results show that there has been a signifcant sudden shift downwards for the suspended sediment load (p

Dynamics of totall dissolved solids (TDS) and suspended sediment concentrations (SSC) were monitored on the river Nišava at the hydrological station Dimitrovgrad. Water samples were collected each day in the period from 01.01.2010–31.12.2010. TDS concentration followed a seasonal pattern imposed by the availability of water, with higher concentrations recorded in low-flow periods and lower concentration in the highflow period. SSC was extremely variable and dominate mainly with specific high-flow events. Mean annual discharge (Q=6.68 m3/s, q=13.9 l/s/km2) over the year was 3.3 times higher than the average for the period of 50 years. In the study period, the annual transport dissolved load (Qd) was 36962.8 t (specific load Qds=76.7 t/km2/yr) and suspended sediment load (Qs) was 98861.9 t (specific load Qss=205.1 t/km2/yr). The transport of dissolved load and suspended sediment load shows temporal variations in different seasons. The analysis revealed that the maximum loads was transferred during the winter (Qd=43.3% and Qs=56.8% of the annual transport) and spring season (Qd=37.9% and Qs=38.9% of the annual transport). A comparative analysis of Q, Qd, and Qs show that the suspended sediment shows greater variability and exponential pattern of transport. For instance, 90% of the time was required to export 65% of the total water and transported 77% of the total dissolved load and only 22% total suspended sediment load. The most extreme precipitation episodes and extreme temperatures events was recorded in February 2010. The floods in February contributed by 44.8% of the total Qs transport over the study period. These findings have important implications for water resource management in the context of sediments mobilization, erosion, channel management, water quality and ecological functions.

One of the biggest problems of environmental protection in Serbia is landfills. It is often a case that the economic interests are predominant in the landfill sitting, thus, most landfills are not located according to standards. This study shows that detailed geological data assets combined with geographical modeling represents a reliable way to define and locate the landfill site. Geological evaluation is discussed in detail with regard to bedrock lithology, quaternary geology, geological structure, hydrogeology, surface runoff patterns, and topography. An approach combining geographical modeling and geology is presented for determining the sites suitable for landfill selection with respect to their geologic favorability. As opposed to numerous research papers on this topic, in the methodological procedure, special importance is devoted to the analysis of the geological criteria. In this way, it is significantly easier to determine the landfill area with the best characteristics due to geological structure and lithology which unequivocally and precisely indicates inadequate territories for candidate sites. The multicriteria decision analysis (MCDA) is based on geological criteria upgraded with road (primary, residential, secondary, and tertiary), settlements network, railway, airport, infrastructure, land use, hypsometry aquifer, wetland, and surface water. The score values are divided into four classes, i.e., restricted areas, suitable but avoid, suitable, and most suitable. Combining geographical modeling with geology led to the recognition of two locations to be most favorable for landfill site located in the most suitable area, which represents 25.3% of the study area.

This study expounds the dynamic relationships among agricultural land-use change, rural population migration, and sediment transport. The variability of suspended sediment load was detected by Mann–Kendall and Pettitt tests. From 1961 to 2007, the annual trend in suspended sediment concentration and sediment load demonstrated significant reduction (α = 0.001), with decreasing rates of 0.0144 g/L/y and 84.7 t/y, respectively. An abrupt change-point was detected in 1984 for the sediment load (p = 0.0001). The double-mass curve method and regression analysis of sediment load versus precipitation were used to quantify the effects of climate change and human activities on sediment load variations. The changes in sediment load were predominantly impacted by human activities (89%), while precipitation explained 11% of the reduction in suspended sediment. An important land-use change recorded in the Južna Morava river basin comprised the abandonment of agricultural lands due to depopulation processes, as well as economic and social changes, which was followed by significant impacts on soil erosion and sediment transport. Land abandonment was most pronounced in marginal mountain or semi-mountainous areas, where agriculture was until recent decades traditional or semi-traditional. The results of the correlation matrix were significant at the p &lt, 0.05 level, demonstrating that the decrease of rural population, agricultural land, and arable land were directly related to the decline of suspended sediment. High correlation coefficients were found between anthropogenic indicators and sediment parameters, ranging from 0.94 to 0.97.

In many Eastern European countries, the standard of living increased as a result of the process of industrialization in the second half of the 20th Century. Consequently, the population in rural areas with small-scale farming decreased due to the availability of employment elsewhere. This directly impacted soil erosion (and thereby sustainability of the land), but the degree and direction are not well known. This study investigates two municipalities within Serbia, their change in population and its impact on land use changes and soil erosion. The standard of living increased after the industrialization process in the 1960s within these municipalities. The erosion potential model is used to calculate gross annual erosion. The changes related to population and arable land in rural settlements are analyzed according to proportional spatial changes. The results show an overall decrease of erosion intensity in the study area. In addition, two basic findings are derived: first, the highest level of human impact on soil is in rural settlements at the lowest elevation zones, where erosion intensity shows the least amount of decrease; and, second, the most intensive depopulation process, recorded in higher elevation zones, indicates a rapid decrease of erosion intensity.

Considering recent weather events in Serbia (especially the floods in 2014), a need has arisen for research that would help in identifying extreme weather phenomena. Therefore, the aim of this paper is to determine the thresholds above which intense precipitation can be considered as extreme precipitation events in Serbia. In this study, we determined the frequency of precipitation occurring at an intensity above the threshold of an extreme phenomenon (1961–2015), as well as the frequency of precipitation occurring at or above the absolute daily maximum in the reference period (1961–1990). The study sample included daily rainfall observations from 28 stations from the national meteorological network in Serbia. Applying a decile method, all the stations recording precipitation above the threshold of dangerous phenomena on the same day are classified into the corresponding decile. The threshold value was determined as the average value of the extreme annual precipitation in the analyzed period. The cases that are due to the high prevalence listed in the last decile are considered extreme. The results showed that the critical number of observation points above which an event is considered extreme precipitation event is 6.21, and a warning of the danger could be ensured only in the case of neighboring stations in the network. The threshold of extreme precipitation events for the individual stations ranges up to 130 mm. The obtained results might be used to mitigate the effects of extreme precipitation events in Serbia in the future.

Torrential floods are the most frequent natural hazard events in Bosnia and Herzegovina. The increase of intensive rains in Bosnia and Herzegovina over last years, as a consequence of the climate changes, has triggered many torrential floods, which have generated a lot of damages and losses of human lives. This study was focused on development of torrential susceptibility model using GMM Method and GIS in the Vrbas river basin as an attempt to create a new methodological approach which can be used on other river basins in Bosnia and Herzegovina. First, a total of 174 torrential basins were identified in the Vrbas river basin, as a base for creating an inventory map, which was a base map for the assessment of torrential floods susceptibility. The GIS Matrix Method and six influencing factors were used for generation of Torrential Flood Susceptibility Model. Based on the obtained values of Torrential Flood Susceptibility Model for the Vrbas river basin, 45.52% of the study area is within strong and very strong susceptibility category. The Torrential Flood Susceptibility Model was validated using a "degree of fit" method. Validation indicators of the TFSM show that the 80.04% are in the category of strong and very strong susceptibility, while only 4.37% are in the category of very low and low susceptibility. This fact suggests that used methodology based on GMM method and used influencing factors enable delimitation of the area with high and very high susceptibility to torrential floods into the Vrbas basin. Therefore, used methodological approach represents a good base for future research, and it has potential for the practical use and should be tested in other river basins in Bosnia and Herzegovina.