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Intenzitet erozije zemljišta rezultat je kombinovanog delovanja različitih prirodnih i antropogenih faktora. Ovaj rad ima za cilj da utvrdi agrarne indikatore kao determinante promene intenziteta erozije zemljišta u slivovima Crnice i Rasničke reke. Model potencijala erozije primenjen je za procenu stanja erozije zemljišta za dva perioda 1971. godine i 2010. godine. Koeficijent erozije u slivu Crnice iznosio je Z1=0,390 i Z2=0,360, a specifična produkcija nanosa Ws1=529 m3/km2/god i Ws2=463 m3/km2/god. Koeficijent erozije u slivu Rasničke reke iznosio je Z1=0,437 i Z2=0,374, a specifična produkcija nanosa Ws1=861 m3/km2/god i Ws2=622 m3/km2/god. Ekstremno smanjenje agrarnog pritiska na zemljište, veliki udeo naselja regresivnog tipa od 80 %, kao i intenzivan proces depopulacije rezultiralo je većoj redukciji erozije zemljišta u slivu Rasničke reke. Rezulati ove studije mogu omogućiti donosiocima odluka nove pristupe za adekvatno upravljanje zemljišnim resursima u ruralnim sredinama.

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.

The intensity of soil erosion is the result of a combined action of natural factors and different human activities. This work aims to determine the factors controlling the change of soil erosion. Eleven watersheds from different parts of Serbia were used as the study area. An Erosion Potential Model was applied to estimate the soil erosion status of the watersheds in two periods, 1971 and 2010. The model indicated that the reduction of soil erosion intensity in the watersheds ranges from 12.4% to 82.7%. The statistical analysis examines quantitative relationships and combined effects between soil erosion and socio-economic and main physical-geographical determinants in watersheds. Watershed characteristics were divided into 5 classes, and within each class 22 variables were calculated: two variables relate to erosion, one to topography, two to land cover, seven to demographic and ten to agrarian variables. Correlation analysis and Principal Component Analysis (PCA) have been applied to understand the main variables that contribute to change soil erosion intensity. The PCA identified four components that can explain at least up to 79.06% of the variation of all variables. This study explores new indicators for correlations with changing soil erosion and provides decision makers with access to quantification for environmental impact assessment and decision-making for adequate soil conservation and management programs.

The erosion potential model was applied to estimate the soil erosion status of rural settlements during the years 1971 and 2011. We used univariate and bivariate local Moran’s I indices to detect and visualize the spatial clustering of settlements with respect to changes in erosion intensity and agricultural land use, as well as their mutual spatial correlation. The study area was differentiated into four statistically significant clusters using the calculated bivariate local Moran’s I indices. The statistical analysis examined the two largest clusters, i.e., the high–high and low–low clusters, and the results of the research indicate that the first four principal components explained 70.50% and 73.47% of the total variance, respectively. In the high–high cluster, the low rates of erosion reduction (average Index Z = 98) in the most significant types of rural settlements were determined according to demographic indicators (i.e., the higher population vitality and population density, the smaller share of the old population and the lower average age of the population) and the large proportion of arable land and Neogene sediments. In the low–low cluster, high erosion reduction rates were detected (average index Z = 64). In this cluster, the more statistically significant influence of natural conditions in combination with demographic–agrarian processes (i.e., the larger share of the old population, the higher average age of the population, the lower vitality index and deagrarization) were decisive factors in changing erosion intensity

The key problem of rural settlements in the South Banat district lasted into the 21st century through the spread of depopulated areas. Considering that settlements give a cultural landscape its basic features, that they are the main bearers of functional organization, and the hotspots of geo-spatial transformation, based on quantitative-qualitative indicators this paper analyzes the spatial-demographic determinants of the development of 94 settlements, and the impact of depopulation on the changes in the surrounding forest cover. The time span included in the analytical-statistical research of the demographic components and forest dislocation lasted from 1990 to 2018. Geo-spatial data for forest areas were taken from the Corine Land Cover database. The data obtained were then turned into visual representations, or maps, using the GIS ArcMap 10.8. software. The results indicated that total depopulation has been an ongoing, 30-years process in this area on the one hand, while the forest cover in the depopulated settlements located on the outskirts of the Deliblato sands (a special nature reserve) has decreased, and the forest cover in the depopulated settlements in the zone of the Vršac mountains has increased, on the other. These analyses are useful for obtaining more detailed insight into the state of forested areas in this part of Serbia, which is the least afforested one.