This study investigates the feasibility of using recycled concrete aggregate (RCA) as a partial substitution of natural aggregate in pavement engineering. Despite RCA’s good properties, such as polishing value and freeze-thaw resistance, its use is limited by low resistance to fragmentation and high-water absorption. This paper parent the experimental results of mineralogical-petrographic and physical-mechanical properties of RCA, natural stone (dolerite) and their combination (RCA content—15%, 30%, 45%, and 60%). The tested granular mixtures showed good resistance to fragmentation and wear (LA 22–27%, M_DE 14–15%), as well as satisfactory Polished Stone Value of 55–57, which means they can be used in different layers of pavement structures. According to the obtained testing results, the application of RCA is possible in different flexible and rigid pavement layers and for various traffic loads.

Tailing dump of the mine Grot mine with more than 5.5 million tons of floated material is the highest altitude dump in Serbia. Vegetation is not developed on it at all. The behavior of heavy metals in the flotation tailing dump has recently been analyzed in the literature. Mineralized dust is observed on the surrounding soil demonstrating its recent pollution. This land is tilled in a primitive way. The analysis of soil shows the presence of heavy metals of anthropogenic origin. The concentrations of these materials vary with the configuration of terrain and weather conditions. Lead is the most toxic of found heavy metals in soil.

The research was conducted to determine the soil organic carbon (SOC) stocks in relation to the altitude in Serbia. The database included a total of 1,140 soil profiles. SOC were investigated at different the altitudes (0-200 m, 200-500 m, 500-1,000 m, 1,000 - 2.000 m) and at two soil depths (0-30 cm and 0-100 cm). Statistical correlation was done for five regions where locations were grouped according to the spatial distribution. The results showed that the highest mean values of SOC were measured on the terrain that includes mountains with the altitudes of 1,000-2,000 m and covers an area of 11.5% of the territory of Serbia. The lowest obtained result is related to the lowland areas with the largest number of locations. Greater variability in the results of SOC stocks were found at the higher altitudes and the greatest on the low mountains of 500-1,000 m altitude. There is a medium to strong statistical dependence of the altitude with the SOC stocks at two soil depths (0-30 cm and 0-100 cm). The result indicate that the relationship between SOC stocks and altitude varies between the regions. This study shows that altitude is an important factor affecting SOC stocks.

The Ibar River is an international river whose watercourse passes next to numerous technogenic landfills and chemical-industrial complexes. They can affect the quality of water in the river, as well as the quality of overbank sediments. The river flows into the West Morava River near Kraljevo and it represents its largest tributary. The analysis of the overbank sediments of Ibar tributaries showed high concentration of heavy metals at some points. The statistical analysis of the content determined the existence of two synthetic factors around which heavy metals were concentrated. The comparison of the chemical composition of overbank sediment with the composition of geological and pedological substratum on which they were developed showed that the increased concentrations of heavy metals were mostly a product of geological and pedological composition of the river’s substratum and basin, and had no connection with (possible) anthropogenic factors. However, due to the sensitivity and proximity of potential pollutants, the necessity to constantly monitor chemical composition of overbank sediments in the river basin was determined.