Anthropogenic influence on erosion intensity changes in the Rasina river watershed - central Serbia

Abstract

The amount of eroded material in the Republic of Serbia has decreased in the last few decades. The aim of this research is to analyse changes in soil erosion intensity in the Rasina watershed from 1971-2011, caused by factors including changes in land-use, the population and number of households, migrations, and erosion control works. Due to changes in the intensity of erosion processes, the annual gross erosion rate in the study area decreased by 116,140.2 m(3) year(-1), while the sediment yield decreased by 52,727.2 m(3) year(-1). The value of the erosion coefficient was reduced from Z = 0.39 in 1971 to Z = 0.30 in 2011. In this 40-year period, there were no significant changes in natural conditions, and the anthropogenic influences were responsible for the reduced erosion intensity. In the Rasina watershed, almost 8,500 ha upstream from "Celije" dam were treated by bioengineering works. Since 1961, a decrease in the population was typical for all of the valley and mountain settlements in the Rasina watershed. The percentage of the population engaged in agriculture also decreased during this period, as did the general activity of the population. The analysis shows that the most significant reduction in livestock occurred in the mountain region, which has the best conditions for animal husbandry, followed by the hill region, and finally, the valley region. These results are the basis for water management projects, soil and environmental protection, spatial planning, agriculture, and other human activities.