Application of geographic information systems in evaluating the development of gully erosion in the steppe zone of Ukraine

On the territory of the steppe zone of Ukraine using GPS and leveling set the coordinates of the vertices, the configuration of borders, height, length, width 400 of cutbanks, gullies and ravines are established. Content of iron in the layer of 0–50 cm is determined. Obtained data is imported into QuantumGis and plotted on the map of the tilled soil of Ukraine. The centers of the clusters of studied objects are detected in the Central and Eastern parts of the steppe. Analysis of the causes revealed a complex of factors. For the year of observations it was revealed that the area of each ravine grew on average by5 m², height by8 cm, length by24 cm, width by21 cm, and concentration of Fe decreased by 20 mg/kg. The main reasons are significant precipitation and sustainable grass cover. Size of the gullies increased by1 m², height – by4 cm, length by14 cm, width by9 cm, concentration of Fe remained unchanged. Due to the fact that woody plants hinder the development of erosion and enrich the soil minerals, ravines feature the decrease in height by1 cmand the concentration of Fe increase at 24 mg/kg, with the values of other indicators unchanged. In the environment of QuantumGis the maps of electronic density and the prevalence of cutbanks, gullies and ravines in the steppe zone of Ukraine were developed. With their help, we determined the dependence between the processes and natural conditions under study, the limiting angles of rotation, the area of gully erosion. Database of the project has been created with regard to the content of trace elements and features of their migration across the ravine profile for the purpose of conducting research and further use in the process of developing appropriate measures to combat erosion.