RAVINE AND GULLY EROSION IN THE HILLY HEADWATER AREAS OF HUNGARY

摘要

Ravine and gully development in the loess mantled hills of Hungary are caused by a combination of natural and anthropogenic processes, mainly trafficking and cultivation. In the non-loessial Cserhat Hills, gully erosion was linked to areas with less than 30% forest and where cultivation had extended to slopes greater than 17%. Human action is the main cause of gully formation. Quantitative studies of rill and gully length were carried out for a range of slope conditions and vegetation types. Loess gullies are incised by rainstorms < 20 mm. Historical documents and maps reveal that on slopes > 5%, gully systems may develop in 100 years and on slopes above 12%, gully systems may develop in 50-60 years. Changes in gully length were estimated by comparing topographic maps dated 1784, 1910 and 1974.