Yarı-kurak bölgelerde rüzgâr erozyonu tehlikesinin değerlendirilmesi: Bölgesel ölçekte model geçerlilik çalışmaları
Özet
Wind erosion is a critical environmental problem that threatens mainly the arid and semi-arid regions. Usually this problem is associated with desertification, poverty and other environmental and socioeconomic problems. As vegetation is one of the vital factors for the protection of the soil surface against erosive winds, this thesis aims to improve the knowledge on the effects of vegetation cover and land use on regional scale wind erosion by improving of measurement equipment and methods and by the help of wind erosion models. Thus, a new method of portable plot for measuring the wind erosion at the regional scale was developed. Furthermore, the effects of vegetation pattern and the transitions on wind-blown sediment transport were investigated by the downscaling of regional scale conditions in wind-tunnel experiments. In the modeling part of this thesis, the field scale wind erosion model of RWEQ (Revised Wind Erosion Equation) was adjusted, calibrated and validated against ground data collected from different land uses in the Khanasser valley region, Syria. Moreover, a new process-based regional scale model of RS-WEQ (Regional Scale Wind Erosion Equation) was developed. The results of this thesis showed that (1) the adjusted, calibrated and validated RWEQ model is applicable for different land uses in semi-arid regions. (2) the portable plot strategy is a promising method for observing the wind erosion at the regional scale. (3) the vegetation pattern and the border between different land uses have significant effect on the quantity and intensity of wind-blown sediment transport. (4) the developed RS-WEQ regional scale model predicts mass flux, soil loss and deposition for all land covers in a region, including the spatial pattern of these variables within arable fields and thus this model is applicable to assess the wind erosion problem in the vulnerable regions.