بررسي توزيع افقي ذرات بادرفت و حداكثر ظرفيت انتقال رخدادهاي فرسايش بادي (مطالعه موردي اراضي آيش دشت يزد - اردكان)

Aeolian horizontal distribution and maximum transport capacity of wind erosion events (Case study; Fallow lands of Yazd-Ardakan)

Reducing the length of field along the wind path can be a major factor in providing protection against wind erosion. Therefore, the study of sediment transported by wind versus the field length and maximum transport capacity is necessary. As the wind passes over eroding soil surfaee, the quantity of sediment transported by wind increases until the wind stream becomes saturated. In the other word the mass transported is limited by the emission rate of materials from the soil surface to the air flow, known as transport limiting. The field length required for the wind to reach its maximum capacity depends on the wind velocity and the eomponents of the soil surface. The field data were collected from 1.9ha fallow lands of Yazd-Ardakan plain. Big Spring No Eight (BSNE) samplers were set up to collect samples of horizontal sediment discharge passing through a point. Twelve events data were collected and analyzed started from May 2006 to may 2007. Two methods were adopted to determine the maximum transport capacity; J) Fitting the mathematic equation of Ix = Im~(I-e[-x/hJ)and 2) Direct measurement of transport capacity. Variance analysis and t-test paired data results showd that, there was no significant difference between the results of these two methods.