Wind erosion measurement on fallow lands of Yazd-Ardakan plain, Iran

Wind erosion is a significant problem on 20 million ha of Iran, especially in central plains and coastal areas. Winderosion samplers, meteorological equipments and measurement procedure have been developed over the last twocenturies to measure the particles moving across the field in modes of creep, saltation and suspension. In recentresearch as the first technical measurement in Iran, wind erosion was measured with these advanced procedures. Fielddata was collected from a small (1.9 ha), square, fallow field with nonerodible boundaries. Wind erosionmeasurement equipment containing 14 clusters with samplers at 0.05, 0.10, 0.25, and 0.50 and 1.0m above the soilsurface and a 4× surface creep sampler (0 to 0.02m height by 0.005m wide) was arranged in a circular pattern. Thesampling cluster consisted of an array of five samplers each attached to a pivoting wind vane and each mounted at adifferent height on a central pole. This permitted field erosion data collection regardless of the wind direction andprovided a range of field lengths with a minimum number of sampler locations. A combination equation of power andexponential functions expressed the variation of transition material to a height of 2m. An exponential modeldescribed the horizontal distribution of transported soil in the field. Twelve single events were recorded and analyzedbetween May 2006 and May 2007. Several inherent soil properties such as soil texture, organic matter and calciumcarbonate content affect the erodibility of soil and change very slowly in research time. Other properties, such assurface roughness and aggregate crust strength are temporal and change rapidly in response to climatic conditions.Total soil mass transported across the fallow field was measured at 220.93 kg/m per year and soil loss at 1.356 kg/m2(13.56 ton/ha) per year.