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

Document Type: Research Paper

Authors

1 Academic staff member, Natural Resources and Desert Studies faculty & ADRI, Yazd University, Yazd, Iran

2 Assistant professor, Natural Resources and Desert Studies faculty & ADRI, Yazd University, Yazd, Iran

3 Professor, Faculty of Agriculture, University of Tehran, Karaj, Iran

4 Assistant professor, Research Institute of Forests and Rangelands, Desert Division, Academic Staff Member, Tehran, Iran

5 Assistant professor, Faculty of Agriculture, University of Tehran, Karaj, Iran

Abstract

Wind erosion is a significant problem on 20 million ha of Iran, especially in central plains and coastal areas. Wind
erosion samplers, meteorological equipments and measurement procedure have been developed over the last two
centuries to measure the particles moving across the field in modes of creep, saltation and suspension. In recent
research as the first technical measurement in Iran, wind erosion was measured with these advanced procedures. Field
data was collected from a small (1.9 ha), square, fallow field with nonerodible boundaries. Wind erosion
measurement equipment containing 14 clusters with samplers at 0.05, 0.10, 0.25, and 0.50 and 1.0m above the soil
surface and a 4× surface creep sampler (0 to 0.02m height by 0.005m wide) was arranged in a circular pattern. The
sampling cluster consisted of an array of five samplers each attached to a pivoting wind vane and each mounted at a
different height on a central pole. This permitted field erosion data collection regardless of the wind direction and
provided a range of field lengths with a minimum number of sampler locations. A combination equation of power and
exponential functions expressed the variation of transition material to a height of 2m. An exponential model
described the horizontal distribution of transported soil in the field. Twelve single events were recorded and analyzed
between May 2006 and May 2007. Several inherent soil properties such as soil texture, organic matter and calcium
carbonate content affect the erodibility of soil and change very slowly in research time. Other properties, such as
surface 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.

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