Comparison of Wind Erosion on Various Agricultural Lands

Abstract

This investigation was conducted to compare wind erosion on three different agricultural lands (dryland, wastewater-irrigated land, and freshwater-irrigated land) in southeastern Iran. This region consists of 11500 km 2 of arid to semi-arid lands and is one of the driest regions of the country with high population density. Average annual rainfall of the region ranges between 50 and 60 mm. The temperature data indicate that July is the warmest month, when the temperature rises to more than 50 • C, and January is the coldest month of the year, with a minimum temperature of −12 • C. The warm winds blow over the region of Sistan for about 120 days from June to September. The dominant wind directions are north and northwest. Twenty plots were designed randomly (in a completely randomized design) in this study to compare two irrigated areas, freshwater-irrigated land and wastewater-irrigated land, to dryland (control fields). The treatments were repeated three times. Ten data sets were taken during the experimental period, and the means were calculated and reported. The data indicated that wastewater-irrigated land benefitted from reduced soil erosion, increased soil fertility status (i.e., soil organic matter and nutrient contents), and increased soil moisture content. Soil losses by wind erosion in the wastewater-irrigated land, freshwater-irrigated area, and dryland in the study area were 185.2, 339.8, and 554.4 tons ha −1 , respectively. In addition, the study sites lost 1.3, 2.4, and 4.6 cm of soil by wind erosion, respectively.