Effects of wind erosion on soil organic carbon dynamics and other soil properties: Dejgah catchment, Farashband County, Shiraz Province, Iran

Wind erosion effecting on soil carbon losses, should be considered from the standpoints of sustaining farmland productivity and producing accurate national carbon accounts.The worldwide spread of arid and semiarid areas with extensive damage to these areas gives them potential for carbon sequestration. Considering that a large portion of soil carbon is concentrated in 0 to 20 cm soil depth, carbon sequestration increases soil fertility, prevents erosion and improves the hydrological system. This paper introduces a case study in Dejgah catchment, Farashband County, Shiraz Province, Iran, which used to be a typical area with wind erosion and desertification in south western Iran. A field experiment was conducted in this region to investigate changes in soil carbon in relation to wind erosion. Samples were taken randomly from areas of up to 0.25 ha from each of the different wind erosion categories in June 2011. In each site 20 samples from surface layer (0 to 10 cm) and 20 samples from subsurface layer (10 to 20 cm) were collected, then samples from each layer were combined. Finally, two composite sample from each site and 24 composite soil samples were collected from surface layer (0 to 10 cm) and subsurface layer (10 to 20 cm) in 4 different wind erosion categories (light, moderate, high and severe). In the laboratory, each soil sample was thoroughly sieved to 2 mm to remove roots and incorporated litter and air-dried to determine soil physicochemical properties including pH, electrical conductivity, soil texture, bulk density, total nitrogen, and organic carbon content. Analysis results showed some soil properties largely influenced by the severity of wind erosion. In addition the results showed the impact of wind erosion on loss of carbon and nitrogen so that the organic C and N contents decreased significantly with wind erosion development. In addition changes in organic C content had a significant positive correlation with the soil fine particle content (clay) (Pb 0.01) and a significant negative correlation with sand content (Pb 0.01).