Soil Erosion Reduction by Implementing a Carbon Sequestration Project in East of Iran

In this research, the impact of a carbon sequestration project, in the Hossein Abad Plain in Southern Khorasan Province of Iran, on the status of water and wind erosion was evaluated. The study area has a harsh climatic condition with low annual precipitation and is prone to well-known 120-day winds in summer. Since 2005, various soil conservation treatments (plantations, over-sowing, plantation aided by semi-circular rainwater harvesting structures) have been implemented in the area. The importance of this research is that so far there was no comprehensive assessment to indicate the impact of soil conversation measures on soil erosion. Therefore, current research aims to evaluate the effect of the carbon sequestration project on soil erosion during 2004 - 2016. Therefore, water and wind erosion was assessed by the Universal Soil Erosion (USLE) model and Iranian Research Institute of Forest and Rangelands Ekhtessasi – Ahmadi (IRIFR-E.A.) model, respectively. The general trend of water erosion using the USLE model indicates a reduction in soil erosion by greater than 19.9 t. ha-1. yr-1 over the whole study area which is larger than 2300 km2. Accordingly, all treatments had a significant impact on erosion in the study area whereby the greatest reduction in annual rate of erosion occurred in over-sown areas (by 5.92 t. ha-1. yr-1). The lowest erosion rate in 2016 was observed in the afforested areas (3.0 t. ha-1. yr-1). Wind erosion during 2004-2016 was improved from moderate and high erosion intensity classes to the low class in treated areas. According to the results of the USLE and IRIFR-E.A. models, the implemented carbon sequestration project has effectively reduced soil erosion in the study area. Therefore, the continuation of these treatments as well as extension programs to empower local communities is highly recommended.