NATURAL CARBON SEQUESTRATION IN SOILS CLEANED FROM LAND MINES ON THE TURKISH SYRIAN BORDER

Loss of Soil Organic carbon (C) from the agricultural soils is well documented. Conversion of an agricultural soil to natural habitat is expected to help recover the soil carbon lost. Cleaning of mines after 63 years from the formerly nationalized farmland on Turkey's borders with Syria gave an opportunity to determine the average rate of C sequestration in the last 63 years. As the demining is in the process, we opened 8 profiles from the formerly mined area near Nusaybin district of Mardin Province and compared with 8 selected similar cultivated soils nearby. The area is dry with an annual average precipitation of 400 mm and soils have high clay and low organic matter contents and they are typically calcareous. Samples were collected from 10 cm interval up to 100 cm. They were used to determine major characteristics and specifically their organic matter contents. Average total organic matter of 100 cm thick soil of mined area is 8.22 kg C m(-2) or 82.21 tons ha(-1). When two groups of soils are compared it was found that the soils mined had accumulated only about 46.85%. This corresponds about 0.74% C per year, or 0.61 tons ha yr(-1) recovery or annual accumulation rate of organic carbon. This is still a much higher rate value of annual accumulation in soils which is a near steady state pedogenesis after several thousands of years. This suggests that the recovery process is rather slow and use of organic amendments is needed to speed up the process, especially in arid regions.