Reclamation of a Sandy Desert Through Floodwater Spreading: L Sediment-Induced Changes in Selected Soil Chemical and Physical Properties

Floodwater spreading (FWS) for the artificial recharge of groundwater (ARG), is an easy and economical method of desertification control. An integrated approach to desertification control based on FWS for the ARG was adopted in the Gareh Bygone Plain in southern Iran. Deposition of the suspended load (SL), carried by floodwater into the sedimentation hasins and infiltration ponds, stabilizes the drifting sand and reclaims the eroded rangeland on which the ARG projects are executed. Results of some of the physical and chemical analyses performed on the one to four-year-old sediment samples obtained from the first three sedimentation basins at the Gareh Bygone Plain ARG scheme show that of the 19 factors analyzed, only two changed significantly due to the settlement of the SL in the basins: sand content decreased by 7.9 and 3.8% at the 0-10 and 0-30 cm depth respectively; and the ESP increased by 17.2% at the 0-30 cm depth. Regression equations were developed correlating soil content of organic matter,total N,P, saturation percentage and CEC with silt + clay content. These relationships indicate the geological origin of N and perhaps P and the importance of SL in the fertility status of the drifting sand