Assessment of the effects of floodwater spreading on soil fertility (Case study: Gachsaran floodwater spreading station)

Floodwater spreading is a simple method for extracting floods which in most parts of the country are usually lost. However, floods are usually rich in nutrient and can fertilize coarse-grained alluvial fan and floodplain sediments. Therefore, the aim of this research was the investigation of the effect of floodwater spreading on soil fertility in Gachsaran floodwater spreading station. For this purpose, for measuring N, K, P, EC, pH, organic carbon and soil texture, the soil and sediments were sampled in two depths of 0-15 and 15-30 centimeters from first and second strips of floodwater spreading and also from the representative area (area where floodwater spreading is not performed), and the samples were analyzed in the laboratory. According to the results, the amount of P, K, N, C and EC in two areas did not show meaningful difference but pH, percentage of clay and silt, decreased and increased, respectively in floodwater spreading and representative area and showed meaningful difference. It is concluded that there was no change in soil fertility due to floodwater spreading.