Analyzing Variation of Sediment Yields in Wet and Drought Years

This study presents meteorological and hydrologic drought effects on sediment yield in a small rural basin, Uğrak Watershed in Tokat Region of North Central Anatolia, Turkey. Sediment yield was estimated by using Modified Universal Soil Loss Equation (MUSLE) model for 25 years period. The maximum and minimum sediment yields were estimated in 1980 and 1997 respectively. Historical precipitation and flow data were analyzed to determine meteorological and hydrological drought by Standardized Precipitation Index (SPI) method. Results showed that there was 10-year drought vs. 15-year wet for meteorological and 14-year drought vs. 11-year wet for hydrological conditions. In the meteorologically drought and wet years, the sediment yields were estimated as 6920.7 tons and 18068.2 tons, respectively. In the hydrological dry and wet years, the sediment yields were estimated as 7417.8 tons and 21489.2 tons, respectively. Sediment yields were found similar in meteorological and hydrological wet and also similar in meteorological and hydrological dry conditions. Drought reduced the sediment yield in the study area.