Evaluating the impact of land use uncertainty on the simulated streamfow and sediment yield of the Seyhan River basin using the SWAT model

Abstract

As a result of the increased availability of spatial information in watershed modeling, several easy to use and widely accessiblespatial datasets have been developed. Yet, it is not easy to decide which source of data is better and how data from diferent sourcesafect model outcomes. In this study, the results of simulating the stream fow and sediment yield from the Seyhan River basin inTurkey using 3 diferent types of land cover datasets through the soil and water assessment tool (SWAT) model are discussed andcompared to the observed data. Te 3 land cover datasets used include the coordination of information on the environment dataset(CORINE; CLC2006), the global land cover characterization (GLCC) dataset, and the GlobCover dataset. Streamfow and sedimentcalibration was done at monthly intervals for the period of 2001 2007 at gauge number 1818 (30 km upstream of the Çatalan dam). Temodel simulation of monthly streamfow resulted in good Nash Sutclife efciency (NSE) values of 0.73, 0.71, and 0.68 for the GLCC,GlobCover, and CORINE datasets, respectively, for the calibration period. Furthermore, the model simulated the monthly sedimentyield with satisfactory NSE values of 0.48, 0.51, and 0.46 for the GLCC, GlobCover, and CORINE land cover datasets, respectively. Teresults suggest that the sensitivity of the SWAT model to the land cover datasets with diferent spatial resolutions and from diferent timeperiods was very low in the monthly streamfow and sediment simulations from the Seyhan River basin. Te study concluded that thesedatasets can be used successfully in the prediction of streamfow and sediment yield.