Ali Haghizadeh; Lila Ghasemi
Abstract
In recent years, the flood situation of headwaters of the Dez River in Lorestan Province has increased. This is due to various factors such as climate change, reduction of vegetation cover, and increase in construction in the riparian zone. In 2022, floods occurred several times in the Dez headwaters ...
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In recent years, the flood situation of headwaters of the Dez River in Lorestan Province has increased. This is due to various factors such as climate change, reduction of vegetation cover, and increase in construction in the riparian zone. In 2022, floods occurred several times in the Dez headwaters in Lorestan province. These floods caused significant damage to life and property. Global conceptual models have been developed for more than two decades and their effectiveness in simulating streamflow has been proven. In this study, simulation of runoff rainfall in Silakhor-Rahimabad watershed was done using three daily (GR4J), monthly (GR2M) and annual (GR1A) models. The Nash-Sutcliffe (Nash), root mean square error (RMSE), and bias criteria were used to evaluate the model performance during the calibration and validation periods. The obtained results were highly significant. The GR1A model has Nash coefficients of 86.1 and 71.7 in both calibration and validation periods, respectively, so this model has a very good performance. For the other two models, the GR2M model and the GR4J model, the Nash coefficients in the two calibration and validation periods are 76.7, 70.2 and 61.4, 86.2, respectively. These coefficients also indicate the good and very good performance of these models in rainfall-runoff simulation. However, considering the satisfactory performance of the two evaluation criteria, RMSE and Bias, in the GR1A model, it can be concluded that the GR1A model had a better performance in simulating rainfall-runoff. Finally, the obtained results indicate that the GR4J, GR2M and GR1A conceptual models are suitable models for simulating the streamflow in the Silakhor-Rahimabad watershed.