“…Assessment of the sediment flux of a river system is predominantly dependent upon the number and locations of measuring stations, the amount of available data, reliability, accuracy, the temporal resolution of the data, and finally, the length of the records (Walling, ). A number of key SWAT parameters (for example, SPCON, SPEXP, and PRF) can only have single values across the whole watershed; however, in a large watershed, these parameters may vary considerably and this restriction could affect modeling performance (Gong, Shen, Liu, Hong, & Wu, ). The PBIAS for flow tends to be higher in the validation period as compared to the calibration period, which might be due to over fitting of volume‐sensitive parameters (Bennett, Werner, & Schnorbus, ), assumptions that the calibrated parameters are stationary (and valid for both calibration and validation periods), or not incorporating dynamic land cover.…”