Parameter evaluation for soil erosion estimation on small watersheds using SWAT model

Abstract

This research was undertaken for the evaluation of soil erosion using the semi-distributed basin scale SWAT model for four subcatchments of the Dhrabi River Catchment (DRC), which is located in the Pothwar Plateau region. Two subcatchments (catchment-25 and -31) are characterized by gullies while the other two (catchment-27 and -32) are managed with terraced landuse system. The performance of the model was satisfactory with coefficient of determination (R 2 ) = 0.67 to 0.91 and Nash-Sutcliffe efficiency (E NS ) = 0.54 to 0.85 for both surface runoff and sediment yield during the calibration (2009)(2010) and validation (2011) periods. The P USLE factor was found to be the most sensitive parameter during model calibration.It was observed that all of the rainfall-runoff events occurred during the monsoon season (June to September). The estimated annual sediment loss ranged from 2.6 t/hm 2 to 31.1 t/hm 2 over the duration of the simulation period for the non-terraced catchments, in response to annual precipitation amounts that were between 194.8 mm to 579.3 mm. In contrast, the predicted annual sediment levels for the terraced catchments ranged from 0.52 t/hm 2 to 10.10 t/hm 2 due to similar precipitation amounts. The terraced catchments resulted in 4 to 5 times lower sediment yield as compared to non-terraced catchments. The results suggest that there is a huge potential for terraces to reduce soil erosion in the DRC specifically and Pothwar area generally, which have proven to be an efficient approach to establishing soil and water conservation structures in this region.

The Impacts of Land-Use Input Conditions on Flow and Sediment Discharge in the Dakbla Watershed, Central Highlands of Vietnam

“…This focused on predicting the impacts of land management practices on water and sediment in large complex watersheds over long periods of time [29]. There are many papers that have used this hydrological model to simulate water discharge and base flow [30][31][32], as well as sediment for specific storm events [33]. This model has also been used to show the relationships between sediment, rainfall, and simulated surface runoff [34,35].…”

Micro-Watershed Management for Erosion Control Using Soil and Water Conservation Structures and SWAT Modeling

“…The weather station location and lookup tables of daily precipitation and temperature (maximum and minimum) data were loaded to link them with the required files. First, the model was simulated for each watershed with validated parameters adopted from Hussain et al [14] without the consideration of the conservation structures, and then interventions of the soil and water conservation structures were made by modifying the parameters for surface runoff and sediment yield. The setup of model for each watershed with and without the consideration of the conservation structures is shown as the right and left of Figure 4, respectively.…”

“…In this study, the calibrated and validated model was adopted from a previous study [14]. The calibrated parameters were directly used during the simulation of the SWAT model without the consideration of the soil and water conservation structures.…”

“…Hussain et al evaluated the soil erosion parameters and estimated the annual sediment loss in small watersheds of the Dhrabi River using the Soil and Water Assessment Tool (SWAT) model. The annual sediment yield ranged from 2.6 to 31.1 t hm −2 for the non-terraced catchments, while it ranged from 0.52 to 10.10 t hm −2 for the terraced catchments [14]. Iqbal et al studied runoff plots in the Dhrabi watershed in Chakwal Pakistan; cultivated slopes produced the highest soil loss (8.96 Mg ha −1 ) annually compared to both undisturbed gentle and steep slopes at approximately 2.08 and 4.66 Mg ha −1 [15].…”

“…The purpose of the study was to evaluate the effectiveness of soil and water conservation structure for soil erosion control using the SWAT model. The calibrated and validated model related to soil erosion was adopted from Hussain et al [14], where an experimental setup was used to monitor the soil and water loss from agricultural catchment. The collected data were used to calibrate and validate soil erosion parameters using the SWAT model.…”