Integrated Watershed Management Using the SWAT Algorithm for Sediment and Nutrient Transport

Abstract

 To develop an effective watershed management strategy, it is important to understand how the processes 
of sediment transport and nutrient transport affect water quality and the balance of the ecosystem. This study uses the 
SWAT system (Soil and Water Assessment Tool), which is a semi-distributed and physically based hydrological 
model, to analyze and simulate the processes of sediment and nutrient transport for integrated watershed management 
practices. The SWAT model is able to predict runoff, erosion, and nutrient transport cycles based upon land 
characteristics and climatic factors as long as the appropriate land use patterns, topography, soil information, and 
climate data are spatially and temporally integrated. The model was calibrated and validated using existing hydrology 
and water quality datasets from a nearby adjacent watershed utilized for this study, and gave reasonable results where 
field data were available. The model then enabled simulations to identify critical source areas related to excessive 
sedimentation and nutrient loading; therefore, areas where implementing agricultural best management practices 
(BMPs) described in Section 5: buffer strips, reforestation, and precision fertilizer application would be desirable. 
This study emphasizes the need for developing and planning policies strategically guided by modelling tools as part 
of decision support systems used to inform regulations for sustainable land and water resources management and to 
protect and promote watershed resilience.