Impact of Future Land-Use/Cover Change on Streamflow and Sediment Load in the Be River Basin, Vietnam

Abstract

Evaluation of the influence of land-use/cover (LUC) change on water and sediment fluxes from river basins is essential for proposing adaptation and mitigation strategies, but as of yet little information is available, especially in the tropics. For this motivation, the objective of this study was to assess the impact of scenarios of LUC change on streamflow and sediment load in the Be River Basin using the Dynamic Conversion of Land-Use and its Effects (Dyna-CLUE) model and the Soil and Water Assessment Tool (SWAT) model. The Dyna-CLUE and SWAT models were calibrated and validated against observed data in the period of 1980–2010. Three future LUC scenarios in 2030, 2050, and 2070 were generated utilizing the calibrated Dyna-CLUE model based on the historical conversion of forest land to agricultural land and urban area in the study region. Subsequently, the calibrated SWAT model was used to simulate the changes in streamflow and sediment load under these three future LUC scenarios. Results indicated that the annual streamflow and sediment load were estimated to be approximately 287.35 m3/s and 101.23 × 103 ton/month for the baseline period. Under the influence of future LUC scenarios, the annual streamflow and sediment load would experience increases of 0.19% to 0.45% and 0.22% to 0.68%, respectively. In addition, the 5th and 95th percentile values of streamflow and sediment load are predicted to rise in the context of future LUC change. The results achieved from the present study will support the managers and policy makers proposing appropriate solutions for sustainable water resources management and sediment control in the context of LUC change.