Hydrological simulation of a typical basin in central Vietnam under different land use scenarios

• Main Author: Pham, Xuan Hoa
• Format: Thesis
• Language: English
• Published: Universiti Malaysia Sarawak, (UNIMAS) 2004
• Subjects: GE Environmental Sciences
• Online Access: http://ir.unimas.my/id/eprint/12608/1/Pham%20Xuan%20Hoa%20ft.pdf; http://ir.unimas.my/id/eprint/12608/

Changes in the land use and land cover in the Krong Buk basin had adversely affected the annual water resources in the region and hence, the optimal agricultural and human development of the basin had been hampered. The objective of this study is to apply the public domain semi-distributed rainfall-runoff model (HEC-HMS) to predict the impact of changes in the land use and land cover on the total outflow from the Krong Buk basin due to some particular rainfall events., The public domain Geo-HMS pre-processor was used as a modelling tool. Input data were the Digital Elevation Model, land use map, hydrological soil group map, daily rainfall and flow data. Calibration and validation of the model were carried out both by choosing the parameter that give the best fit to the model and by means of the Nash objective function with good results (80%). Subsequently, the model was applied under two different scenarios. That is the replacement of the mixed area (which is at the upstream by the forested area due to reforestation) and the conversion of the forested area to planted crop(which is at the middle part of the basin into coffee area). Under the former, the flow peak was 19 m3/s and water volume was 174 mm for the year 1994. In the latter case, there was an increase in the flow peak by 13.28% and water volume by 13.39%. The study is expected to assist water use planners, decision-makers and stakeholders to manage better the available water resources within the Krong Buk basin by predicting the impact of storm runoff due to the land use in the basin.