Changes in Land Use Affect Dependable Discharge in the Miu River Basin

Abstract

Land use changes in a watershed will affect to net rainfall and have an impact to river discharge. Evaluation of plant interception due to land use changes would had better view of net rainfall. The descriptive research is aims to determine changes in land use that affect net rainfall and reliable discharge using the Nreca calculation model. The area of the Miu watershed was 654. 55 km2 and the changes in land use was considered the years of 2005, 2010 and 2016 which is observed by using ArcGIS software to evaluate the catchments area. The land use changes show the forest area decrease from 82. 10% in 2005 to 78. 65 and 89. 67% for 2010 and 2016, but there has been a lot of increase in open area from 1. 71% in 2005 to 8. 19% in 2016. Net rainfall was applied in calculation of dependable discharge and the results obtained show the flow consistency. The input parameter for initial SMS is 200 mm, PSUB is 0. 85 and GWF is 0. 25. The average discharge obtained is 9. 15 m3/sec. The graph shows very close relationship between net rainfall that influencing to dependable discharge.