Impacts of climate change and land use change on hydrology in Transboundary River Basin : a case study in 3S (Sekong, Sesan, Srepok) river basin | |
| Author | Mahajan, Nisha |
| Call Number | AIT Thesis no.WM-16-32 |
| Subject(s) | Climatic change Land use |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. WM-16-32 |
| Abstract | Climate change has become the critical issue in this today's world. This research focused on the analysis of climate change and land use change impact on the streamflow of 3S - Sekong, Sesan, Srepok river basin. The GIS based hydrological model Soil and Water Assessment tool (SWAT) was carried out to determine the streamflow in this basin. This transboundary river basin plays the vital role in socio - economic development of the host countries Lao PDR , Vietnam and Cambodia. The prediction of future climate up to the end of 2100 was done using CCSM4, MRI - CGCM3, Can ESM 2, MIROC 5, MIR OC - ESM, MIROC - ESM - CHEM, BCC - CSM 1.1 and GISS - E2 - R - XX under representative concentration pathways (RCP) 4.5 and 8.5 scenarios. The bias correction of GCM data was carried out using the quantile mapping. The minimum temperature is predicted to increase by 4. 579 ° C , maximum temperature by 2.892 ° C and precipitation by 1 8.82 % at the end of this century. The highest increase in median value of minimum temperature of 0.38% as predicted by MIROC - ESM - CHEM and 0.14% increase in maximum temperature by 2080s under RCP 8 .5 scenario. The flatter shape of Probability Density Function (PDF) of temperature indicates that coolest year during this period are going to be hotter than hottest year of baseline period. The increase of median value up to 0.39% in annual mean precipitation is expected to occur in 2080s under RCP 4.5 scenario. The uncertainty is found to increase in future with flatter probability density function with respect to time. The simulation of the streamflow was carried out with the hydrological model SWAT with R 2 , NSE , PBIAS as 0.70, 0.69 and 4.74% and 0.76, 0.74, 0.50% respectively for t he basin outlet during calibration (1985 - 2000) and validation period (2001 - 2005) respectively. The annual streamflow is predicted to increase by 15.61 % in 2030s, 23.83% in 2050 s and 19.12 % in 2080s under RCP 4.5 scenario and by 17.14 %, 41.14 % and 26.25 % in 2030s, 2050s and 2080s respectively under RCP 8.5 scenario . The annual streamflow is predicted to decrease by 0.37%, 1.14% and 1.22% in 2030s, 2050s and 2080s with increase in evapotranspiration under conversion of agriculture to forest land at 1% per year (AF1) scenario while in other case result is increase d in streamflow by 0.37% in 2030s to 9.69% in 2080s. Again it is predicted that the conversion of forest land to agricultural land at 1% per year (FA1) and climate change has overall high increase in streamflow range from 14% to 25% in 2030s to 2080s. But the maximum increase in streamflow is predicted by 30.41% under RCP 8.5 in 2050s while less increase of 7.45% under RCP 4 .5 in 2080s under conversion of forest to grassland at 1% per year (FG1) scenario and climate change. Hence, the change in climate has significant impact on hydrology than land use change only . The shifting of PDF of discharge to right from the baseline PD F shows that the streamflow is increasing in low flow period and high flow period. The flatter PDF represented by some GCM prediction and adopted land use change scenario shows the higher uncertainty in projection of future discharge due to uncertainty observed in climate projection. This analysis explains that the projected stream flow increase low in low flow period and higher in wet season. |
| Year | 2016 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. WM-16-32 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Shrestha, Sangam |
| Examination Committee(s) | Shrestha, Rajendra Prasad;Jayakumar Ramasamy |
| Scholarship Donor(s) | AIT Fellowship |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2016 |