A water yield model for small semiarid watersheds of India | |
| Author | Panda, Jogesh Chandra |
| Call Number | AIT Thesis no.WA-86-12 |
| Subject(s) | Watersheds--India Hydrologic models |
| Note | A thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | The problem of water scarcity poses a threat to crop production in the semiarid tropics of India. A physically based hydrological model for the small watersheds in the region would help the practicing hydrologists and engineers in evaluating various measures of water conservation and in adopting the most efficient one. The present study has been undertaken with a view to develop one such model, relatively simple in concept and with a reasonable data demand. The model integrates the processes such as infiltration, soil moisture r edistribution and evapotranspiration and predicts storm runoff, soil moisture storage, evapotranspiration and deep percolation on a daily basis. The infiltration from unsteady rainfall is computed by using Green-Ampt-Mein-Larson equations in a procedure similar to Chu ' s . Finite difference techniques are used to solve the Richard's equation for one dimensional soil water flow. The sink term in the Richard's equation is computed from Refsgaard's model for evapotranspiration with some minor modifications. The model is validated against the measured runoff and soil moisture data from two watersheds under two extremes of land use. Close agreement between the measured and predicted values is found in all cases except the first runoff event in the early part of the season in all years which is attributed to soil cracking. A sensitivity analysis is done to investigate the relative importance of the model parameters in the simulation process. By virtue of its physical basis, the model finds a possible wide range of application besides the prediction of surface water yield. It can be used for scheduling irrigation, estimating natural recharge to ground water, determining effective rainfall and evaluating the impact of land use changes on the water yield of a watershed. |
| Year | 1986 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Water Resources Research Engineering (WA) |
| Chairperson(s) | Nielsen, Steen Asger |
| Examination Committee(s) | Gupta, Ashim Das |
| Scholarship Donor(s) | Canadian International Development Agency (CIDA) |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1986 |