University of Twente Student Theses
Simulation of groundwater recharge in the Sardon catchment, Spain
Cisneros, César (2011) Simulation of groundwater recharge in the Sardon catchment, Spain.
|
PDF
3MB |
| Abstract: | Diverse techniques are available to quantify ground water recharge in the semi arid catchment of Sardon River. Methods as chloride mass balance or numerical models that solve Richard´s equations have been implemented. However, since assessment of groundwater recharge is an iterative process that comprises refinement of estimates as additional data are gathered, a different approach using INFIL3.0, a distributed water-balance model for the unsaturated zone, has been applied in order to estimate groundwater recharge. Computer code of INFIL3.0 developed for semiarid areas has been adapted to the data availability of Sardon Catchment. Meteorological information, thematic maps and field observations are processed using GIS techniques to use as input for the model. Due to the absence of streamflow data for calibration, evaluation of the model by comparing values of evapotranspiration calculated at the eddy tower and comparing the trend of soil moisture in a soil profile are proposed as surrogate. For the period 2007-2008, with an average precipitation of 515 mm/year, the average annual ground water recharge estimated in the simulation is 72mm/year. This value is equivalent to 14% RF (percentage of rainfall). The spatial distribution showed higher groundwater recharge values located over stream channels and close to outcrops >40%RF and very low groundwater recharge values for areas close to massive and fractured granite. The results of previous studies are: for steady state modelling MODFLOW 11%RF (Lubczynski and Gurwin, 2005) and 12%RF (Ruwan Rajapakse, 2009); those averaged from simulations with pyEarth1D 20%RF (Ruwan Rajapakse, 2009) and Earth1D 18%RF (Uria Cornejo, 2000); and averaged values obtained by Chloride mass balance method 10.5%RF (Ruwan Rajapakse, 2009). These values show a similarity compared to the present study results. Despite these values of recharge are numerically comparables with those obtained from other methods as chloride mass balance and pyEarth1D, calibration and configuration of surface routing parameters are suggested in order to increase the confidence of these results. Keywords: Sardon, model, groundwater, recharge, INFIL, semi ari |
| Item Type: | Essay (Master) |
| Faculty: | ITC: Faculty of Geo-information Science and Earth Observation |
| Programme: | Geoinformation Science and Earth Observation MSc (75014) |
| Link to this item: | https://purl.utwente.nl/essays/93404 |
| Export this item as: | BibTeX EndNote HTML Citation Reference Manager |
Show download statistics for this publication
Show download statistics for this publicationRepository Staff Only: item control page