Hydrology and Earth System Sciences Discussions www.hydrol-earth-syst-sci-discuss.net 1812-2108 1812-2116 6 2 2009 10.5194/hessd-6-3359-2009 http://www.hydrol-earth-syst-sci-discuss.net/6/3359/2009/ http://www.hydrol-earth-syst-sci-discuss.net/6/3359/2009/hessd-6-3359-2009.html http://www.hydrol-earth-syst-sci-discuss.net/6/3359/2009/hessd-6-3359-2009.pdf 3359 3384 2009-04-22 The hydrological response of baseflow in fractured mountain areas A. Millares mivalag@ugr.es M. J. Polo M. A. Losada Environmental Fluid Dynamic Group, Andalusian Centre for Environmental Studies (CEAMA), Avda. del Mediterráneo s/n, 18006, Granada, Spain Hydrology and Hydraulics in Agriculture Research Group, University of Córdoba, Campus de Rabanales, Edif. Leonardo da Vinci, 14071-Cordoba, Spain The study of baseflow in mountainous areas of basin headwaters, where the characteristics of the often fractured materials are very different to the standard issues concerning porous material applied in conventional hydrogeology, is an essential element in the characterization and quantification of water system resources. Their analysis through recession fragments provides information on the type of response of the sub-surface and subterranean systems and on the average relation between the storage and discharge of aquifers, starting from the joining of these fragments into a single curve, the Master Recession Curve (MRC). This paper presents the generation of the downward MRC over fragments selected after a preliminary analysis of the recession curves, using a hydrological model as the methodology for the identification and the characterization of quick sub-surface flows flowing through fractured materials. The hydrological calculation has identified recession fragments through surface runoff or snowmelt and those periods of intense evapotranspiration. The proposed methodology has been applied to three sub-basins belonging to a high altitude mountain basin in the Mediterranean area, with snow present every year, and their results were compared with those for the upward concatenation of the recession fragments. The results show the existence of two different responses, one quick (at the sub-surface, through the fractured material) and the other slow, with linear behavior which takes place in periods of 10 and 17 days, respectively and which is linked to the dimensions of the sub-basin. In addition, recesses belonging to the dry season have been selected in order to compare and validate the results corresponding to the study of recession fragments. The comparison, using these two methodologies, which differ in the time period selected, has allowed us to validate the results obtained for the slow flow. Aguilar, C.: Efectos de escala en procesos hidrológicos, Aplicación a la cuenca del río Guadalfeo, M. S. in Hydrology, University of Cordoba, 40–42, online available at: http://www.cuencaguadalfeo.com/archivos/DEA_Cristina_Aguilar.pdf 2006. Bako, M. D. and Hunt D. N.: Derivation of baseflow recession constant using computer and numerical analysis. Hydrol. Sci. J., 33(4), 357–367, 1988. Castillo, A., Cruz, J. J., and Benavente, J.: Aguas de Sierra Nevada; Aguas de Lanjarón. Lanjarón: paisajes del agua, Balneario de Lanjarón, SA Granada, 35–64, 1999. Castillo, A. and Fideli, B.: Algunas pautas del comportamiento hidrogeológico de rocas duras afectadas por glaciarismo y periglaciarismo en Sierra Nevada (España), Geogaceta, 32, 189–191, 2002. Chapman, T. G. and Maxwell, A.: Baseflow separation, Comparison of numerical methods with tracer experiments, Proceedings of the 23rd Hydrology and Water Resources Symposium, 539–545, 1996. Chapman, T. G.: Modeling stream recession flows, Environ. Modell. Softw., 18, 683–692, 2002. Coutagne, A.: Etude générale des variations de débits en fonction des fractures qui les conditionnent. 2ème partie: Les variations de débits en période non influencée par les précipitations, La Houille Blanche, 3, 416–436, 1948. Demuth, S.: Research basin studies, in: Flow Regimes from Experimental and Network Data (FREND), Institute of Hydrology, Wallingford, UK, 141–185, 1989. Fenicia, F., Savenije, H. H. G., Matgen, P., and Pfister L.: Is the groundwater reservoir linear? Learning from data in hydrological modeling, Hydrol. Earth Syst. Sc., 10, 139–150, 2006. Hall, F. R.: Baseflow recessions, a review, Water Resour. Res., 4(5), 973–983, 1968. Hamad, O. E.: Optimal operation of a reservoir system during a dry season, PhD thesis, University of Newcastle upon Tyne, 1, 227~pp., 1993. Hammond, H.: Recession curve estimation for storm event separations, J. Hydrol., 330, 573–585, 2006. Herrero, J.: Modelo físico de acumulación y fusión de la nieve, Aplicación en Sierra Nevada (España), PhD thesis, University of Granada, online available at: www.ugr.es/local/herrero, 2007. Herrero, J., Polo, M. J., Moñino, A., and Losada, M. A.: An energy balance snowmelt model in a Mediterranean site, J. Hydrol., doi:10.1016/j.jhydrol.2009.03.021, accepted, 2009. Hewlett, J. D.: Soil moisture as a source of baseflow from steep mountain watersheds, US For. Serv. Southeast. For. Exp. Stn., 132, USA, 1961. Lamb, R. and Beven, K.: Using interactive recession curve analysis to specify a general catchment storage model, Hydrol. Earth Syst. Sci., 1, 101–113, 1997. Linsley, R. K, Kohler, M. A., and Paulhus, J. L. H.: Hydrology for Engineers, McGraw-Hill, New York, USA, 1958. Millares, A.: Integración del caudal base en un modelo distribuido de cuenca, Estudio de las aportaciones subterráneas en ríos de montaña, PhD thesis, University of Granada, Spain, 2008. Millares, A., Aguilar, C., Herrero, J., Ávila, A., Moñino, A., Nieto, S., Vega, C., Polo, M. J., and Losada, M. A.: Proyecto Guadalfeo; Modelo de gestión Integral de Cuencas Mediterráneas, INTERREG IV MEDOCC, Agencia Andaluza del Agua, edited by: Polo, M. J. and Losada, M. A., online available at: http://www.cuencaguadalfeo.com/archivos/Resumen_Interreg.pdf, 2008. Smakhtin, V. Y.: Low flow hydrology: a review, J. Hydrol., 240, 147–186, 2001. Tallaksen, L. M.: Analysis of time variability in recessions, IAHS Publ., 187, 85–96, 1989. Tallaksen, L. M.: A review of baseflow recession analysis, J. Hydrol., 165, 349–370, 1995. Tóth, J.: A conceptual model of the groundwater regime and the hydrogeologic environment, J. Hydrol., 10, 164–176, 1970. Wittenberg, H.: Baseflow recession and recharge as nonlinear storage processes, Hydrol. Process., Special Issue Process Interactions in the Environment, 13(5), 715–726, 1999. Wittenberg, H. and Sivapalan, M.: Watershed groundwater balance estimation using stream-flow recession analysis and baseflow separation, J. Hydrol., 219, 20–33, 1999. Zecharias, B. and Brutsaert, W.: The influence of basin morphology on groundwater outflow, Water Resour. Res., 24, 1645–1650, 1988.