A generalized framework for modeling the hydrologic and biogeochemical response of a Mediterranean temporary river basin

SummaryA generalized framework for the integrated observational and modeling study of a typical Greek temporary river is presented. A karstic spring flow model was developed for the estimation of daily spring flows into the watershed from its extended karst area. The karstic model assumes the existence of an upper (faster) and a lower (slower) reservoir that represent the two different karstic formations of the region. The karstic spring flow model was coupled with a watershed model, the Hydrological Simulation Program – Fortran (HSPF) in order to simulate the hydrology, sediment transport and nutrient loads of Krathis river basin. Forty two percent of Krathis river flow was estimated to be from the contribution of the karstic springs. The combined models simulated the time response of the watershed based on geochemical and hydrologic mass balances. The seasonal variability of flow and the concentrations of suspended solids and nutrients was captured by the simulations. The karstic model was shown to be a useful tool for analyzing karstic systems by estimating the contributing area of the karst and its response to precipitation events. This framework can be used to simulate watersheds where karstic geologic formations predominate.