Limnetica 40

This paper describes the hydrology of Fuirosos a small intermittent stream draining a forested catchment located close to Barcelona (NE Iberian Peninsula) that has been intensively studied over the last 20 years. Discharge regime at Fuirosos is strongly related to the precipitation regime and showed, during the entire study period, a significant decrease, at a rate of -0.4 L/s/y which represents 1.3 % of the estimated average discharge. Further, drought duration is lengthening at a rate of 1.9 d/y, mainly as a consequence of delay of the rewetting phase. Overall, if these trends continue at their current rates, Fuirosos will be converted into an ephemeral stream during the second half of this century. Fuirosos is at the center of an intense research activity focused on the ecology of this aquatic ecosystem. Research topics range from measuring microbial processes in sand sediments to analyzing solute responses under extreme flow conditions (flood and droughts), including metabolism measurements, nutrient retention balances, macro-benthos diversity and leaf inputs in stream reaches or water/solute exchange at the stream-hyporheic interface. Most of these studies revealed that its ecology is related unequivocally to the hydrological regime. Accordingly, the second part of the present work summarizes and reviews these ecological and biogeochemical studies.