Print Email Facebook Twitter The influence of flow-through saline gravel pit lakes on the hydrologic budget and hydrochemistry of a Mediterranean drainage basin Title The influence of flow-through saline gravel pit lakes on the hydrologic budget and hydrochemistry of a Mediterranean drainage basin Author Mollema, P.N. (TU Delft Geo-engineering; University of Bologna) Antonellini, Marco (University of Bologna) Dinelli, Enrico (University of Bologna) Greggio, Nicolas (University of Bologna) Stuyfzand, Pieter Jan (TU Delft Geo-engineering; KWR Water Research Institute) Date 2015 Abstract Flow-through brackish gravel pit lakes near the Adriatic Coast of Emilia Romagna (Italy) in the Mediterranean have a large influence on the hydrologic budget of the watershed. Strong evaporation in combination with intense drainage of the low lying basins enhances groundwater inflow into the lake. Precipitation falling on the lakes is mixed with brackish/saline lake water causing the loss of freshwater. The gravel pit lakes are characterized by a high salinity (TDS = 4.6-12.3 g L"1) and high pH (8.5). Stable isotope data show that gravel pit lake water is fed by groundwater which is a mix of Apennine River water and (Holocene) Adriatic Seawater, subsequently enriched by evaporation. The slope of the local evaporation line is 5.4. Conservative tracer and water budget modeling shows that the final Cl concentration depends strongly on the ratio of evaporation to total inflow. Increasing drainage to compensate for sea level rise, subsidence or intense precipitation would enhance ground water flow into the lake and decrease Cl concentration while increasing evaporation would increase Cl concentration. Groundwater rich in dissolved trace elements flows into the gravel pit lakes that contains water with a higher pH and dissolved oxygen. Pit lake water remains enriched in some elements (e.g., Ba, Mo, Sb) and depleted in others (e.g., Fe, Ca, Zn, SO4) with respect to groundwater composition. The gravel pit lakes show limited eutrophication but the water quality should be monitored for trace elements (e.g., As) if they are to be used for recreational purposes. To reference this document use: http://resolver.tudelft.nl/uuid:b6d46637-85b8-4d7c-93cc-2d19fedac741 DOI https://doi.org/10.1002/lno.10147 ISSN 0024-3590 Source Limnology and Oceanography, 60 (6), 2009-2025 Part of collection Institutional Repository Document type journal article Rights © 2015 P.N. Mollema, Marco Antonellini, Enrico Dinelli, Nicolas Greggio, Pieter Jan Stuyfzand Files PDF Mollema_et_al_2015_Limnol ... graphy.pdf 899.06 KB Close viewer /islandora/object/uuid:b6d46637-85b8-4d7c-93cc-2d19fedac741/datastream/OBJ/view