Hydrochemistry of Lakes of the Patagonian Province of Tierra del Fuego (Argentina)

Abstract

Chemical studies on 19 lakes of the Argentine sector of the Patagonian Tierra del Fuego Island were performed. These lakes are placed in two geological provinces, Extra Andine (northern) and Fueguian Cordillera (southern). Range of the results obtained, pH (5.80-8.60), TDS (29.5-10,232 mg/l), ionic composition (from calcium bicarbonate to sodium chloride type), Secchi disc depth (0.05-12 m), total inorganic nitrogen (20-237 ug N/l), orthophosphate (5-498 ug P/l), total phosphorus (5-3,800 ug P/l) and clorophyll a (0.1-63.0 ug/l), indicated the presence of a wide variety of aquatic ecosystems. According to Gibbs model, the mechanisms that control the water chemistry are mainly rock dominance and evaporation-crystallization processes.