Water Quality and Microclimate Gradients in the Argentine Andes and Patagonia: Field Measurements of TDS, Conductivity, and Temperature Across Altitudes

This field study reports portable in situ measurements of water temperature, Total Dissolved Solids (TDS), electrical conductivity (EC), air temperature, and humidity across six representative sites in Argentina (March 2025). We sampled 20 points spanning 115 m (Perito Moreno) to 3 383 m (Aconcagua). Mean TDS at high‑altitude sites (Aconcagua: 1172 ± 425 ppm) was up to 50 times higher than at Patagonian lakes (Refugio Frey: 6 ± 1 ppm). A near‑perfect linear relationship (EC = 2.01 × TDS, R² = 0.995) validates field conductivity proxies. These novel baseline data reveal unexpectedly high mineralization in Andean meltwaters and underscore geological controls on freshwater chemistry in remote mountain ecosystems.