The ecological and socioeconomic importance of mountains is being increasingly recognised. Such
regions provide key ecosystem services, namely, water supply which benefits local as well as lowland
human populations. Besides mountain aqui fers and rivers, alpine lakes and ponds are crucial for water
resources management but are also important in hydroecological and wildli fe conservation terms. This
study aims at comparing the pollution of surface and underground water bodies by de -icing chemicals
in a mountain environment. The influence of geological, geomorphological, pedological, climatic and
anthropic conditions is taken into account. The study region is the highest part of the Serra da Estrela,
a Mediterranean mountain located in Central Portugal. In this area there is a hydrological system
which encompasses water-table aquifers and number of alpine ponds of glacial origin situated
between 1500 m a.s.l. and the summit (1993 m a.s.l.). In the study area, the alpine ponds and springs
were inventoried. Water sampling campaigns were carried out for hydrogeochemical characterisation
of alpine ponds. These results were compared with hydrogeochemical data from water springs
obtained in previous studies. Concentration of the following analytes were determined- total organic
carbon (TOC), metals (Pb, Zn, Fe, Cu, Ni, Cd, Cr, As, Mn), cations (Na+, K+, Ca2+, Mg2+), anions (F-,
CI-, NO3-, SO42-), silica (SiO2) and nutrients (N, P). Additionally, parameters such as pH, conductivity,
turbidity and alkalinity were also measured. The hydrogeochemistry of ponds and water table aqui fers
affected by de-icing chemicals is clearly different from the one showed by non-polluted water bodies,
due to the influence of different physical settings as well as to the spatial distribution of the anthropic
influence. The pond and aqui fer contamination affects water quality but may also disturb the local
highly sensitive aquatic ecosystems.N/
