Revista Chilena de Historia Natural 81 (4): 469-488, 2008
RESEARCH ARTICLE
Importance of water quality on plant abundance and diversity in high-alpine meadows of the
Yerba Loca Natural Sanctuary at the Andes of north-central Chile
Porphyry Cu-Mo deposits have influenced surface water quality in high-Andes of north
central Chile since the Miocene. Water anomalies may reduce species abundance and diversity in alpine meadows as acidic and
metal-rich waters are highly toxic to plants The study assessed the importance of surface water quality on plant abundance and
diversity in high-alpine meadows at the Yerba Loca Natural Santuary (YLNS), central Chile (33º15’ S, 70º18’ W). Hydrochemical and
plant prospecting were carried out on Piedra Carvajal, Chorrillos del Plomo and La Lata meadows the growing seasons of 2006 and
2007. Direct gradient analysis was performed through canonical correspondence analysis (CCA) to look for relationships among water
chemistry and plant factors. High variability in water chemistry was found inside and among meadows, particularly for pH, sulphate,
electric conductivity, hardness, and total dissolved Cu, Zn, Cd, Pb and Fe. Data on species abundance and water chemical factors
suggests that pH and total dissolved Cu are very important factor determining changes in plant abundance and diversity in study
meadows. For instance, Festuca purpurascens, Colobanthus quitensis, and Arenaria rivularis
are abundant in habitats with Cu-rich waters while Festuca magellanica, Patosia clandestina,
Plantago barbata, Werneria pygmea, and Erigeron andicola are abundant in habitats with dilute
waters.
Key words:
porphyry deposits,
phytotoxicity, plant diversity, acid mine drainage, copper toxicity
