Limnological characterization of the water, algae and mudresources used in Copahue Thermal Complex (Neuquén,Argentina)

FLORES MELO XIMENA; DE LA ROSA NADIA; BAFFICO GUSTAVO; TEMPORETTI PEDRO; WENZEL TERESA ; PEDROZO FERNANDO; DIAZ MÓNICA

ECOLOGÍA AUSTRAL

ASOCIACIÓN ARGENTINA DE ECOLOGÍA

Lugar: Buenos Aires; Año: 2021 vol. 31 p. 400 - 412

0327-5477

Wecarried out the physicochemical characterization of extreme environments ofacidic geothermalsprings of the Copahue Thermal Complex, and isolated andcultivated algae used for therapeutic andmedicinal purposes. Ecophysiologicalaspects, algal photosynthetic responses and potential toxicity ofsediments wereanalysed. At the 15 sampling sites (pH: 2.0-6.7, conductivity: 283-3230 µS/cm,temperature:22-60 °C), 11 Cyanobacteria species of a total of 24 algae wereidentifid. The species richness was low withtrue inhabitants of highly acidicwaters: Cyanidium caldarium, Euglena mutabilis, Chlamydomonasacidophila,Achnanthidiumminutissimum, and Eunotiaexigua, andcosmopolitan species of thermal springs: Mastigocladuslaminosus, LeptolyngbiaboryanaandPhormidiumtergestinum. All the species were well adapted to low lightlevels(15-55 µmol photon.m-2.s-1), and photosynthetic responses were similar tothose in comparable environments.pH and temperature were important factors inalgal distribution, and N:P relationship suggests that P is thelimitingnutrient for algal growth. Fractions controlling P availability in the mudswere those bound to organicmatter, and Fe/Al oxyhydroxides. Healingmuds have the ability to precipitate metals and would not be toxic.Cadmium andother potentially toxic metals were in very low concentrations and pose no riskforthe humanuse as healing muds and bathing.