Cholesteatoma and mastoid surgery. Edited by J. Sadé, 623 pp, illus, Kugler Publications BV, Amsterdam, The Netherlands, 1982. $95.00

Compositional Changes in Sediment Microbiota Are Associated with Seasonal Variation of the Water Column in High-Altitude Hyperarid Andean Lake Systems

“…All of the above generate different ecological configurations, such as areas with greater water column persistence and others with important annual oscillations, resulting in temporary aquatic systems ( 6 – 8 ).…”

“…They are made of a main body of water of a permanent nature; and different temporary sub-bodies, which can dry out depending on the season and rainfall regime. Consequently, the water column and sediment exposure present a high degree of annual and interannual variability ( 4 , 6 – 8 ).…”

“…The La Brava and La Punta lacustrine systems, located in the Tilopozo sector in the extreme south of the Salar de Atacama, are high-altitude Andean lakes (HAALs) along the central Andes of South America ( 2 , 3 ). Seasonal and long-term variations in precipitation and evaporation, among other natural factors, generate changes in the behavioral dynamics of the water column in La Brava and La Punta lakes ( 4 , 5 ), developing areas with greater persistence over time, as well as others with retreat or disappearance during the dry season, called temporary waters ( 6 – 8 ). These dynamics causes physicochemical changes in the water column and superficial sediments, such as low nutrient availability ( 3 ), pH change ( 9 ), dissolved metals ( 10 , 11 ), and other factors that can influence the composition and species richness of the microbiota ( 12 , 13 ).…”