Extremeophiles and Extreme Environments

Ecophysiological Study Of Green Microalgae Isolated From The Grit Crust Of The Atacama Desert

By Keith Cowing

Status Report

Journal of Phycology via PubMed

June 25, 2026

Filed under Atacama Desert, Away Team, biocrust, desert, desert planet, extreme environment, extremophile, Green Microalgae, Grit Crust, Journal of Phycology, Klebsormidium elegans, Lobosphaera incisa, microecosystem, National Park Pan de Azúcar, Pseudochlorella signiensis, Sample Return

Ecophysiological Study Of Green Microalgae Isolated From The Grit Crust Of The Atacama Desert — Vivid colors belie the arid landscape of northern Chile where the Atacama Desert,one of the world’s driest, meets the foothills of the Andes. Here salt pans andgorges choked with mineral-streaked sediments give way to white-capped volcanoes. This scene was acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA’sTerra satellite on October 28, 2001. Image provided by the USGS EROS Data Center Satellite Systems Branch as part of the Earth as Art II image series. Larger image

Terrestrial algae play a critical, yet often overlooked, role in the functioning of biological soil crusts (biocrusts), which are considered microecosystems, particularly in extreme environments.

This study investigated the ecophysiological traits of green algae isolated from the grit crust—a unique biocrust type reported a few years ago in the coastal Atacama Desert (National Park Pan de Azúcar), Chile.

We assessed photosynthetic performance, temperature tolerance, and desiccation recovery in four strains: Pseudochlorella signiensis strain C11, Lobosphaera incisa strain LC2, and two strains of Klebsormidium elegans, C12 and C14. The results revealed significant interspecific variation, with P. signiensis exhibiting the highest photosynthetic capacity and both Klebsormidium strains demonstrating efficient light utilization.

Desiccation recovery at very low relative air humidity was limited across all species, potentially reflecting the influence of frequent fog events in the coastal region of the Atacama, which result in a moderate air humidity.

This study fills a critical knowledge gap regarding terrestrial algal ecology in South America and highlights the physiological traits enabling algal survival in one of the world’s most extreme environments, providing insights into the resilience of biocrust communities in the face of environmental change.

Micrographs of the isolated green algae. (a–c) Klebsormidium elegans C12, (d, e) Klebsormidium elegans C14, (g–i) Pseudochlorella signiensis C11, (j–l) Lobosphaera incisa LC2. — Journal of Phycology

Ecophysiological study of green microalgae isolated from the grit crust of the Atacama Desert, Journal of Phycology via PubMed
Ecophysiological study of green microalgae isolated from the grit crust of the Atacama Desert, Journal of Phycology (open access)

Astrobiology, extremophile,

Keith Cowing

Biologist, Explorers Club Fellow, ex-NASA Space Biologist and Payload integrator, Editor of NASAWatch.com and Astrobiology.com, Lapsed climber, Explorer, Synaesthete, Former Challenger Center board member 🖖🏻

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