Dalangtan Playa (Qaidam Basin, NW China): Its microbial life and physicochemical characteristics and their astrobiological implications

• DOI: 10.1371/journal.pone.0200949
• Publication Date: 2018-08-01T17:37:47Z
• Authors: Ting Huang; Ruicheng Wang; Long Xiao; Hongmei Wang; José M. Martínez; Cristina Escudero; Ricardo Amils; Ziye Cheng; Yi Xu
• Keywords: Salt pan; Life on Mars

Dalangtan Playa is the second largest salt playa in Qaidam Basin, north-western China. The hyper saline deposition, extremely arid climate and high UV radiation make a Mars analogue both for geomorphology life preservation. To better understand microbial at Dalangtan, culture-dependent culture-independent methods were examined simultaneously, environment conditions evaporitic mineral assemblages investigated. Ten thirteen subsurface samples collected along 595-cm deep profile (P1) 685-cm (P2) respectively, seven gathered from surface sediments. These are composed of minerals, minor silicate fragments clays. total bacterial cell numbers (1.54±0.49) ×105 g−1 P1 (3.22±0.95) P2 as indicated by CAtalyzed Reporter Deposition- Fluorescent situ Hybridization (CARD-FISH). 76.6% 75.7% bacteria belong to Firmicutes phylum respectively P2. In total, 47 6 fungi isolated 22 samples. contrast, only 3 1 fungus show homology (≥97%) with members (47 strains, 8 genera) Actinobacteria (3 2 genera), which agrees result CARD-FISH. Isolated showed ≥98% ITS1 Ascomycota. Moisture content TOC values may control sediments colonization. Given deliquescence salts, evaporites provide refuge life, merits further investigation. Halotolerant spore-forming microorganisms dominant groups capable surviving under extreme conditions. Our results offer brand-new information on biomass shed light understanding potential dried or paleo-lakes Mars.