Water availability shapes edaphic and lithic cyanobacterial communities in the Atacama Desert

Ca-Sulfates (Gypsum and Anhydrite) are the most common salts accumulating in the soil of the Chilean Atacama Desert. Sulfate sources include sea spray, redeposition of playa sediments, terrestrial weathering, and deposition of sulfate formed in the atmosphere (secondary atmospheric sulfate = SAS). Sulfate from sea spray, playa lakes, and terrestrial weathering have a triple oxygen isotope composition (&#916;17OSO4) at or slightly below zero reflecting reaction with water and oxygen. Positive &#916;17OSO4 are generally the result of atmospheric SO2 oxidation by ozone or hydrogen peroxide. Sulfate oxygen is only altered with ambient water by cycling through biological activity resulting in &#916;17OSO4 &#8776; 0&#8240;. Therefore, &#916;17OSO4 aids in quantifying the relative contribution of SAS to the desert soil and in identifying bioactivity and water availability in the hyperarid Atacama Desert. The spatial quantification of different sulfate sources may serve to improve the understanding of sulfate deposition in this region.Samples were analysed by continuous flow IRMS using the pyrolysis of Ag2SO4 to determine &#916;17OSO4 from O2. An optimized sample preparation to form clean silver sulfate and intra-day calibration against two in-house standards resulted in an external reproducibility of 0.12&#8240;. An inter laboratory comparison including data derived from the laser-fluorination method confirmed the accuracy of our analyses.We analyzed desert soil surface samples from four E-W transects in the Atacama Desert reaching from the Pacific coast across the Coastal Cordillera, the Central Depression, and up the alluvial fans protruding from the Pre-Andean Cordillera. Transects begin at Pisagua (19.5&#176;S), Salar Grande (21.0&#176;S), Antofagasta (24.0&#176;S), and Paposo (25.0&#176;S). Values of &#916;17OSO4 vary between 0.3 and 1.1&#8240;. The lowest &#916;17OSO4 values were measured near Salar Grande and on the Pre-Andean alluvial fans. The highest &#916;17OSO4 values are observed at the highest altitudes in the Coastal Cordillera - east of Paposo - well above the coastal fog zone (> 1200 m). At similar or higher altitudes on the Pre-Andean fans, &#916;17OSO4 converge towards zero.The spatial distribution is the result of source contributions and subsequent biological reset. Positive &#916;17OSO4 values throughout suggest a significant contribution from SAS. We quantified sea spray contributions using Cl-&#160;concentration, which drop dramatically above the fog-zone [1]. Furthermore, salt distribution suggests minimal weathering and redistribution in recent times. The lowest contribution from such near zero &#916;17OSO4 sulfate sources are expected in the Coastal Cordillera, which is consistent with our data. Within the Coastal Cordillera there is a north to south &#916;17OSO4 trend, which is also an elevation trend. Increased water availability from fog at lower elevations facilitates more efficient resetting of &#916;17OSO4 via microbial activity. These observations suggest that the driest place in the Atacama Desert is situated within the Coastal Cordillera above the fog zone.[1] Voigt et al. (2020) Global and Planetary Change 184

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Growth and early seedling survival of four Atacama Desert shrub species under experimental light and water availability regimes

Revista chilena de historia natural ◽

10.1186/s40693-014-0028-9 ◽

2014 ◽

Vol 87 (1) ◽

Cited By ~ 8

Author(s):

Danny E Carvajal ◽

Andrea P Loayza ◽

Ramiro P López ◽

Pablo J Toro ◽

Francisco A Squeo

Keyword(s):

Water Availability ◽

Seedling Survival ◽

Atacama Desert ◽

Shrub Species ◽

Desert Shrub ◽

Early Seedling

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Variation in δ15N of fog-dependent Tillandsia ecosystems reflect water availability across climate gradients in the hyperarid Atacama Desert

Global and Planetary Change ◽

10.1016/j.gloplacha.2019.103029 ◽

2019 ◽

Vol 183 ◽

pp. 103029 ◽

Cited By ~ 5

Author(s):

Andrea Jaeschke ◽

Christoph Böhm ◽

Felix F. Merklinger ◽

Stefano M. Bernasconi ◽

Mark Reyers ◽

...

Keyword(s):

Water Availability ◽

Atacama Desert ◽

Climate Gradients

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Functional analysis of the archaea, bacteria, and viruses from a halite endolithic microbial community

10.1101/029934 ◽

2015 ◽

Cited By ~ 2

Author(s):

Alexander Crits-Christoph ◽

Diego R Gelsinger ◽

Bing Ma ◽

Jacek Wierzchos ◽

Jacques Ravel ◽

...

Keyword(s):

Functional Analysis ◽

Microbial Community ◽

Water Availability ◽

Viral Genome ◽

Co2 Fixation ◽

Genome Structure ◽

Atacama Desert ◽

Autotrophic Co2 Fixation ◽

Microbial Ecosystems ◽

Osmotic Balance

Halite endoliths in the Atacama Desert represent one of the most extreme microbial ecosystems on Earth. Here we sequenced and characterized a shotgun metagenome from halite nodules collected in Salar Grande, Chile. The community is dominated by archaea and functional analysis attributed most of the autotrophic CO2 fixation to a unique cyanobacterium. The assembled 1.1 Mbp genome of a novel nanohaloarchaeon, Candidatus Nanopetramus SG9, revealed a photoheterotrophic life style and a low median isoelectric point (pI) for all predicted proteins, suggesting a "salt-in" strategy for osmotic balance. Predicted proteins of the algae identified in the community also had pI distributions similar to "salt-in" strategists. The Nanopetramus genome contained a unique CRISPR/Cas system with a spacer that matched a partial viral genome from the metagenome. A combination of reference-independent methods identified over 30 complete or near complete viral or proviral genomes with diverse genome structure, genome size, gene content, and hosts. Putative hosts included Halobacteriaceae, Nanohaloarchaea, and Cyanobacteria. Despite the dependence of the halite community on deliquescence for liquid water availability, this study exposed an ecosystem spanning three phylogenetic domains, containing a large diversity of viruses, and a predominant salt-in strategy to balance the high osmotic pressure of the environment.

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Biotechnological Applications Derived from Microorganisms of the Atacama Desert

BioMed Research International ◽

10.1155/2014/909312 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 11

Author(s):

Armando Azua-Bustos ◽

Carlos González-Silva

Keyword(s):

Water Availability ◽

High Salinity ◽

Atacama Desert ◽

Biotechnological Applications ◽

Analog Model ◽

The Past ◽

Basic Understanding ◽

Domains Of Life ◽

Immense Potential

The Atacama Desert in Chile is well known for being the driest and oldest desert on Earth. For these same reasons, it is also considered a good analog model of the planet Mars. Only a few decades ago, it was thought that this was a sterile place, but in the past years fascinating adaptations have been reported in the members of the three domains of life: low water availability, high UV radiation, high salinity, and other environmental stresses. However, the biotechnological applications derived from the basic understanding and characterization of these species, with the notable exception of copper bioleaching, are still in its infancy, thus offering an immense potential for future development.

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Evaluating Alternative Water Allocation Strategies for Maximizing Returns to Irrigation for Wheat in the Texas Panhandle under Declining Water Availability

World Environmental and Water Resources Congress 2007 ◽

10.1061/40927(243)241 ◽

2007 ◽

Author(s):

W. Arden Colette ◽

Lai K. Almas

Keyword(s):

Water Availability ◽

Water Allocation ◽

Texas Panhandle ◽

Alternative Water ◽

Allocation Strategies

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Impact of water availability on winter wheat ( Triticum aestivum L.) yield characteristics

Agrokémia és Talajtan ◽

10.1556/agrokem.59.2010.1.18 ◽

2010 ◽

Vol 59 (1) ◽

pp. 151-156 ◽

Cited By ~ 2

Author(s):

H. Klupács ◽

Á. Tarnawa ◽

I. Balla ◽

M. Jolánkai

Keyword(s):

Winter Wheat ◽

Water Supply ◽

Water Availability ◽

Grain Quality ◽

Physiological Condition ◽

Triticum Aestivum L ◽

Annual Precipitation ◽

Average Depth ◽

Experimental Site ◽

Yield Quality

Water supply of crop plants is the most essential physiological condition influencing quality and quantity performance of grain yield. In a 12-year experimental series of winter wheat agronomic trials run at the Nagygombos experimental site (Hungary) the effect of water availability has been studied. The location represents the typical average lowland conditions of the country, the annual precipitation of the experimental site belonging to the 550–600 mm belt of the Northern edges of the Great Hungarian Plain, while the average depth of groundwater varies between 2 to 3 metres. Crop years with various precipitation patterns have had different impacts on crop yield quality and quantity. Yield figures were in positive correlation with annual precipitation in general. Water availability had diverse influence on quality manifestation. Good water supply has often resulted in poorer grain quality, especially wet gluten and Hagberg values have been affected by that. Drought reduced the amount of yield in general, but contributed to a better quality manifestation in some of the crop years.

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CRITICAL FACTORS OF WATER CONTENT FOR FISH STOCKS IN THE WATER RESERVOIRS OF KAZAKHSTAN

VESTNIK OF ASTRAKHAN STATE TECHNICAL UNIVERSITY SERIES FISHING INDUSTRY ◽

10.24143/2073-5529-2017-1-9-18 ◽

2017 ◽

pp. 9-18

Author(s):

Saule Zhangirovna Asylbekova ◽

Kuanysh Baibulatovich Isbekov ◽

Evgeniy Vyacheslavovich Kulikov

Keyword(s):

Water Content ◽

Water Level ◽

Water Availability ◽

Hydrological Regime ◽

Fishing Effort ◽

Water Reservoirs ◽

The Caspian Sea ◽

Annual Fish ◽

Commercial Fish ◽

Fish Stocks

The hydrological regime of water reservoirs in different years has a decisive impact on the abundance of commercial fish stocks and the quality of ichthyocenoses. In this connection in 2015-2016 there was conducted a retrospective analysis and ranking of hydrological regime impact on these factors. The paper gives evaluation of catches and fish stocks under different scenarios of water availability in the main fishing ponds of the Republic of Kazakhstan that give about 80% of the annual fish catch of the country (except the Caspian Sea). There were analyzed 2000 factors of hydrological regime (water level, annual discharge) and 1845 factors of fishing stocks (catches, abundance, fish biomass). The paper determines the critical characteristics of water availability for fish stocks. There have been proposed a number of administrative decisions and actions in case if water content would approach to the critical level. Among them: limitation of fish catches in the following year; widening zones restricted for fishing; intensification of safety measures of the fish young in residual ponds during arid periods; introduction of catch standards for a unit of fishing effort in low-water years, high-water years and years with normal water level in rivers.

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