干旱区生态环境知识资源中心(Arid): Geochemical proxies for water-soil interactions in the hyperarid Atacama Desert, Chile

Arid

DOI	10.1016/j.catena.2021.105531
	Geochemical proxies for water-soil interactions in the hyperarid Atacama Desert, Chile
	Arens, Felix L.; Airo, Alessandro; Feige, Jenny; Sager, Christof; Wiechert, Uwe; Schulze-Makuch, Dirk
通讯作者	Arens, FL (corresponding author), Tech Univ Berlin, Ctr Astron & Astrophys, D-10623 Berlin, Germany.
来源期刊	CATENA
ISSN	0341-8162
EISSN	1872-6887
出版年	2021
卷号	206
英文摘要	The Atacama Desert is the oldest and driest non-polar desert on Earth. Millions of years of hyperaridity enabled salt accumulations through atmospheric deposition. These salts can serve as proxies to decipher the interaction between water and soil as well as to understand the habitability with changing environmental settings. Therefore, we investigated four soil profiles regarding their mineralogy, salt abundance, and sulfate stable isotopic composition. The profiles were located along an elevation transect in the hyperarid region southeast of Antofagasta, Chile. The two lower sites situated on the distal parts of inactive alluvial fan deposits were subject to occasional fog occurrences. The upper steeper-sloped sites experienced no fog but are subject to minimal erosion. In all soil profiles, sulfates are the dominant salts showing a downward transition from gypsum to anhydrite that is accompanied by an increase of highly soluble salts and a decrease of sulfate delta S-34 and delta O-18 values. These trends are consistent with downward directed water infiltration during rare rain events causing salt dissolution followed by precipitation within the deeper soil column. This conclusion is also supported by our Rayleigh fractionation model. We attribute the presence of anhydrite at > 40 cm depth to the cooccurrence of nitrate and chloride salts, which decreases water activity during sulfate precipitation and therefore drives anhydrite formation. Along the elevation transect, the total salt inventories of each profile show a trend for nitrates and chlorides concentration decreasing with elevation. This observation together with the sulfate stable isotopes indicates a fog-independent source and suggests remobilization of soluble salts through enhanced washout from hillslopes to alluvial fans. These findings are essential for assessing the long-term regional habitability of hyperarid environments and have also relevance for Mars.
英文关键词	Gypsum Anhydrite Stable isotopes Pedogenesis Hyperarid Atacama Desert
类型	Article
语种	英语
开放获取类型	Green Accepted
收录类别	SCI-E
WOS记录号	WOS:000688449100040
WOS关键词	ZEBRA STRIPES ; GYPSUM ; SULFATE ; ANHYDRITE ; BASSANITE ; CA ; FRACTIONATION ; MECHANISM ; CLIMATE ; NITRATE
WOS类目	Geosciences, Multidisciplinary ; Soil Science ; Water Resources
WOS研究方向	Geology ; Agriculture ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/362801
作者单位	[Arens, Felix L.; Airo, Alessandro; Feige, Jenny; Sager, Christof; Schulze-Makuch, Dirk] Tech Univ Berlin, Ctr Astron & Astrophys, D-10623 Berlin, Germany; [Wiechert, Uwe] Free Univ Berlin, Dept Geochem, D-12249 Berlin, Germany; [Schulze-Makuch, Dirk] German Res Ctr Geosci GFZ, Sect Geomicrobiol, D-14473 Potsdam, Germany; [Schulze-Makuch, Dirk] Leibniz Inst Freshwater Ecol & Inland Fisheries I, Dept Expt Limnol, D-12587 Stechlin, Germany
推荐引用方式 GB/T 7714	Arens, Felix L.,Airo, Alessandro,Feige, Jenny,et al. Geochemical proxies for water-soil interactions in the hyperarid Atacama Desert, Chile[J],2021,206.
APA	Arens, Felix L.,Airo, Alessandro,Feige, Jenny,Sager, Christof,Wiechert, Uwe,&Schulze-Makuch, Dirk.(2021).Geochemical proxies for water-soil interactions in the hyperarid Atacama Desert, Chile.CATENA,206.
MLA	Arens, Felix L.,et al."Geochemical proxies for water-soil interactions in the hyperarid Atacama Desert, Chile".CATENA 206(2021).