Drowning in a sandy ocean: Epiarenic growth of Tillandsia in the hyperarid Atacama Desert

作者：Robin Schweikert, Ron Eric Stein, Neil Bogs, Olaf Bubenzer, Camilo del Río, Dörte Harpke, Simon Matthias May, Alexander Siegmund, Alexandra Stoll, Dietmar Quandt, Мarcus A. Koch · 发表于：bioRxiv (Cold Spring Harbor Laboratory) · 年份：2026 · DOI：10.64898/2026.02.23.707457 · 被引用次数：1 · 研究领域：Biocrusts and Microbial Ecology、Fern and Epiphyte Biology、Aeolian processes and effects

Abstract The Atacama Desert hosts a unique ecosystem formed by the sand-dwelling Tillandsia landbeckii , which extends over hundreds of square kilometers. This vegetation relies primarily on fog as its main water source; however, aeolian sand also plays a crucial role in the long-term persistence of both the species and the overall plant community. The terrain is sloped and exposed to the prevailing wind direction. Tillandsia forms regular banding patterns oriented orthogonally to these landscape features. In this study, we aim to elucidate the abiotic–biotic interactions between sand properties and vegetation characteristics through a comparative approach. Three populations - Caldera, Oyarbide and Arica -, each spanning several square kilometers in the southern, central, and northern regions of the Chilean Atacama Desert, were selected to compare wind regimes, terrain structure, sand and substrate properties, and vegetation structure in order to identify common principles that maintain vegetation integrity. Data were collected from six climate stations, 1,246 substrate samples, population genomic data from 718 individuals, as well as satellite imagery and digital terrain models. Our findings demonstrate that regional wind systems transport sand from distant source areas, while near the ground, Tillandsia vegetation reduces wind velocity and traps sand, leading to the formation of moderately sorted sandy substrates that are similar across all three populations. Sites lacking ...