Hierarchical structures of cactus spines that aid in the directional movement of dew droplets.
Philos Trans A Math Phys Eng Sci
; 374(2073)2016 Aug 06.
Article
en En
| MEDLINE
| ID: mdl-27354735
Three species of cactus whose spines act as dew harvesters were chosen for this study: Copiapoa cinerea var. haseltoniana, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa and compared with Ferocactus wislizenii whose spines do not perform as dew harvesters. Time-lapse snapshots of C. cinerea showed movement of dew droplets from spine tips to their base, even against gravity. Spines emanating from one of the areoles of C. cinerea were submerged in water laced with fluorescent nanoparticles and this particular areole with its spines and a small area of stem was removed and imaged. These images clearly showed that fluorescent water had moved into the stem of the plant. Lines of vascular bundles radiating inwards from the surface areoles (from where the spines emanate) to the core of the stem were detected using magnetic resonance imaging, with the exception of F. wislizenii that does not harvest dew on its spines. Spine microstructures were examined using SEM images and surface roughness measurements (Ra and Rz) taken of the spines of C. cinerea It was found that a roughness gradient created by tapered microgrooves existed that could potentially direct surface water from a spine tip to its base.This article is part of the themed issue 'Bioinspired hierarchically structured surfaces for green science'.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Agua
/
Estructuras de las Plantas
/
Cactaceae
Idioma:
En
Revista:
Philos Trans A Math Phys Eng Sci
Asunto de la revista:
BIOFISICA
/
ENGENHARIA BIOMEDICA
Año:
2016
Tipo del documento:
Article
Pais de publicación:
Reino Unido