Advanced

Solar-powered ventilation of African termite mounds

Ocko, Samuel A.; King, Hunter; Andreen, David LU ; Bardunias, Paul; Turner, J. Scott; Soar, Rupert and Mahadevan, L. (2017) In Journal of Experimental Biology 220(18). p.3260-3269
Abstract

How termite mounds function to facilitate climate control is still only partially understood. Recent experimental evidence in the mounds of a single species, the south Asian termite Odontotermes obesus, suggests that the daily oscillations of radiant heating associated with diurnal insolation patterns drive convective flow within them. How general this mechanism is remains unknown. To probe this, we consider the mounds of the African termite Macrotermes michaelseni, which thrives in a very different environment. By directly measuring air velocities and temperatures within the mound, we see that the overall mechanisms and patterns involved are similar to that in the south Asian species. However, there are also some notable differences... (More)

How termite mounds function to facilitate climate control is still only partially understood. Recent experimental evidence in the mounds of a single species, the south Asian termite Odontotermes obesus, suggests that the daily oscillations of radiant heating associated with diurnal insolation patterns drive convective flow within them. How general this mechanism is remains unknown. To probe this, we consider the mounds of the African termite Macrotermes michaelseni, which thrives in a very different environment. By directly measuring air velocities and temperatures within the mound, we see that the overall mechanisms and patterns involved are similar to that in the south Asian species. However, there are also some notable differences between the physiology of these mounds associated with the temporal variations in radiant heating patterns and CO2 dynamics. Because of the difference between direct radiant heating driven by the position of the sun in African conditions, and the more shaded south Asian environments, we see changes in the convective flows in the two types of mounds. Furthermore, we also see that the south Asian mounds showa significant overturning of stratified gases, once a day, while the African mounds have a relatively uniform concentration of CO2. Overall, our observations show that despite these differences, termite architectures can harness periodic solar heating to drive ventilation inside them in very different environments, functioning as an external lung, with clear implications for human engineering.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Animal architecture, Termite mounds, Ventilation
in
Journal of Experimental Biology
volume
220
issue
18
pages
10 pages
publisher
The Company of Biologists Ltd
external identifiers
  • scopus:85029786575
  • wos:000411199600013
ISSN
0022-0949
DOI
10.1242/jeb.160895
language
English
LU publication?
yes
id
8f21f90b-6a4e-4248-9316-772314398564
date added to LUP
2017-11-28 13:27:45
date last changed
2018-05-06 04:38:26
@article{8f21f90b-6a4e-4248-9316-772314398564,
  abstract     = {<p>How termite mounds function to facilitate climate control is still only partially understood. Recent experimental evidence in the mounds of a single species, the south Asian termite Odontotermes obesus, suggests that the daily oscillations of radiant heating associated with diurnal insolation patterns drive convective flow within them. How general this mechanism is remains unknown. To probe this, we consider the mounds of the African termite Macrotermes michaelseni, which thrives in a very different environment. By directly measuring air velocities and temperatures within the mound, we see that the overall mechanisms and patterns involved are similar to that in the south Asian species. However, there are also some notable differences between the physiology of these mounds associated with the temporal variations in radiant heating patterns and CO<sub>2</sub> dynamics. Because of the difference between direct radiant heating driven by the position of the sun in African conditions, and the more shaded south Asian environments, we see changes in the convective flows in the two types of mounds. Furthermore, we also see that the south Asian mounds showa significant overturning of stratified gases, once a day, while the African mounds have a relatively uniform concentration of CO<sub>2</sub>. Overall, our observations show that despite these differences, termite architectures can harness periodic solar heating to drive ventilation inside them in very different environments, functioning as an external lung, with clear implications for human engineering.</p>},
  author       = {Ocko, Samuel A. and King, Hunter and Andreen, David and Bardunias, Paul and Turner, J. Scott and Soar, Rupert and Mahadevan, L.},
  issn         = {0022-0949},
  keyword      = {Animal architecture,Termite mounds,Ventilation},
  language     = {eng},
  month        = {09},
  number       = {18},
  pages        = {3260--3269},
  publisher    = {The Company of Biologists Ltd},
  series       = {Journal of Experimental Biology},
  title        = {Solar-powered ventilation of African termite mounds},
  url          = {http://dx.doi.org/10.1242/jeb.160895},
  volume       = {220},
  year         = {2017},
}