Catalog Home Page

Why do biogenic volatile organic compounds (BVOCs) derived from vegetation fire not induce soil water repellency?

Uddin, S.M.M., Daniel, N.R.R., Harper, R.J. and Henry, D.J. (2017) Why do biogenic volatile organic compounds (BVOCs) derived from vegetation fire not induce soil water repellency? Biogeochemistry, 134 (1-2). pp. 147-161.

Link to Published Version: https://doi.org/10.1007/s10533-017-0352-7
*Subscription may be required

Abstract

Biogenic volatile organic compounds (BVOCs) are continually emitted from plants and are also a component of smoke during vegetation fire. Although vegetation fire events have been shown to have implications for the dynamics of soil water repellency (SWR) and there have been anecdotal reports that forest smoke can induce water repellency, the role of BVOCs in this process has not been explored. Accordingly, we investigated a selection of major BVOCs (cis-3-hexen-1-ol; levoglucosenone; 2-methyl-3-buten-2-ol; cineole; α-phellandrene; α-terpinene) that are emitted from the dominant native vegetation of Australia during fire. The potential of each compound to induce SWR was investigated by applying different loadings on acid washed sand (AWS) (300–350 µm diameter) and then assessing water repellency with the molarity of ethanol drop test. A long-chain amphiphilic molecule (palmitic acid) was also applied to AWS for comparison. Although palmitic acid was effective at inducing water repellency, the BVOCs were not, even at high loadings (5 × 10−4 mol g−1). Fully atomistic molecular dynamics simulations complemented the experimental measurements. These studies suggested that poor expression of water repellency by the BVOCs could be explained by their tendency to exhibit weak interactions towards the quartz surface but strong molecule–molecule attractions. In comparison, the long-chain amphiphilic molecules exhibited a balance between molecule–molecule and molecule–surface interactions that favored surface adhesion, which in turn led to the formation of a hydrophobic layer.

Publication Type: Journal Article
Murdoch Affiliation: School of Engineering and Information Technology
School of Veterinary and Life Sciences
Publisher: Springer Verlag
Copyright: © 2017 Springer International Publishing AG
URI: http://researchrepository.murdoch.edu.au/id/eprint/37575
Item Control Page Item Control Page