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Journal of the International Association of Wildland Fire
RESEARCH ARTICLE

Monitoring live fuel moisture in semiarid environments using L-band radar data

M. A. Tanase A B D , R. Panciera A , K. Lowell C and C. Aponte B
+ Author Affiliations
- Author Affiliations

A Department of Infrastructure Engineering, University of Melbourne, Parkville, Vic. 3010, Australia.

B School of Ecosystem and Forest Sciences, University of Melbourne, 500 Yarra Boulevard, Richmond, Vic. 3121, Australia.

C Cooperative Research Centre for Spatial Information, 204 Lygon St, Carlton, Vic. 3053, Australia.

D Corresponding author. Email: mihai@tma.ro

International Journal of Wildland Fire 24(4) 560-572 https://doi.org/10.1071/WF14149
Submitted: 20 February 2014  Accepted: 11 December 2014   Published: 23 March 2015

Abstract

Timely information on spatial variation of live fuel moisture is critical for fire risk assessment and behaviour modelling. Using an airborne synthetic aperture radar system, the sensitivity of radar data to live fuel (i.e. canopy foliage) moisture was evaluated. Field and airborne measurements were collected over a 3-week period in a semiarid Australian forest dominated by white cypress pine (Callitris glaucophylla). Linear regression models were used to relate equivalent water thickness and live fuel moisture content to backscatter intensity and polarimetric decomposition components. Results showed that radar systems can provide estimates of live fuel moisture with similar or better accuracies for both equivalent water thickness (R2 = 0.7–0.8, root mean squared error (RMSE) = 15%) and live fuel moisture content (R2 = 0.6–0.7, RMSE = 10%) than those achieved in previous studies using optical-based vegetation indices. It was also possible to estimate soil moisture under the forest canopy with accuracies of 0.05 volume/volume (v v–1) (R2 = 0.5–0.6). This is particularly relevant in the context of fire management because moisture availability of fine fuels is related to soil water content.

Additional keywords: backscatter, Equivalent Water Thickness (EWT), live Fuel Moisture Content (FMC), Polarimetric L-band Imaging Synthetic aperture radar (PLIS), scattering.


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