摘要

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 (R-2=0.7-0.8, root mean squared error (RMSE)=15%) and live fuel moisture content (R-2=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)) (R-2=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.

  • 出版日期2015