Centre for Plant Biodiversity Research
Quantifying bushfires for ecology using two electronic devices and biological indicators
(1) Centre for Plant Biodiversity Research, G.P.O. Box 1600, Canberra, A.C.T. 2601 Australia.
(2) CSIRO Division of Plant Industry, G.P.O. Box 1600, Canberra, A.C.T. 2601 Australia.
AbstractThe main fire input to models concerned with the ecological impact of fires on biota or soils is temperature, either as a critical instantaneous value or as a time sequence. An instrumented system for measuring temperature-time curves in fires is described. Based on shielded mineral-insulated thermocouples and a data logger, it has proven to be effective, rugged, reliable and portable in a wide range of vegetation types. This system is relatively expensive. To obtain more extensive coverage of fires, less expensively, and to also measure rates of spread of fires, a 'temperature-residence-time meter' (TRTM) has been developed. The meter records the times that temperatures persist over a chosen value. By analysing 106 temperature-time curves from near ground level during fires in woodlands and forests at Kakadu National Park, we have found that the durations of chosen high temperatures were statistically intercorrelated (r>0.82) but that the times to reach peak temperatures from 60C (a measure of flame residence time) were poorly correlated with these durations (r>0.40). Both electronic devices have widespread application for studies of fire ecology. Selected botanical attributes may be used as post-hoc indicators of fire properties.
Published in: Calm Science Supplement Vol. 4: 83-88 (1995) .
Updated 15 November, 1999 by Andrew Lyne