scholarly journals The Relevance of Current Hazard Stick Reading to the Moisture Content of Logging Slash

1969 ◽  
Vol 45 (2) ◽  
pp. 107-113
Author(s):  
Gy. Péch
Keyword(s):  
Moisture Content ◽  
Fuel Moisture ◽  
Daily Fluctuation ◽  
Individual Measurement ◽  
Moisture Contents ◽  
Red Cedar ◽  
Drying Rates ◽  
Fuel Moisture Content ◽  
Maximum Moisture Content ◽  
Composite Samples

Seven composite samples of western red cedar and western hemlock logging slash of 0.25 to 2 inches diameter were exposed on top of and within the bottom third of a fuel bed in the interior wet belt of British Columbia in August 1965. Their moisture contents were measured regularly 24 hours a day and compared with the moisture content of an exposed B.C. hazard stick on the basis of both the hourly drying rates on 1 clear day and the daily loss of moisture, relative to the morning maximum moisture content, for a period of 6 drying days after rain. The absolute moisture content values, the hourly rates of drying, and the daily fluctuation of the moisture content of the hazard stick differed from those of the fuel samples at all times. It was concluded that cedar-hemlock slash fuel moisture content cannot be predicted numerically from an individual measurement of the moisture content of freely exposed hazard sticks in those years when the slash retains a tight bark. Counting the number of drying days after rain proved to be of little practical value.

The initiation of fire spread in shrubland fuels recreated in the laboratory

2010 ◽  
Vol 19 (4) ◽  
pp. 512 ◽  
Author(s):  
Matt P. Plucinski ◽  
Wendy R. Anderson ◽  
Ross A. Bradstock ◽  
A. Malcolm Gill
Keyword(s):  
Moisture Content ◽  
Classification Tree ◽  
Fire Spread ◽  
Fuel Moisture ◽  
Shrub Layer ◽  
Moisture Contents ◽  
Layer Density ◽  
Live Fuel Moisture ◽  
Fuel Moisture Content ◽  
The Impact

Fire-prone shrub-dominated vegetation communities cover a considerable portion of Australia, including areas fringing urban development. Near urban interfaces, they are actively managed with prescribed fire to reduce the risk of wildfire (unplanned fire). Knowledge of the range of conditions that allow fires to spread or fail to do so is limited and can inconvenience fire managers when conducting prescribed burns. A series of experimental ignitions conducted in miniature shrublands reconstructed in the laboratory were used to investigate factors that influence ignition thresholds. The miniature shrublands were composed of foliage from the shrub Allocasuarina nana and were prepared over a range of moisture contents and densities. The impact of dead fuel within the aerial structure of the shrubs was also investigated, as was the presence and absence of wind and litter. The most important factors for spread initiation were identified using logistic regression analysis and classification tree modelling. The presence of litter, live fuel moisture content, shrub-layer density, presence of wind, and the amount and continuity of the dead elevated fuel were all found to influence spread sustainability. There was a negative interaction between shrub-layer density and live fuel moisture content, showing the effect of density to be less at higher moisture contents.

scholarly journals MEASUREMENT OF WOOD MOISTURE CONTENT USING THE COLMAN ELECTRODE

1965 ◽  
Vol 41 (3) ◽  
pp. 352-363
Author(s):  
W. J. Bloomberg ◽  
D. Farrell
Keyword(s):  
Moisture Content ◽  
Soil Moisture Content ◽  
Black Cottonwood ◽  
Wood Moisture ◽  
Moisture Contents ◽  
Red Cedar ◽  
The Mean ◽  
Cottonwood Trees ◽  
Almost All ◽  
Maximum Moisture Content

Colman electrodes were inserted into stem sections of Douglas-fir, western hemlock, western red cedar and black cottonwood and resistance readings were taken at wood moisture contents of 10% to 100% of maximum moisture content. In almost all the conifer sections tested, 85% or more of the readings lay within limits of ±10% moisture content about the mean curve, and over 50% were within ±5%. The variation was greater for black cottonwood. Variation was also greater in the larger than in the smaller sections. The curves for individual sections within each species had certain characteristics in common, but no two curves were identical.Resistance readings given by Colman electrodes inserted into living black cottonwood trees showed a fairly good correlation with soil moisture content when the trees were subjected to cycles of drought and watering.

The likelihood of ignition of dry-eucalypt forest litter by firebrands

2015 ◽  
Vol 24 (2) ◽  
pp. 225 ◽  
Author(s):  
P. F. M. Ellis
Keyword(s):  
Wind Speed ◽  
Moisture Content ◽  
Eucalyptus Globulus ◽  
Forest Litter ◽  
Fuel Moisture ◽  
Ignition Probability ◽  
Moisture Contents ◽  
Eucalypt Forest ◽  
Fuel Moisture Content ◽  
Practical Measure

Ignition probability of litter of dry-eucalypt forest by standard flaming and glowing firebrand samples was tested in a wind tunnel. Standard flaming firebrands were sections of bamboo sate stick 50 mm long, and flamed for ~9 s in still air. Standard glowing samples were sections of shed bark of Eucalyptus globulus 50 mm long, 15 mm wide and ~2 mm in thickness. These were burnt at their terminal velocities and at deposition had a mean mass of 0.2 g and would remain glowing for 2.5 min in wind. Ignition was tested using air speeds of zero, 1 and 2 m s–1, and oven-dried fuel moisture contents between 4 and 21%. For flaming samples, ignition probability was insensitive to variation in fuel and airflow characteristics and was a function of wind (no wind or wind) and fuel moisture content. For glowing samples, ignition probability was a function of fuel moisture content and wind speed. The models confirm the dominating influence of fuel moisture, are consistent with expert observations in the field and provide a practical measure of ignition likelihood by firebrands. It is argued that airflow turbulence and relative humidity are potentially significant for ignition by glowing firebrands.

Predicting 1-H Dead Fuel Moisture Content at Regional Scales Using Machine Learning from Himawari-8 Data

2021 ◽  
Author(s):  
Chunquan Fan ◽  
Binbin He ◽  
Peng Kong ◽  
Hao Xu ◽  
Qiang Zhang ◽  
...  
Keyword(s):  
Machine Learning ◽  
Moisture Content ◽  
Fuel Moisture ◽  
Fuel Moisture Content

scholarly journals Evaluating the Effects of Projected Climate Change on Forest Fuel Moisture Content

2014 ◽  
Vol 37 ◽  
pp. 65-69
Author(s):  
Kellen Nelson ◽  
Daniel Tinker
Keyword(s):  
Climate Change ◽  
Moisture Content ◽  
Stand Structure ◽  
Canopy Cover ◽  
Fire Season ◽  
Climate Change Scenarios ◽  
Fuel Moisture ◽  
Mature Forest ◽  
Forest Fuel ◽  
Fuel Moisture Content

Understanding how live and dead forest fuel moisture content (FMC) varies with seasonal weather and stand structure will improve researchers’ and forest managers’ ability to predict the cumulative effects of weather on fuel drying during the fire season and help identify acute conditions that foster wildfire ignition and high rates of fire spread. No studies have investigated the efficacy of predicting FMC using mechanistic water budget models at daily time scales through the fire season nor have they investigated how FMC may vary across space. This study addresses these gaps by (1) validating a novel mechanistic live FMC model and (2) applying this model with an existing dead FMC model at three forest sites using five climate change scenarios to characterize how FMC changes through time and across space. Sites include post-fire 24-year old forest, mature forest with high canopy cover, and mature forest affected by the mountain pine beetle with moderate canopy cover. Climate scenarios include central tendency, warm/dry, warm/wet, hot/dry, and hot/wet.

Effects of distribution of bulk density and moisture content on shrub fires

2013 ◽  
Vol 22 (5) ◽  
pp. 625 ◽  
Author(s):  
Ambarish Dahale ◽  
Selina Ferguson ◽  
Babak Shotorban ◽  
Shankar Mahalingam
Keyword(s):  
Moisture Content ◽  
Spatial Variation ◽  
Bulk Density ◽  
Solid Fuel ◽  
Numerical Solutions ◽  
Propagation Speed ◽  
Fire Spread ◽  
Fuel Moisture ◽  
Combustion Heat ◽  
Fuel Moisture Content

Formulation of a physics-based model, capable of predicting fire spread through a single elevated crown-like shrub, is described in detail. Predictions from the model, obtained by numerical solutions to governing equations of fluid dynamics, combustion, heat transfer and thermal degradation of solid fuel, are found to be in fairly good agreement with experimental results. In this study we utilise the physics-based model to explore the importance of two parameters – the spatial variation of solid fuel bulk density and the solid fuel moisture content – on the burning of an isolated shrub in quiescent atmosphere. The results suggest that vertical fire spread rate within an isolated shrub and the time to initiate ignition within the crown are two global parameters significantly affected when the spatial variation of the bulk density or the variation of fuel moisture content is taken into account. The amount of fuel burnt is another parameter affected by varying fuel moisture content, especially in the cases of fire propagating through solid fuel with moisture content exceeding 40%. The specific mechanisms responsible for the reduction in propagation speed in the presence of higher bulk densities and moisture content are identified.

Modelling fine fuel moisture content and the likelihood of fire spread in blue gum (Eucalyptus globulus) litter

2014 ◽  
pp. 353-359
Author(s):  
Anita Pinto ◽  
Juncal Espinosa-Prieto ◽  
Carlos Rossa ◽  
Stuart Matthews ◽  
Carlos Loureiro ◽  
...  
Keyword(s):  
Moisture Content ◽  
Eucalyptus Globulus ◽  
Fire Spread ◽  
Fuel Moisture ◽  
Fuel Moisture Content ◽  
Blue Gum
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