Useful Life of Prescribed Fires in a Southern Mediterranean Basin: An Application to Pinus pinaster Stands in the Sierra Morena Range

Prescribed fire is a globally relevant fuel treatment for surface fuel management and wildfire hazard reduction. However, Mediterranean ecosystems are adapted to low and moderate fires; hence, the useful life of prescribed fires is limited. Useful life is defined as the effective rotation length of prescribed fires to mitigate fire spread based on critical surface intensity for crown combustion. In this sense, the useful life of a prescribed fire focuses on surface fuel dynamics and its potential fire behavior. In Pinus pinaster stands, the useful life can be established between 0 and 4 years. Canopy base height, time elapsed from the burning, postfire precipitation, and fine fuel moisture content during the burning were identified as the most important variables in postburn fuel dynamics. Other stand characteristics and postfire precipitation can improve the fine fuel and live fuel dynamics models. Our findings support prescribed fires as an effective fuel treatment in the medium term for forest fire prevention, according to stand characteristics and burning implementation conditions. In this sense, forest managers can use the proposed decision tree to identify the useful life of each prescribed fire based on fine fuel moisture content during burning implementation.

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Flame characteristics, temperature - time curves, and rate of spread in fires propagating in a bed of Pinus pinaster needles

International Journal of Wildland Fire ◽

10.1071/wf02063 ◽

2003 ◽

Vol 12 (1) ◽

pp. 67 ◽

Cited By ~ 64

Author(s):

José M. C. Mendes-Lopes ◽

João M. P. Ventura ◽

José M. P. Amaral

Keyword(s):

Wind Speed ◽

Moisture Content ◽

Pinus Pinaster ◽

Flame Height ◽

Fuel Moisture ◽

Propagation Models ◽

Fire Propagation ◽

Rate Of Spread ◽

Fuel Moisture Content ◽

Flame Angle

An extensive set of experiments was carried out in order to collect data to validate fire propagation models being developed in the context of an European research project. The experiments were performed in a dedicated burning tray (2.0 m × 0.70 m working section), where wind velocity, fuel moisture content and slope were varied to study fire propagation in beds of Pinus pinaster needles. All the runs were videotaped and, from the recordings, information on flame geometry (i.e. flame height, flame length and flame angle) and rate of spread was obtained. Temperature measurements were also carried out by a small tower of six thermocouples at different heights above the fuel bed. Results show that headfire rate of spread increases steeply with wind speed for wind-driven fires but does not depend on wind speed for backing fire spread rates. Rate of spread increases slightly with slope for up-hill propagation, and is not slope dependent for down-hill cases. Rate of spread decreases when fuel moisture content increases. Flame angle and flame height are also dependent on wind velocity, slope, and fuel moisture content. The importance of temperature for fire propagation is discussed, emphasizing the role of radiation heat transfer in the process. Correlations between temperature and other indicators of fire behaviour (namely the rate of spread) are presented. Results are discussed and compared. The results obtained provide a good database for the assessment of fire propagation models.

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Effects of curing on grassfires: I. Fuel dynamics in a senescing grassland

International Journal of Wildland Fire ◽

10.1071/wf14145 ◽

2015 ◽

Vol 24 (6) ◽

pp. 828 ◽

Cited By ~ 11

Author(s):

Susan Kidnie ◽

Miguel G. Cruz ◽

Jim Gould ◽

David Nichols ◽

Wendy Anderson ◽

...

Keyword(s):

Moisture Content ◽

Fuel Moisture ◽

Fire Dynamics ◽

Sampling Protocol ◽

Fuel Component ◽

Dead State ◽

Fuel Dynamics ◽

Green Fuels ◽

Soil Dryness ◽

Fuel Moisture Content

Grass senescence, or grassland curing, is a dynamic process in which grass fuels transition from a live to dead state and, in turn, influence fire dynamics. In the present study we examined the process of curing with specific consideration of changes in fuel structure that will affect potential fire behaviour. Our sampling protocol expanded the fuel component groups from two (live and dead) to four (green, senescing, new dead and old dead fuel). We found that all these components had significant fuel moisture content differences, thereby justifying our sampling protocol. Visual curing assessment predominantly resulted in an over-prediction bias of curing level and failed to capture the effect of the senescing process on fuel availability to combust due to misclassification of fuel components (e.g. senescing fuels with high fuel moisture content were classified as dead fuels because of their colouration). Models were developed to estimate the: (1) proportion of senescing and green fuels from knowledge of the current year’s dead fuel proportion; and (2) actual curing level from fuel moisture content and soil dryness level.

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Integrated mathematical modelling of a 105t/h biomass fired industrial watertube boiler system with varying fuel moisture content

Energy ◽

10.1016/j.energy.2021.120537 ◽

2021 ◽

pp. 120537

Author(s):

Ryno Laubscher ◽

Etienne De Villiers

Keyword(s):

Moisture Content ◽

Mathematical Modelling ◽

Fuel Moisture ◽

Fuel Moisture Content

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

10.1109/igarss47720.2021.9554874 ◽

2021 ◽

Author(s):

Chunquan Fan ◽

Binbin He ◽

Peng Kong ◽

Hao Xu ◽

Qiang Zhang ◽

...

Keyword(s):

Machine Learning ◽

Moisture Content ◽

Fuel Moisture ◽

Fuel Moisture Content

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

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2014.4049 ◽

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 researchersâ and forest managersâ 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.

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Establishment of empirical relations between fuel moisture content and the normalised difference vegetation index

Journal of soil science and plant nutrition ◽

10.4067/s0718-95162014005000053 ◽

2014 ◽

pp. 0-0

Author(s):

M Castro ◽

J.C Parra ◽

L. J Morales ◽

C Salas

Keyword(s):

Moisture Content ◽

Vegetation Index ◽

Fuel Moisture ◽

Empirical Relations ◽

Normalised Difference Vegetation Index ◽

Fuel Moisture Content

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

International Journal of Wildland Fire ◽

10.1071/wf12040 ◽

2013 ◽

Vol 22 (5) ◽

pp. 625 ◽

Cited By ~ 11

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.

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