Ignition probability of fine dead surface fuels of native Patagonian forests or Argentina

Zhang

et al. 2018

Forests

Abstract:Cigarette butts are an important human firebrand and account for a significant amount of man-made fires. To better address forest fires caused by cigarette butts, the influencing factors governing the ignition probability of cigarette butts can be used to establish a prediction model. This study obtains the influencing factors of the ignition probability of cigarette butts in order to establish a prediction model by constructing fuel beds composed of Mongolian oak leaves with varied fuel moisture content and packing ratios. A total of 2520 ignition experiments were then conducted by dropping cigarette butts on the fuel beds to test the burning probability of the fuels under varied wind speeds. Moisture content, wind speed, and their interaction significantly influenced ignition probability. In the absence of wind, the ignition probability is zero. The maximum moisture content of Mongolian oak leaves that could be ignited by cigarette butts was 15%. A logistic model and self-built model for predicting the ignition probability were established using these results; the mean absolute error values for the two models were 2.71% and 1.13%, respectively, and the prediction error of the self-built model was lower than that of the logistic model. This is important research to mitigate the threat of forest fires due to cigarette butts given the frequent occurrence of these events.

Section: Packing Ratiomentioning

confidence: 99%

Influence of Fuel Moisture Content, Packing Ratio and Wind Velocity on the Ignition Probability of Fuel Beds Composed of Mongolian Oak Leaves via Cigarette Butts

Zhang

et al. 2018

Forests

“…Let IC new = IC + b/a, Then P fnew = a × IC new (14) Forests Therefore, the daily fire probability can be expressed at least as a conduct of a constant and a new IC equal to the original IC with a shift (nearly 40% of zero shift). This indicates that the established method with modification can be used in the area to separate the effects of firebrand and the fuel-weather complex on fire occurrence probability.…”

Section: Suitability Of the Methodsmentioning

confidence: 99%

“…Firebrand probability is affected by human activities and biophysical factors such as distance to roads [8][9][10][11]. Fuel ignition probability is mainly affected by fuel moisture content and firebrand type [12][13][14]. Probability of an ignition spreading to a reported fire is affected mainly by rate of spread [15].…”

Section: Introductionmentioning

confidence: 99%

“…Research on these probability models in China is too limited to establish such a probabilistic method for the region. However, intensive studies have been conducted on ignition probability by different firebrands [13,14,[16][17][18][19][20] though only a few works on the probability of an ignition spreading to a reportable fire have been conducted. Establishing such a probabilistic method for China by aid of current existing models would be a practical way to achieve the above goal.…”

Section: Introductionmentioning

confidence: 99%

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A Probabilistic Method Predicting Forest Fire Occurrence Combining Firebrands and the Weather-Fuel Complex in the Northern Part of the Daxinganling Region, China

Zhang

2018

Forests

The fire danger rating method currently used in the northern part of the Daxinganling Region with the most severe forest fires in China only uses weather variables without considering firebrands. The discrepancy between fire occurrence and fire risk by FFDWR (Forest Fire-Danger Weather Rating, a method issued by the National Meteorological Bureau, that is used to predict forest fire probability through links between forest fire occurrence and weather variables) in the northern part is more obvious than that in the southern part. Great discrepancy has emerged between fire danger predicted by the method and actual fire occurrence in recent years since a strict firebrand prohibition policy has significantly reduced firebrands in the region. A probabilistic method predicting fire probability by introducing an Ignition Component (IC) in the National Fire Danger Rating System (NFDRS) adopted in the United States to depict effects of both firebrand and weather-fuel complex on fire occurrence is developed to solve the problem. The suitability and accuracy of the new method in the region were assessed. Results show that the method is suitable in the region. IC or the modified IC can be adopted to depict the effect of the weather-fuel complex on fire occurrence and to rate fire danger for periods with fewer firebrands. Fire risk classes and corresponding preparedness level can be determined from IC in the region. Methods of the same principle could be established to diminish similar discrepancy between actual fire occurrence and fire danger in other countries.

“…Describing forest fuels and quantifying them is important for understanding the behavior of fire, as it provides information for fire management activities, including prescribed burning, difficulty in suppression, hazard assessment and fuel treatment BATISTA, 2007). The characteristics of forest herbaceous and shrub vegetation fuels and their importance in the ignition and spread of fires have been the object of study by several authors (SAGLAM et al, 2008;FIDELIS et al, 2010;REINER et al, 2010;RIBEIRO et al, 2011;CASTEDO-DOURADO et al, 2012;KUNST et al, 2012;FERNÁNDEZ et al, 2013;BIANCHI;DEFOSSE, 2014;WHITE et al, 2014;PERREIRA et al, 2016;WHITE et al, 2017;SEGER et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

Shrub Fuel Characteristics in the Private Natural Heritage Reserve Caminho Das Tropas, Paraná – Brazil

Seger¹,

Batista

Tetto

et al. 2020

This research was carried out in the Private Natural Heritage Reserve (PNHR) “Caminho das Tropas”, located in Palmeira, Paraná state - Brazil, in an area dominated by natural fields. The objective was to characterize the shrub fuel of the grassy-woody steppe in the area. For the sampling, an area of 25 hectares was fenced and 100 plots sized 50 x 50 m (0.25 ha) were allocated. The plots were grouped into two treatments: one containing over 50% density and the other less than 50% density and regular distribution of shrub vegetation. The average load of fuel obtained for the first category was 1.2886 Mg.ha-1, being 0.9667 Mg.ha-1of living material and 0.3219 Mg.ha-1 of dead material. For the second category, the load was 0.9328 Mg.ha-1 , with 0.6516 and 0.2812 Mg.ha-1of live and dead fuel respectively. The average moisture content of the fuel in the first treatment was 87.90% and in the second, 81.49%. The characteristics found in the shrub fuel of the study area are compatible with the results found in the literature for Brazilian natural grasslands vegetation.