Optimum Allocation of Firebreaks Networks during the Design Process in Golestan National Park, Northeastern Iran ^†

Due to their increasing frequency wildfires and the area burned in natural areas, wildfires are becoming increasingly challenging to control. Firebreaks are an effective method to stop the spread of wildfires. To find the optimal allocation of firebreaks, a weight-linear combination (WLC) with an AHP fuzzy method was used to allocate optimum fuel breaks networks in the Golestan National Park in northeastern Iran. The effective factors that may impact the designing of firebreaks, including climate, topography, fuel, and fire behavior characteristics, were determined. The WindNinja simulator was used to create wind direction and speed layers based on the prevailing wind direction (250°) and three wind-speed scenarios (low = 6, medium = 12, and high = 18 mph). FlamMap (basic FB and MTT algorithms) was used to predict potential characteristics of fire behavior, including burn probability, rate of spread, flame length, and fireline intensity, under constant weather and fuel moisture conditions, using historic ignition points in the most recent ten years in the study area. Furthermore, the suitability map of the fuel-break allocation was determined by the AHP weights and the weighted linear combination (WLC) method and was considered effective (

Table 1. Final weights of effective criteria for allocating fire break network.

Criteria	Weight	Sub Criteria	Weight	Final Weight
Topography	0.161	Aspect	0.41	0.06601
		Slope	0.59	0.09499
		Elevation	0	0
Fire history	0.164	Burned area	0.309	0.05068
		Fire points	0.691	0.11332
Fire behavior	0.164	Flame length	0.038	0.00623
		Fire line intensity	0.186	0.0305
		Heat per unit area	0.265	0.04346
		Fire spread	0.23	0.03772
		Ignition potential map	0.282	0.04625
Wind characteristics	0.169	Wind speed	0.049	0.00828
		Wind effect index	0.426	0.07199
		Wind speed mid flame	0.525	0.08873
Fuel characteristics	0.172	Fuel load	0.333	0.05728
		Fuel type	0.336	0.05779
		Fuel moisture	0.331	0.05693
Distance of barriers	0.171			0.171

).

The firebreaks network was designed and allocated to the study area based on the suitability firebreak allocation map. To evaluate firebreaks performance across the landscape, four historical large fires (>100 ha) were simulated to investigate the effectiveness of the firebreaks with the Kappa coefficient corresponding index. An analysis of the AHP questionnaire showed that the fuel characteristics, the distance of barriers, and wind factors are the most effective criteria in firebreak allocation, with an inconsistency rate of 0.02. In addition, the evaluation of the suggested firebreaks showed the ability of fire breaks to stop the spread of fire (Kappa coefficient: 0.50, 0.43, 0.48, 0.61) (Figure 1).