Flammability and Combustibility of Cistus Plant Groups in Tlemcen Region (Algeria)

Since antiquity, fire has played a dual role in Mediterranean forests. On the one hand, it renews and enriches a natural ecosystem by ensuring its biological uplift from the point of view of plant diversity if its frequency is low and, on the other hand, it destroys the vitality of a vegetation cover if its frequency is high. The forest of the Tlemcen region is an integral part of this regime. Forest fires are characterized by several types (ground fires, surface fires, crown fires, etc.) depending on the nature and architecture of the forest. For this purpose flammability and combustibility as a function of the water content of plant species are a key factor, in determining susceptibility to forest fires during the spring season, which is the objective of our study for the prediction and prevention in the short and long terms. The methodology adopted is that of Valette and Moro modified by Hachmi and Essaghi and by Henaoui. Thirty-eight plant species underwent flammability and combustibility tests using an infrared burner to rank our forests on a scale of different indices (flammability, combustibility, intensity of combustion and water ratio) that will determine their states. The results show that 87% of the vegetation cover is highly flammable, 42% very combustible, 63% are represented by a high intensity of combustion and 42% are represented by a high water content. 50% of these plant species are characterized by high flammability, combustibility and burning intensity despite their high water content.