Wildfires are one of the most dangerous natural disasters on the planet. During them, a huge number of living beings die. Often, entire villages or villages perish in the flames. Natural fires are subject to strict classification. Each type of combustion and propagation has its own terms and concepts. This serves to facilitate the definition of firefighting tasks. To combat the elements, not only ground forces are involved, but also special fire helicopters and aircraft. Volunteers are often called in to extinguish the fire, as well as military personnel of district units.
Natural fires are forest and agricultural, and those, in turn, have a number of subsections. Grass fires are the main cause of forest fires. Dry grass flares up quickly, but the rate of spread of such a fire depends on the wind. To extinguish, a backfire is used, which, under control, destroys dead wood and leaves an uncontrolled fire without fuel.
Forest fires are divided into crown, ground and litter fires. Their distribution depends on wind speed and direction, terrain and weather conditions. During a crown fire, only the crowns of trees most often burn, but when the wind weakens, the fire can move lower, and in this case, burnwill be each tree entirely. Coniferous forests are mainly affected by crown fires.
Natural fires often occur due to the human factor. A carelessly left fire or an unextinguished cigarette can lead to a bedding fire. In this case, burning of the litter or peat layer of forest soil occurs. Underground fires are dangerous because they completely destroy the root system of trees. They spread very slowly, up to several meters per day. The burning area is often round or oval in shape. Burnt trees fall to the center of the fire. Extinguishing such a fire is complicated by the absence of a visible source of fire, as well as the ability of peat to pass water into the deeper layers of the soil, while remaining dry. People and equipment can fall into burnt areas.
Ground fire is the most common type of forest fire. During it, grass, bedding, litter and the lower part of tree trunks burn. It has a fairly high propagation speed - about 5 meters per minute. A ground fire in some areas can either go to the crowns of trees or penetrate underground. During combustion, a kind of "thermal column" is formed above the hearth. Hot air rushes upwards, picking up coals and burning leaves, which can then enter areas not yet exposed to fire.
Wildfires are one of the main scourges of Russian forests. Every year, thousands of cubic meters of wood die in them, entire ecologicalzones. Fires in Russia with its huge forest areas cause great damage to the country. Burning in the summer of 2010, peat bogs in the Moscow region dragged the entire capital into smoke and burning. Every year, about 25,000 large forest fires are registered in our country, which cover an area of up to 2 million hectares.
