The most common hazard in forests is forests fire. Forests fires are as old as the forests themselves. They pose a threat not only to the forest wealth but also to the entire regime to fauna and flora seriously disturbing the bio-diversity and the ecology and environment of a region. During summer, when there is no rain for months, the forests become littered with dry senescent leaves and twinges, which could burst into flames ignited by the slightest spark. The Himalayan forests, particularly, Garhwal Himalayas have been burning regularly during the last few summers, with colossal loss of vegetation cover of that region.
Causes of Forest Fire
Forest fires are caused by Natural causes as well as Man made causes
- Natural causes – Many forest fires start from natural causes such as lightning which set trees on fire. However, rain extinguishes such fires without causing much damage. High atmospheric temperatures and dryness (low humidity) offer favorable circumstance for a fire to start.
- Man made causes – Fire is caused when a source of fire like naked flame, cigarette or bidi, electric spark or any source of ignition comes into contact with inflammable material.
Classification of Forest Fire
Forest fire can broadly be classified into three categories;
- Natural or controlled forest fire.
- Forest fires caused by heat generated in the litter and other biomes in summer through carelessness of people (human neglect) and
- Forest fires purposely caused by local inhabitants.
Types of Forest Fire
The types of forest fire are as follows,
- Surface Fire – A forest fire may burn primarily as a surface fire, spreading along the ground as the surface litter (senescent leaves and twigs and dry grasses etc).
- Underground/ Muck fires – The fires of low intensity, consuming the organic matter beneath and the surface litter of forest floor, they spread entirely underground and burn for some meters below the surface. This fire spreads very slowly and in most of the cases it becomes very hard to detect and control such type of fires. They may continue to burn for months and destroy vegetative cover of the soil.
- Ground Fire – These fires are seen in Arctic tundra or taiga, and organic soils of swamps or bogs. This fire burns root and other material on or beneath the surface i.e. burns the herbaceous growth on forest floor together with the layer of organic matter in various stages of decay. They are more damaging than surface fires, as they can destroy vegetation completely. They are more often ignited by surface fires.
- Crown Fire – In this, crown of trees and shrubs burn, often sustained by a surface fire. A crown fire is particularly very dangerous in a coniferous forest because resinous material and up to the flame.
- Firestorms – Among the forest fires, the fire spreading most rapidly is the firestorm, which is an intense fire over a large area. Temperatures inside these storms can reach around 2,000 degrees Fahrenheit.
- The youngest mountain ranges of Himalayas are the most vulnerable stretches of the world susceptible to forest fires.
- The forests of Western are more frequently vulnerable to forest fires as compared to those in Eastern Himalayas. This is because forests of Eastern Himalayas grow in high rain density.
- With large scale expansion of chirr (Pine) forests in many areas of the Himalayas the frequency and intensity of forest fires has increased.
Preparedness and Mitigation Measures
- Forest fires are usually seasonal. They usually start in the dry season and can be prevented by adequate precautions.
- During the British period, fire was prevented in the summer through removal of forest litter all along the forest boundary. This was called “Forest Fire Line” This line used to prevent fire breaking into the forest from one compartment to another. The collected litter was burnt in isolation. Generally, the fire spreads only if there is continuous supply of fuel (Dry vegetation) along its path. The best way to control a forest fire is therefore, to prevent it from spreading, which can be done by creating firebreaks in the shape of small clearings of ditches in the forests.
The followings are the important precautions against fire:
- To keep the source of fire or source of ignition separated from combustible and inflammable material.
- To keep the source of fire under watch and control.
- Not allow combustible or inflammable material to pile up unnecessarily and to stock the same as per procedure recommended for safe storage of such combustible or inflammable material.
- To adopt safe practices in areas near forests viz. factories, coalmines, oil stores, chemical plants and even in household kitchens.
- To incorporate fire reducing and fire fighting techniques and equipment
The Indian Air Force recently deployed two Mi-17V5 helicopters equipped with Bambi Bucket to control the forest fires. The forest fires have been raging in the hills of south Mizoram. The Lunglei and Aizwal of Mizoram where the forest fires are currently raging is the most fire-prone zone in
Most Fire Prone Zones
India according to the Forest Fire Disaster Management report, 2014. So far, Lunglei has recorded 13,453 forest fires between 2003 and 2016.
Forest Fires in Mizoram
The fire season of the state is between February and May. The maximum incidents of fires reported in the months of April and May
• Slash and burn or shifting cultivation, burning farm residues, collection of non-timber forest produces and clearance of land for other purposes. In 2021, so far, the VIIRS (Visible Infrared Imaging Radiometer Suite) has reported 1,604 fire alerts.
Forest Fire Disaster Management Report, 2014
- It was prepared by the National Institute of Disaster Management, New Delhi
Strengthening Forest Fire Management in India Report
- It was jointly prepared by Ministry of Environment, Forest and Climate Change and World Bank.
- A least 60% of Indian districts are affected by forest fires.
- The states in the North East account for the greatest share of fire detections.
- The Central India is the largest area affected by forest fires.
Forest Survey of India, 2019
The Survey divided the forest fire prone into following zones:
- Extremely fire-prone areas accounted to 3.89% of total forest cover
- Very highly fire-prone areas accounted to 6.01%
- Highly fire prone areas: 11.50%
- Together these three categories add up to 21.4% of forest cover.