Although two-thirds of the total geographical area of Himachal Pradesh is legally classified as forest area, much of this area is permanently under snow, glaciers, cold desert or alpine meadows and is above the tree line. This leaves an effective forest cover of around 28 percent of the total area which amounts to 15,434 square kilometres, as per the Forest Survey of India. Chir Pine, Deodar, Oak, Kail, Fir and Spruce are some of the common trees found here.Forest fires are a recurrent annual phenomenon in the state, and most commonly occur in Chir Pine forests.
In the summer season, forest fires occur frequently in the low and middle hills of the state, where forests of Chir Pine are common. The dry summer season from March to June coincides with the shedding of highly-combustible needles by Chir Pine trees. Once the fallen dry needles catch fire, it can spread quickly over the entire forest due to the action of the wind. However, due to their thick bark, the Chir Pine trees are themselves relatively unharmed by these fires, and can spring back to life during the monsoon season.
During the post-monsoon season and in winters, forest fires are also reported in higher areas, including parts of Shimla, Kullu, Chamba, Kangra and Mandi districts, where they usually occur in grasslands.
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.
The dry leaf litter on the forest ground acts as a ready fuel. Fallen tree leaves, dry grass, weeds, low brushwood, deadwood on the forest floor, logs and stumps etc form the surface fuels. Below the loose litter, decaying materials such as humus, wood, shrubs, roots, much and peat can also support the combustion. Above the surface level, dry standing trees, mosses, lichens, dry epiphytic or parasitic plants, and fallen branches trapped in the understorey can spread the fire to the upper foliage and the tree crowns.
Causes of forest fires can also be divided into two broad categories: environmental (which are beyond control) and human related (which are controllable).
Environmental causesare largely related to climatic conditions such as temperature, wind speed and direction, level of moisture in soil and atmosphere and duration of dry spells. Other natural causes are the friction of bamboos swaying due to high wind velocity and rolling stones that result in sparks setting off fires in highly inflammable leaf litter on the forest floor.
Human related causesresult from human activity as well as methods of forest management. These can be intentional or unintentional, for example:
- graziers and gatherers of various forest products starting small fires to obtain good grazing grass as well as to facilitate gathering of minor forest produce like flowers of Madhuca indica and leaves of Diospyros melanoxylon
- the centuries old practice of shifting cultivation (especially in the North-Eastern region of India and inparts of the States of Orissa and Andhra Pradesh).
- the use of fires by villagers to ward off wild animals
- fires lit intentionally by people living around forests for recreation
- fires started accidentally by careless visitors to forests who discard cigarette butts.
Consequences of forest Fires:
Fires are a major cause of forest degradation and have wide ranging adverse ecological, economic and social impacts, including:
- loss of valuable timber resources
- degradation of catchment areas
- loss of biodiversity and extinction of plants and animals
- loss of wildlife habitat and depletion of wildlife
- Forest fires may destroy organic matter in the soil and expose the top layer to erosion. They may also impact the wildlife by burning eggs, killing young animals and driving the adult animals away from their safe haven.
- loss of natural regeneration and reduction in forest cover
- global warming
- loss of carbon sink resource and increase in percentage of CO2 in atmosphere
- change in the microclimate of the area with unhealthy living conditions
- soil erosion affecting productivity of soils and production
- ozone layer depletion
- health problems leading to diseases
- loss of livelihood for tribal people and the rural poor, as approximately 300 million people are directly dependent upon collection of non-timber forest products from forest areas for their livelihood.
Prevention and Early Control:
Forecasting fire-prone days using meteorological data, clearing camping sites of dried biomass, early burning of dry litter on the forest floor, growing strips of fire-hardy plant species within the forest, and creating fire lines in the forests are some of the methods to prevent fires (fire lines are strips in the forest kept clear of vegetation to prevent the fire from spreading). Once a fire starts, early detection and quick action by fire-fighting squads is crucial
Source:The Indian Express
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