By
Keshar Man Bajracharya
Royal Nepal Academy of Sciences and Technology, Kathmandu, Nepal
Fire environment, fire regimes and ecological role of fire
Nepal is a small country of 14.7 million hectares and 23 million people situated in the central Himalayas, covering the northern edge of the Indian Gangetic plain to the high Himalayan ridges bordering the Tibet region of China. The country has topographic variation from 150 meters above sea level at the southern border to the highest mountain in the world (Everest at 8 848 m) in the north. Due to the east-west orientation of the mountain ranges, the country has a tropical climate in the south and temperate and alpine climates in the north. Accordingly, there are many different forest types in Nepal.
The Terai-Bhaber Region
The southernmost physiographic region of Nepal, called the Terai-Bhaber region, has an average altitudinal range between 150 and 300 m above sea level. It has a tropical climate with the main forest type comprised of sal (Shorea robusta) with smaller proportions of moist evergreen forest, dry deciduous forest, and khair-sisoo (Acacia catechu/Dalbergia sissoo) forest. The total forest area in this region amounts to about 475 000 ha within a total regional area of 2.11 million ha. There are also some 111 000 ha of shrubland and grassland.
In this region, the accumulated glabrous sal leaf litter is burned every year and during the process naturally regenerated sal seedlings and other herbs and shrubs are burned. However, larger green trees are usually not damaged and neither are the root systems of the sal seedlings, although the aerial parts are burned. Sal forests appear to be able to regenerate only when there are no surface fires.
The Siwaliks Hills and the Inner Terai Region
The next northern physiographic region includes the Siwaliks Hills and the Dun valleys (also called the Inner Terai in Nepal) and has an altitudinal variation between 300 and 1 000 m. It is characterized by a subtropical climate. The major forest types in this region include Schima-Castanopsis forests on the northern slopes of the Dun valley; the subtropical pine (Pinus roxburghii) forests on the Siwaliks ridges, dry scrubby forests on the southern slopes of the Siwaliks and moist Lauracea forests in the northern moist localities along with patches of sal forest. This region has 1 438 000 ha of forests and 104 000 ha of shrubland, grassland, and other non-cultivated woodlands within a total regional area of 1 886 000 ha.
Here, too, the vegetation along the southern drier slopes is burned during the dry season starting in March. Occasionally, bamboo brakes and grassy areas are destroyed, but the larger trees are usually spared. Nevertheless, the smoke created by forest fires and from agricultural burning make the valleys and the countryside very hazy and drab throughout the dry season.
The Middle Mountain Region
From 1 000 m along the southern foothills of the Mahabharat Range (ridge tops up to 3 000 m) to the hills of Nepal to an altitude of 2 500 m is called the Middle Mountain Region. It has mostly lower temperate forests. These are mainly broadleaved forests with Pinus roxburghii up to 2 000 m and Pinus wallichiana at the higher elevations. The river valleys in this region may be as low as 400 m. and sal forests (also called hill sal, a somewhat less luxuriant variety of Shorea robusta) and other subtropical broadleaf forests can occur here. The region has a total area of 4 442 000 ha with 1 811 000 ha of forests and 1 349 000 ha of shrubland, grassland and non-cultivated woodland.
Usually the pine forests and pine plantations, which are more susceptible to fire due to resin content, are frequently burned. As a result, the extensive chir pine (Pinus roxburghii) forests, which grow in the main habitat zone between 1 000 to 2 000 m, have become greatly fragmented.
The High Mountain Region
This region extends from 2 000 to 3 500 m above sea level, mostly with upper temperate forests of Quercus semicarpifolia, other broad-leaf forests composed mainly of Rhododendron spp., as well as coniferous forests of Pinus wallichiana, Abies pindrow and Picea smithiana. There is also a narrow belt of Tsuga brunoniana. This region has 1 630 000 hectares of forests together with 832 000 ha of shrubland, grassland and non-cultivated woodland within a total regional area of 2 960 000 ha.
In this region, coniferous forests are susceptible to extensive fire damage during the dry season, especially on windy days.
High Himal Region
This region mainly has alpine forests of birch (Betula utilis) as well as bushy rhododendrons and junipers. The total area of the region is 3 350 000 ha with only 155 000 ha of forests but with some 953 000 ha of shrubland and grassland. There is little cultivation here and a lot of snow- and rock-covered barren lands.
In all cases, the fire problems are acute for three to four months during the dry period between March and June every year. In most cases fires are caused by negligence. Sometimes grazers burn dry grassy areas purposely in order to get young shoots immediately after the first few pre-monsoon showers.
Narrative summary of major wildfire impacts on people, property, and natural resources during the 1990s
Every year wildfires destroy considerable forest resources in Nepal. Such destruction includes both timber and non-timber forest products. Although quantitative information is not available, forest fires are definitely degrading biological diversity in Nepal’s forests. In addition, fires cause soil erosion and induce floods and landslides due to the destruction of the natural vegetation. Occasionally, embers from forest fires also cause fires in nearby villages, especially in the Terai region where the roofs are made of thatched grass. Many villages are burned every year with loss of lives, cattle and other property.
At least one hundred villages are burned annually in Nepal, some of which are definitely destroyed by forest fires.
Fire management organization used in Nepal
There is no Organization for fighting forest fires in Nepal. The Department of Forests does not possess any special unit or team to deal with the problem of forest fire, including firefighting or management. None of the 75 district forest offices, with a number of graduate foresters and forestry technicians, has either the capacity or capability for preventing or fighting forest fires. It is probable that these offices under-report forest fire incidences and subsequent damage. Unless forest fire surveillance and monitoring are carried out by satellite imagery it will be difficult to make a good assessment of forest fire numbers, area burned and damage.
In Nepal some 10 000 local forest user groups have been formed with a total of 600 000 ha handed over to them as local community forests. Most of these community forests are located in the Middle Mountain Region where forests are severely fragmented and surrounded by villages. Here the community forest users are able to protect their respective forests from cutting and grazing. However, occasional forest fires occur due to the negligence of smoking travellers. The forest users are able to fight forest fires although they do not have proper tools and technical support. In fact, community forests are not managed properly, nor are forest fires fought in an appropriate manner.
Wildfire database
A wildfire database or other wildland fire statistics are not available. However, the magnitude of the forest area annually affected by fire is known. Sharma (1996) observed that in 1995 about 90 percent of the Terai forests were burned. Earlier observations by Goldammer (1993) confirmed this statement. Accordingly, the forest area burned annually must be in the order of more that 400 000 ha.
Use of prescribed fire to achieve resource management objectives
Prescribed fire is not used in Nepal to prevent forest fires. However, pine needles are collected for cattle bedding. Similarly, forest litter in the hills is collected and mixed with cattle dung for composting.
Public policies affecting wildfire impacts
Although the government devotes considerable attention in parliamentary discussions and the politicians and bureaucrats highlight the importance of forest fire prevention and firefighting, fire events are soon forgotten after the monsoon starts in June. During the fire season, Nepal Radio and Nepal Television broadcast old clips on forest fire prevention and firefighting.
Sustainable land use practices used in Nepal to reduce wildfire hazards and wildfire risks
In the past, district forest offices hired temporary fire guards, even though they were not effective in forest fire prevention. Of course, these temporary staff, as well as the permanent forestry staff, cannot achieve much in terms of forest fire prevention and firefighting without appropriate tools and organization.
Community involvement in fire management activities
Community involvement in fighting forest fires exists only in the community forests that have been established. Community involvement does not exist in the state forests and national parks, which constitute 90 percent of the Nepalese forests and related wild lands.
Conclusions
Forest fires occur annually in all the major physiographic/climatic regions of Nepal, including the Terai and Bhabar , the Siwaliks or the inner Terai, the Middle Mountains, and the High Mountains regions.
The main causes of forest fires are anthropogenic due to negligence and occasionally by deliberate burning to induce succulent grass growth for domestic animals.
Forest fires occur during the dry season from February to June and the nature (surface fire, crown fire, etc) as well as the severity varies greatly depending upon fire weather, fuel conditions, and physiography. Once the monsoon is established, usually by the middle of June, the fire problem disappears.
Forest fires destroy timber and non-timber forest products, although no data are available about the number of fires, severity and the amount of loss. Fires also reduce the biological diversity of the forests to a great extent. In addition, fires degrade the soil, inducing flood and landslide damage. Forest fires make the entire countryside hazy, thereby reducing aesthetic values for eco-tourism during the dry season.
Forest fire management is not practiced in Nepal. The community forest user groups control forest fires in their own forests, although they do not have a plan for systematic prevention and control of fires.
Systematic arrangements for prevention, control, and management of forest fires can be instituted in Nepal only when scientific forest management is implemented within the Department of Forests for state and community forests.
References
Goldammer, J.G. 1993. Feuer in Waldökosystemen der Tropen und Subtropen. Birkhäuser- Verlag, Basel-Boston, 251 pp.
Sharma, S.P. 1996. Forest fire in Nepal. Int. Forest Fire News 15: 36-39.
Source
Bajracharya, K.M. 2001. The forest fire situation in Nepal. Int. Forest Fire News 26.
