Forest Fire Situation in Sri Lanka (IFFN No. 26)

The Forest Fire Situation in Sri Lanka

(IFFN No. 26 – January 2002, p. 96-100)


Introduction

Sri Lanka is a tropical island with a land area of 65,000 km2. Current population is estimated at 18 million and population growth is around 1.1 percent per annum. The economy is predominantly agriculture and the per capita income is around US$ 740.

The total area of natural closed-canopy forest in 1992 is estimated at 1.58 million ha or 23.9 percent of the total land area. Sparse and open forests occupy a total area of 463,842 ha or 7 percent of the land area while the total extent of well-established forest plantations amounts to 72 340 ha or 1.1 percent of the land area. The status of forest resources is given below.

Table 1. Forest resources of Sri Lanka

Forest Type Area (ha) Share of total
land area (%)
Montane Forests 3 108 0.04
Sub-montane forests 68 838 1.04
Lowland rain forests 141 549 2.13
Moist monsoon forests 243 877 3.68
Dry monsoon forests 1 094 287 16.53
Riverine dry forests 22 411 0.33
Mangroves 8 687 0.13
Sparse forests 463 842 7.01
Forest plantations 72 340 1.09
Total 2 118 939 32.02

Source: Remote Sensing Unit, Forest Department (1992)

Land use classification

According to the FAO classification, all of the above lands fall under the category of “forest”. All coconut plantations, rubber plantations and a majority of home gardens also have more than 10 percent tree crown cover and are more than 0.5 ha in extent. The total area in each category is 326,000 ha, 230,000 ha and 835,000 ha, respectively. Under normal circumstances, these lands are not considered as forests and there is no wildfire problem in these lands as well.

There are about 1.2 million ha of lands classified as “sparsely used crop lands” that are comprised of scrub and grasslands. These lands are used for upland dry cropping, mainly under shifting cultivation. These lands fall into the FAO category of “other lands”. Fires are closely associated with these lands.

Fire environment and fire regimes

The problem of forest fires in Sri Lanka can be summarized by examining weather conditions, fuel types in the forests and human attitudes in the area.

Weather

The climate of Sri Lanka is a monsoon climate. That is, weather conditions are mainly determined by the prevailing winds. There are two major monsoons, the southwest monsoon from April to July and the northeast monsoon from September to January. The southwest monsoon is stronger than the northeast monsoon and lasts longer. During the southwest monsoon rainfall is concentrated on the windward slopes of the central highlands, so on the lee side the winds are very dry. The contrary happens during the northeast monsoon, but this monsoon is weak and shorter compared to the southwest monsoon.

Based on rainfall, the country can be divided into two climatic zones, a wet zone with annual rainfall ranging from 2500 to 5000 mm and a dry zone with annual rainfall around 1000 mm. Although the rainfall figures are quite high, the distribution of rainfall is very uneven, especially in the dry zone. Much of the rainfall in the dry zone comes with the northeast monsoon during a three-month period from October to December, leaving seven to eight months virtually dry. This considerably increases the fire hazard during the dry period.

The wind pattern and topography create two marked fire seasons. There is a short but important fire season from February to March in the wet zone and a longer fire season from June to September in the dry zone. In the central highlands, only a short dry season prevails during the first three months of the year but the risk of fire is often high due to low humidity and the topography of the area.

Fire hazard

There is no significant fire hazard in most of the native vegetation of the country. The climax vegetation of the south and central highlands is tropical rain forests and sub-tropical montane forests. In the intermediate zone it is mainly evergreen forests, while in the dry zone it is tropical semi-deciduous forests. Land not occupied by permanent agriculture is mainly covered with grasses such as Imperata cylindrica and Cymbopogon spp. Fuel loads in this area are between 4-12 tons/ha (dry weight). Mean height of the grass is about one metre and grasslands are ready to burn during the dry season.

Fire hazard is very high in forest plantations, especially in eucalypt (Eucalyptus spp.) and pine (Pinus spp.) plantations. Over the past 40 years 18 000 ha of pines and 19 000 ha of eucalypts have been planted. Besides being a pyrophytic species most of the pine plantations are situated on the steep slopes of the central highlands. This situation creates a very high fire hazard.

Fire risk

The number of fires reported annually ranges from 50 to 200 depending on the prevailing weather conditions. Almost all fires reported are in forest plantations.

The area burnt by a single fire varies from 0.2 to 150 ha with an average of 10 ha. Nearly 2 percent of newly planted areas are burnt annually. Most of the forest plantations are of small size and scattered over the country. Therefore, the risk is also scattered. However, the risk of a big fire is not very high due to the small size of the plantations. Almost all fires are surface fires and crown fires are very rare.

Nearly 55 percent of all fires reported are in pine plantations while 20 percent are in eucalyptus plantations. Young plantations are more vulnerable compared to old plantations. Nearly 60 percent of all fires reported are in plantations that are less than five years of age. Very few fires last longer than 24 hours and most are in the range of 3 to 10 hours.

Main causes of forest fires

The agents causing natural forest fires, such as dry thunderstorms or volcanic eruptions, are not present in Sri Lanka. Therefore, almost all forest fires in Sri Lanka are of human origin. Carelessness seems to be the main cause. The main causes reported are:

  • Throwing cigarette butts when traveling by train or walking through forests;
  • Burning of debris by workers maintaining highways and railway tracks without taking proper precautionary measures;
  • Burning dead grass in order to obtain fresh grass for cattle. These fires often spread to nearby forests;
  • Burning of degraded forests for shifting cultivation;
  • Setting fire to the forest by hunters to drive animals out.

Major wildfire impact on people, property, and natural resources

Forest fires in Sri Lanka are of comparatively small size and occur mainly in forest plantations and grasslands. These fires rarely pose any threat to human life or property and no fatalities due to forest fires have been reported in the recent past. Most of these fires are surface fires; crown fires are very rare even in forest plantations. There is no significant health hazard associated with forest fires due to the small size and relatively short burning period. The direct economic losses are mainly due to damage to forest plantations. Environmental damage caused by forest fires is often much greater and takes many forms.

 Forest fire database

The following table shows the number of fire occurrences in forest plantations and estimated damage during 1990-2000.

Table 2. Forest fires in Sri Lanka reported during 1990-1999

 Year Total No. of Fires on Forest, Other Wooded Land, & Other Land Total Area Burned on Forest, Other Wooded Land, & Other Land
Area of Forest Burned 

 

Area of Other Wooded Land and Other Land Burned
Human Causes 

  

 

Natural Causes

 

Unknown Causes 


No. ha ha ha No. No. No.
1990 114 549
1991 100 186
1992 234 259
1993 58 174
1994 60 191
1995 126 372
1996 136 271
1997 205 610
1998 114 204
1999 47 417
Average 119.4 323.3          

       Table 3. Forest fires and economic damage in Sri Lanka, 1990-2000

Year Number of
fires
reported
Area burned
(ha)
Estimated Damage
($US )
1990 114 549 9 788
1991 100 186 15 245
1992 234 259 6 861
1993 58 174 8 204
1994 60 191 18 588
1995 126 372 19 458
1996 136 271 21 465
1997 205 610 44 958
1998 114 204 7 480
1999 47 417 42 227
2000 (up to May) 8 36 3 645

The economic loss shown in Table 3 is an estimated figure based on the cost incurred in the establishment and management of plantations up to the time of the fire.

Organizational setup

All natural forests in the country are managed by the Forest and Wildlife Departments. These forests are not prone to big wildfires. Forest plantations and “sparsely used crop lands” are the most vulnerable areas. Forest plantations are managed by the Forest Department while other lands are under the purview of different state agencies. The Forest Department is the only agency at present engaged in systematic forest fire prevention and suppression activities. Most of the activities, except awareness programs, are mainly confined to areas under the purview of Forest Department.

Forest fire management activities are handled by the Silviculture Division of the Forest Department at the national level. At the provincial level the District Forest Officers are responsible for fire control activities in their respective districts. They are assisted by Range Forest Officers and Beat Forest Officers at the village level. These officers work very closely with the village communities as well.

Fire prevention is the main strategy used in forest fire control in Sri Lanka, especially in regard to forest plantations. This is mainly done by creating firebreaks around the plantations. Interior fire breaks are also used if the fire risk is relatively high.

Village communities voluntarily involve themselves in fire suppression activities whenever the assistance is needed. However, few programmes have been developed to promote community involvement in specific areas. A new approach is being tested in pilot areas, especially in Eucalyptus and teak plantations. Each management plan contains a “participatory management working circle” under which forest user groups are formed. Following are the main features of this approach:

  1. Local communities involved in fire prevention are allowed to collect dead firewood from the plantations free of charge;
  2. The Forest Department informs the community of future forestry activities in the area so that they are aware of future employment opportunities in their locality;
  3. Agricultural and forestry activities are coordinated. This includes:
    • Finding out from villagers when they intend to burn their gardens or shifting cultivation areas so that appropriate measures can be taken to protect the plantations from fire;
    • Permitting grazing and grass cutting without charge in plantations where there is a fire risk due to a build-up of grassy vegetation.

In addition, regular fire control training is provided to these communities.

Once the trial period is over the most promising communities will be selected for formal participatory forest management programs. It is expected that the fire prevention program will be more efficient through a combination of direct involvement of the Forest Department and community participation in fire prevention activities.

Use of prescribed fire

Prescribed fire is used in forestry only in the site preparation stage. The ground vegetation is cut and burned to clear the site for planting. The area cleared this way is around 600 ha annually.

Use of fire is the standard practice in site preparation in shifting cultivation. The area under shifting cultivation is estimated to be around 1.2 million hectares. Fire is also used in other agricultural practices to a lesser extent.

Sustainable land-use practices to reduce wildfire risk

Fires escaping from agricultural lands to the forests, especially to forest plantations, has been a problem in Sri Lanka, particularly in the dry zone. Farmers are encouraged to keep the Forest Department informed when they are ready to set fire to their fields so that necessary precautions can be taken. Forest plantations, on the other hand, are somewhat protected from outside fires through the use of peripheral (and sometime internal) fire breaks.

 Public policies concerning forest fires

The current forest policy clearly states that all forests must be brought under sustainable management. Management plans have been developed for both natural forests and forest plantations and forest fire prevention is one of the activities in these plans. Depending on the status of each forest, these plans contain different strategies to be used in forest fire management.

IFFN/GFMC contribution submitted by:

K.P. Ariyadasa
Deputy Conservator of Forests
Forest Department
Battaramulla
Sri Lanka

Fax:            ++94-1-866633
e-mail:       aridas@slt.lk


Top
Country Notes
IFFN No. 26

Print Friendly, PDF & Email
WP-Backgrounds Lite by InoPlugs Web Design and Juwelier Schönmann 1010 Wien