J. K. Ndambiri & C.D. Kahuki
Forest Department, Nairobi, Kenya
Fire Environment and Fire Regimes in Kenya
Kenya has a total land area of 582 646 km2. Highlands form most of the south-west and central parts and are well watered and fertile. More than 70 percent of Kenya is a climate condition classified as both arid and semi-arid; and characterised by low biological activity.
The country’s forests are concentrated in the moist central highlands where the human population and agricultural production are also found. In the extensive semi-arid region, forests are situated on isolated hills and in discontinuous narrow bands along river beds.
Kenya gazetted forests comprise some 1.64 million hectares of land (about 3 percent of the land area). Outside the gazetted forests, there are other large tracks of forests in trustlands, i.e. national parks, national reserves and privately owned land covering about 0.5 million hectares in the following regions:
• Coastal forest region
• Dry zone forest region
• Mountain forest region
• Western Mau forest region
Because of extended degradation of the closed forests, a programme of plantation establishment was started in 1946. Cutting of the valuable natural hardwood is considered non-sustainable and has been banned. The wood industry relies on softwoods from government forests.
Forest Fire Management
Most of the forests, especially the highly productive ones, including both indigenous and plantations, are located in the relatively high fire-prone areas. Wildland fires continue to be one of the biggest threats to forests. A forest fire protection unit exists with the Forest Department. A conservator of forests is appointed at the Headquarters who:
• Plans, organizes, equips, trains and provides a follow up supervision of a cost effective fire pre-suppression and suppression organization at all levels with the Forest Department.
• Develops a comprehensive nation-wide program designed to create awareness of the need for fire protection and control.
• Plans the implementation of risk and hazard reduction programmes.
In the field, District and Station Forest Officers organize and supervise forest fire prevention and suppression activities within their areas.
Available firefighting equipment includes, vehicles, tractors, pump units with hoses, knapsack sprayers and hand tools.
Firebreaks and forest boundaries are established and maintained on a regular basis to keep fires from spreading between plantations and from neighbouring settled reserves.
Fire detection is carried out by ground patrols and permanent stations (fire towers). A few of them have radio systems, vehicles, motorcycles and bicycles. When a fire occurs a comprehensive fire report is compiled detailing the location, area burnt, suppression cost and the actual damage to the forest.
Forest Fires Statistical Data
Table 2-10 Number of fires and area burned in Kenya for the period 1990 – 1999.
Area burned (ha) Number of fires
Year Plantations Indigenous Bush/grass
1990 85 331 12 183 36
1991 1 705 236 6 697 64
1992 6 170 5 494 13 302 180
1993 1 731 515 1 718 48
1994 690 69 1 913 40
1997 4 726 2 961 7 729 121
1999 1 449 317 2 041 59
All fires in Kenya are started by people. Of these fires, 40 percent are classified as arson, 20 percent are caused by negligence and carelessness and 40 percent are due to unknown causes.
Community Involvement in Fire Management Activities
Campaigns through public meetings are organized before the declaration of the fire danger season to create awareness for the need to prevent any forest fires and action to be taken in case a fire is detected.
Fire Ecology and Management Research
A fire research programme conducted on the Lewa Wildlife Conservancy since 1992 increased understanding about the effects of type and intensity of fire on savannah vegetation in the central highlands of Kenya. Techniques for assessing range condition were developed to assess the condition of the vegetation and these were used to monitor and assess the effect of the controlled burns applied on the Conservancy during 1997 and 1998. The vegetation in this area is in the range type called Scattered Tree-Grassland (Acacia-Themeda) rangeland. The study during 1998 tested the fire intensity model developed for southern African savannahs (Trollope 1998). The study also determined the effect of type and intensity of fire on the mortality and topkill of stems and branches of different tree and shrub species occurring in the aforementioned range type.
The results of the research on the fire ecology of the savannah vegetation on the Lewa Wildlife Conservancy led to the following general conclusions regarding the effect of type and intensity of fires on the tree and shrub vegetation:
• Generally the mortality of trees and shrubs is very low irrespective of type or intensity of fire, i.e. 4.4 percent;
• Generally all the bush species were highly resistant to fire and the only woody species that consistently suffered a high mortality with burning was Acacia nilotica;
• Head fires burning with the wind caused a greater topkill of stems and branches of trees and shrubs than back fires burning against the wind. This difference increased significantly for bush greater than three metres in height;
• Increases in fire intensity caused a greater topkill of bush while increases in the height of trees and shrubs resulted in a lower topkill of bush;
• Cool fires that will cause a significantly lower topkill of bush can be obtained by burning in the late afternoon/early evening when the air temperature is <20°C and the relative humidity >50 percent;
• High intensity fires that will cause a significant topkill of bush can be obtained by burning during the heat of the day from noon onwards when the air temperature is >20°C and the relative humidity <30 percent.
Remark: Several facts and references were added by J. Goldammer, Global Fire Monitoring Center (GFMC).
Cwielong, P., Fedlmeier, C. & Schülzke, R. 2000. The culture of fire on southern Africa. An example of Lesotho and Madagascar. An interim report of the Working Group Forest Technology. Int. Forest Fire News 23 (in press).
Trollope, W.S.W. & Trollope, A. 1999. Fire ecology of the savanna vegetation on the Lewa wildlife conservancy in Kenya. Department Livestock and Pasture Science, Faculty of Agriculture, University Fort Hare, Alice, 5700, South Africa (mimeo).
Uvoo, A.D. 1996. The management and role of fire in forestry management and development in Kenya. The state of forest research and management in Kenya. Proceedings, June 1996, Muguga, p.127-129.
Ndambiri, J.K. & Kahuki, C.D. 2001. The fire situation in Kenya. Int. Forest Fire News 25.