The dry season starts two to three weeks after the rains end in northern Sudan, i.e. November to April/May. Tall and short grasses are increasingly desiccated during the dry season. Increased wildfire hazard is associated with low humidity, high fuel loads and the presence of moving graziers. Annual wildfires are common and spread rapidly due to northeast winds and flat terrain. This is the case in central, western and southern Sudan. Repeated fires occur if the hot dry weather continues, i.e. late rains.
Ecological role of forest fires
In the high-rainfall savannah ecosystems of southern Sudan fires kill certain fire-sensitive trees, e.g. Isoberlinia doka, Daniellia oliveri, etc. and reduce the growth of other species. Fires may reduce gum yields from Acacia senegal by up to 50 percent. This is considered a big economic loss. In an average year fires affect about 70 percent of the open rangelands.
Fires may also encourage the spread of some species, e.g. Acacia mellifera in central Sudan on clay soil where the “Acacia-grassland cycle” takes place. The occurrence of Acacia alternates with tall grasses. Acacia takes over if the fires are of low severity. Grasses become dominant with increasing fuel loads and high-intensity fires.
Impacts of wildfires
Lightning fires or fires caused by nomads often damage or destroy whole villages with huts that are built from grass and wooden materials. This problem is very common in central Sudan. Villagers in many instances are caught by surprise.
Fires statistics for the period 1980 to 1999 are lacking except for limited incidents in Jebel Marra where some 3 000 feddan (1 feddan = 0.42 ha) of Cypressus lusitanica were destroyed in the 1990s. Large tracts are often swept over by wildfires in central and western Sudan. Nothing is presently known of the situation in southern Sudan where fires are presumably set by the army to improve visibility and for control of the terrain. More than 60 million ha are affected annually.
A fire management organization is not in place. However, the traditional system of constructing or maintaining forest fire lines (firebreaks) is adhered to through an annual budgeted program , but funds are always short. Surface vegetation, especially grasses, may dry very quickly after the end of the rainy season and the firebreak programme is never completed in time.
By law, fire lines are supposed to form the boundaries and protect Government forest reserves. The law states that fire lines should be at least two metres wide but these are inadequate and normally five- to eight-metre-wide lines are cleared, but fires may still jump over. Cleaning fire lines is an expensive operation.
In colonial times and up to the end of the 1960s the Native Administration, under the supervision of the Range and Pasture Department and in close collaboration with the Forestry Department, maintained a firebreak network extending north-south over North Kordofan and North Darfur to protect grazing lands and gum gardens. Usually four-metre-wide lines are cleaned and spaced parallel to each other and separated by an 80 m wide area that is burnt just before the end of the rains. This pattern is repeated systematically over the semi-arid lands. Early warning, detection and monitoring systems are not available. No volunteer fire fighters are available but people and communities are obliged by the forest law to report and help fight wildfires. Fire research is absent.
Use of the prescribed fires
Prescribed burning is used in natural forests in western Sudan (Jebel Marra) and used to be practised as early burning in southern Sudan but stopped due to the war. The use of backfiring for controlling wildfires is forbidden except for certain conditions and under control of appropriately trained foresters.
Sustainable land use practices to reduce wildfires
Very wide fire lines (50 m) have been used to separate blocks of Eucalyptus plantations in the Khartoum green belt. Fuelbreaks (greenbelts) consisting of teak (Tectona grandis) were used in the south to protect fire-prone species. In traditional agricultural areas, people and farmers are guided by extension workers to protect their villages and lands. At present there is no method other than burning to clear forest lands for cultivation. The forest law, however, prevents wasteful burning and obliges cultivators to make use of cleared woody material (shrubs, trees) by converting it into useful products, e.g. charcoal.
Public policy concerning fires
The forest policy of 1986 emphasizes the protection of forests against fire. The forest law of 1989 prohibits trespassing of people and their animals into reserved forests and prohibits the carrying of ignited material into the forests, making fires for cooking or other purposes in or near forests and obliges people to help extinguish forest fires.
Reduction of fires will definitely conserve the natural resources of the country and will improve the growth of many tree species.
Fire management needs cannot be detailed here due to the complexity of the different environmental conditions and the need for different management techniques. The very large size of the country, the various local factors and weather conditions, the trend toward repeated severe droughts and desertification, the increase in population and domestic animals, the displacement of rural people to cities, the expansion of unplanned rain-fed cultivation, the poverty of the people and the lack of knowledge of decision makers regarding forest conservation are all major problems and impediments.
Sudan needs extension capability to teach people how to protect their lands. Research is needed to find safer methods to prepare land for agriculture or forest plantations. Above all, trained personnel and supporting equipment are needed for transport, detecting and fighting forest fires.
Goldammer, J. G. 1991. Integrated fire management, Jebel Marra Forest Circle (Sudan). Report for GTZ P.N. 86.2595.6-01.100.
Abdel Aziz M. S. Bayoumi
Faculty of Forestry
University of Khartoum