For the most fire-prone areas of France, i.e. the Southern Départements with a typical Mediterranean climate, the area burned by wildfires has been remarkably low since 1991. This has been the longest period ever registered since data became available on fire-affected land. Although this phenomenon may be partly explained by fire prevention strategies and stringent cooperation among the different public services, it is obvious that moderate weather conditions have shown a positive impact (2).
In the 1994 fire season in France the number of fires and the area burned were distinctly reduced with 2,538 fires affecting 21,400 ha forest (0.5%), maquis and garrigue, compared with the decennial average (1980-90) of 30,600 ha caused by 3,000 fires. This result is even more satisfying when compared with the all-Mediterranean situation. In 1994 a total of 652,000 ha burned in southern Europe. The annual average for this area is 504,000 ha (1980/93). Italy and Spain both experienced severe fire seasons with 100,000 ha (1.2%) and 300,000 ha (1.1%) burned respectively. The generally satisfying French result has been overshadowed by the wildfires on the island of Corsica where 930 fires burned 16,800 ha in 1994 (6).
Fire prevention measures have been made more efficient by improved meteorological prediction and risk assessment. These actions were combined with supply of heavy equipment efforts in different forest regions with the help of the Conservatoire de la Forêt Méditerranéenne C.F.M.) in southern France and the European Union (E.U.) in other parts of France. The result: 80% of the fires were smaller than one hectare, and 95% of the fires were smaller than five hectares.
Fig.1. French Mediterranean forest area burned by wildfires duringthe period 1973-1994
In fire protection the French state services take three types of actions: (a) fire prevention education for the public, (b) surveillance of forested areas for early fire detection, and (c) vegetation management to reduce fuels (5).
(a) In the Mediterranean basin fire is traditionally used as a management tool by farmers or forest workers. Negligence (42%), accidents (27%) especially during forest utilization and agricultural activities, and arson (11%) are the main fire causes in France (1). Therefore information campaigns are organized each year in order to remind the public of the risk associated with the use of fire and the different obligations, e.g. house owners in forested areas are obliged by law to create fuel breaks with a radius of 50 m around houses.
(b) For the surveillance of forest land all state services are mobilized (gendarmerie, national police, forest service, the administration for agriculture and forestry, fire brigades, private forest owners and hunting associations). By law active fire fighting is the task of the fire brigades. In addition, a specially trained forester was created in the sixties for the Mediterranean region: the fire fighting foresters (sapeur-forestier).
In the Mediterranean climate, defined as a “red” zone of high fire risk, fire detection is primarily based on a system of fire towers throughout the region. In addition, fire spotting planes and mobile ground units of the fighters and sapeur-forestiers, equipped with water carrying four-wheel drive utility vehicles for rapid initial attack, patrol the Mediterranean forests and enforce the law. In the temperate areas of France (“orange” zone of average fire risk) fire detection is more extensive and primarily based on fire towers. To improve the surveillance and the prevention, the E.U. finances 70% of the measures in the “orange zone”.
For all actions in which the state is not directly involved a public association (Entente interdépartementale en vue de la protection de la forêt contre l’incendie) was established in 1963. This association regroups the fifteen French Départements with a Mediterranean climate. Its objectives are to inform the public, test new fire fighting equipment, train specialists, maintain special services (e.g. a water bomber air base) or fire fighting equipment (e.g. retardants).
(c) The third pillar of fire prevention is land management. Fire prevention measures, e.g. fuel breaks are planned at the scale of an entire forested area (massif forestier) without differentiating between ownerships. The private owners have to be convinced of the necessity and utility of proposed projects. In the rare case of refusal, a judicial proceeding in order to dispossess the owner is possible, but not recommended.
For hazard reduction not only classical techniques, e.g. roller-chopping, are applied, but research is carried out to develop more efficient alternatives at low costs. Moreover, prescribed burning has been introduced and a network for prescribed burning was created six years ago. The coordinator is the National Institute for Agricultural Research (I.N.R.A.).
Another approach is the support and financing of silvo-pastoral techniques in the Mediterranean forests. Grazing of cattle or sheep is temporarily permitted for local breeders. Herds of the Ariège region descend to graze in the eastern Pyrenées and the cows of the Cantal region will graze in Hérault. The most important action is the transfer of 500 heifers (young cows) from the Savoy mountains to the Maures forests near St. Tropez. In total 17,000 ha are managed with the help of silvo-pastoral techniques in Provence and Languedoc.
To complete the network of fuel breaks in the forests, the agricultural and forest services encourage the creation of green fuel breaks (coupure agricole). These are strategic discontinuities separating forested areas by interlaid cultivated fields and help to limit wildfire disasters.
The scattered construction near and in forested areas is a major problem in south-eastern France. In 1992 this led to a decree that instituted a plan of risk zones (Plan de Zones à Risque). It authorizes local communities to classify their territory in function of the fire risk into categories and to prevent construction (buildings) in wildfire prone areas or to apply restrictive measures. The communities also have to manage their domestic waste dumps in a way that prevents spontaneous combustion.
Actual Problems and Research Needs
In the last thirty years France has developed a well performing and highly competitive industry. It has a surplus of agricultural production within the European Union. In the Mediterranean area a low return on investment, high exploitation costs, low timber quality and a loosely organized wood processing industry, have created new problems for forest fire protection. Farming land is often abandoned and naturally and artificially regenerated forests cover the former agrarian countryside. Conifers, as typical pioneer species and fast growing, were favoured by this development. Since 1900 the French Mediterranean forest surface gained 220,000 ha (174,000 ha conifers) without counting the bush vegetation (6).
The question is to what extent the decreased areas burned by fires have been directly the result of better fire prevention and suppression techniques and not just of weather conditions. It is certain that wildfires of more than 500 ha are causing an increasing part of the burned area (32% in 1976, 57% during the last four years). The more effective fire protection measures seem to lead to an accumulation of fuel in the French Mediterranean forests. The policy of rapid initial attack is very effective, but does not seem to be adapted to large fires (6). Parallel to these phenomena the biodiversity of the Mediterranean ecosystems is rapidly decreasing. The traditional mosaic-shaped forests and landscapes, rich in edge-effects, provide niches for rare and endangered flora and fauna. Here, prescribed fire for hazard reduction and silvo-pastoralism for conserving the traditional landscape might offer an appropriate solutions. (For more details on the use of prescribed fire in France: See last issue of “Informations D.F.C.I.”, the fire newsletter of CEMAGREF (Address: CEMAGREF, Le Tholonet, B.P.31, F-13612 Aix-en-Provence, the Editor.)
Forest Fire Research
Mediterranean forests are characterized by complexity and fragility. Their management with the objectives of protection, production and biodiversity necessitates the mastering of especially adapted techniques. The actual French research programmes aim to define the different vulnerable zones of the Mediterranean forest corresponding to soil characteristics, vegetation and relief. Different research projects funded by the European Union and international contracts show that scientific cooperation is considered as essential.
At the moment the knowledge about “traditional” preventive measures, (e.g. surveillance, fuel breaks) and modern fire fighting techniques, are relatively advanced in France. The introduction of Geographical Information Systems (GIS) in combination with more sophisticated satellite data have fostered fuel mapping and forest fire modelling projects and expert systems. While the basic characteristics of fire physics are known under controlled conditions, little research has been achieved to document fire behaviour and effects. Additional research is needed to better predict the behaviour and effects of prescribed burning and wildfires.
The Mediterranean forest research division at I.N.R.A. with its forest fire prevention unit (prévention des incendies de forêt) in Avignon concentrates its research on (a) modelling of flammability and fire propagation, (b) traditional and new hazard reduction methods for fuel breaks, including modelling of vegetation dynamics on fuel breaks, and (c) effect on trees of surface fires and convective activities in prescribed fires.
The École Nationale des Mines is investigating digitized cartography of fire prone zones. The National Centre for Scientific Research (C.N.R.S.) and various universities are working on the different aspects of fire ecology, e.g. plant succession after fire. Remote sensing of savanna fires and determination of gaseous and aerosol emissions is one of the major research activities conducted under the umbrella of IGBP/IGAC.
The National Centre for Agricultural Machines, Rural Engineering, Water and Forestry (Centre National du Machinisme Agricole, du Génie Rural, des Eaux et des Forêt) provides access to an important documentation on forestry and forest fires in the Mediterranean basin.
(1) Alexandrian, D. and Gouiran 1900. Les causes d’incendie – Levons la voile. R.F.F., XLII N° sp., p. 36.
(2) Hertier, J.-P. 1993. Forêt méditerranéenne: vivre avec le feu? Eléments pour une gestion patrimoniale des écosystèmes forestiers littéraux. Les Cahier du Conservatoire du littoral. N° 2, 147 pp.
(3) Meteo France 1994. Les conditions métérologiques de l`été 1994. Forêt méditerranéenne. XV, N° 4, p.427-431.
(4) Ministère de l`Agriculture et de la Peche 1994. Forte réduction des surfaces de forêts brûlées. Communiqué de presse.
(5) Ministère de l`Agriculture et de la Peche 1995. Les feux de forêt en 1994. Direction de l’espace rural et de la forêt. Bureau de la protection de la forêt. 3 pp.
(6) Turlan, T. 1991. Les incendies de forêt en région méditerranéenne. Stratégies de prévention et évolution du phénomène. Diplôm d’Agronomie Approfondie, Dijon; 93 pp.
From: Stefan Teusan Address: Equipe Préventation des Incendies de Forêt Institut National de la Recherche Agronomique Avenue A. Vivaldi F-84000 AVIGNON