Paysages du feu

Paysages du feu

© Gilles Cllément

Extraits de l’article de Gilles Clément, Véronique Mure et Jordan Szcrupak pour l’ouvrage « Feu » (Ed. Dunod – Cité des Sciences et de l’Industrie , 2018).

 

Comme la pluie et le vent, le feu s’adresse à tous

Gilles Clément.

Depuis des millénaires, le feu, qu’il soit naturel ou d’origine humaine, façonne les paysages méditerranéens. Jusqu’à la première moitié du XXe siècle, l’homme l’a considéré comme un allié dans la gestion du territoire.

Brûler la garrigue épineuse pour favoriser la repousse de l’herbe à mouton, le Brachypode rameux, était une pratique nécessaire à la bonne gestion des pâturages. Soumises périodiquement au passage du feu, de nombreuses espèces végétales ont appris à lui survivre, voire à en tirer avantage. Ainsi, la liste des pyrophytes de la garrigue et du maquis est longue et les adaptations variées. L’asphodèle, le Brachypode rameux, le Chêne kermès, le Chêne vert, l’arbousier, le pistachier, la bruyère, et bien d’autres repoussent rapidement après le feu grâce à des organes souterrains profonds ; le Chêne-liège se protège des flammes avec une écorce épaisse ; le Pin d’Alep et les cistes misent, nous l’avons vu également, sur une stratégie de recolonisation, la dormance de leurs graines étant levée sous l’effet du choc thermique ou sous l’effet des fumées.

Comprendre les pyro-paysages pour jardiner avec le génie naturel •

Au-delà de la flore des rives de la Méditerranée, de telles adaptations sont caractéristiques de tous les écosystèmes soumis au climat méditerranéen dans lesquels chaleur et sécheresse estivales créent les conditions idéales pour la propagation du feu, souvent renforcées par la présence d’un vent fort.

Si les stratégies végétales en jeu dans ces écosystèmes font l’objet de l’attention des forestiers et écologues méditerranéens depuis longtemps, Gilles Clément sera l’un des premiers paysagistes-jardiniers à s’en emparer dans ses projets, révélant ainsi au grand public l’intérêt écologique des « paysages du feu ». Pour lui, la « singularité du biome méditerranéen au sein du jardinage planétaire vient du feu en tant que mécanisme naturel répété, induisant au fil du temps une pyro-flore adaptée, voire même appelant le feu pour assurer sa régénérescence ». Une singularité qu’il met en scène dans les années 1990, dans un « jardin du feu », le jardin des Méditerranées, au domaine du Rayol, sur la côte varoise.

(…)

Loin de considérer le feu comme un élément destructeur, Gilles Clément l’envisage comme créateur de paysages et allié du jardinier. Et si les flammes ne parcourent pas les pentes du domaine du Rayol, bout de terre enclavé dans un urbanisme dense, un jardinage adapté en compense l’absence. Ici, les graines des cistes sont chauffées quelques secondes dans une poêle, tandis que celles des restios (Elegia capensis), originaires d’Afrique du Sud et semblables à de grandes prêles, sont mises dans un sac puis enfumées, tout comme le ferait un apiculteur pour manipuler les ruches. Inspirées des effets des feux de forêt, ces deux pratiques sont utilisées pour lever la dormance des graines avant d’être semées.

(…)

Le feu anime notre désir de paysage(s) • Pour autant, la relation de notre société urbaine avec un feu qualifié de « risque majeur » n’est pas apaisée. Les grands incendies estivaux, par leur ampleur, leur intensité et leur fréquence accrue, affectent les capacités de résilience des écosystèmes, compliquent la lutte, et réveillent des réactions passionnées.

Si les feux de forêt, avec les inondations, constituent l’expression majeure d’un phénomène naturel à l’échelle du territoire méditerranéen, ils bouleversent notre expérience de « paysage ». Le choc de la disparition brutale d’un paysage familier émeut. Les étendues noircies, que l’on perçoit comme dévastées, focalisent tous les regards. L’après incendie est alors propice à l’expression de revendications paysagères. De cette émotion, exacerbée par une médiatisation forte, naît le sentiment général de disparition de la forêt méditerranéenne. Contrairement aux idées reçues, comme nous l’avons vu, la forêt ne disparaît pas en France : elle gagne du terrain chaque année. Sur la rive nord de la Méditerranée, depuis le début du XXe siècle, l’abandon des cultures en terrasses et de l’exploitation des chênes verts, associé à la disparition du pâturage, laisse la place au retour de la forêt qui modifie le paysage de façon sensible. Mais sommes-nous en mesure de percevoir ce développement forestier qui referme les paysages du quotidien ? Un développement qui se calcule en unités de surface, mais également en volume. Le bois n’étant plus exploité, l’accroissement de la biomasse qui en résulte amplifie la vulnérabilité des forêts à l’incendie.

Dans le même temps, voire plus vite, la ville, dépourvue de sa ceinture agricole, s’étend au contact des espaces boisés. L’habitat dispersé en milieu forestier focalise alors la défense des biens et des personnes. C’est ainsi que l’on est passé de la protection de l’espace naturel à la protection civile.

Habiter le territoire du feu • Questionnée par la multiplication et l’amplification des incendies estivaux sur la côte méditerranéenne française, une nouvelle génération de paysagistes s’est emparée de la question. Imprégnés des théories de Gilles Clément sur les dynamiques de ces paysages de transition, ils proposent de considérer l’incendie non plus comme un risque, mais comme une ressource créative pour les territoires, permettant de dépasser la diabolisation du phénomène en augmentant notre compréhension collective de l’écologie du feu ; permettant également d’intégrer à la réflexion d’autres domaines d’intervention tels que l’urbanisme, l’agriculture, l’énergie, le tourisme et la santé, tous étroitement liés aux biens et aux services que procurent les milieux forestiers méditerranéens. C’est sur ce défi d’aménagement du territoire que le projet de paysage ouvre la réflexion vers un nouvel « urbanisme de l’inflammabilité », au sein duquel le feu devient le véritable moteur d’une nouvelle façon de vivre le risque.

(…)

… retrouver la totalité de l’article dans le l’ouvrage « Feu », de Nadine Ribet
, avec la collaboration de Vincent Bontems, Danièle Escudié et Éric Rigolot, publié par les Editions Dunod et la Cité des Sciences et de l’Industrie (2018), ou lire un autre extrait ici.

Démonstration de brûlage dirigé au Domaine du Rayol ©Véronique Mure

Feu d’entretien en Australie ©Gilles Clément

Un an après l’incendie, Sandy Bay Afrique du Sud. ©GillesClément

3 mois après le feu St Florent 22 ©VéroniqueMure

3 mois après le feu St Florent 22 ©VéroniqueMure

© veronique mure

LANDSCAPES

« Just like the rain and the wind, fire is for everyone » (Gilles Clément).

For thousands of years, fire, whether natural or caused by man, has shaped Mediterranean landscapes. Until the first half of the twentieth century, man considered it an ally in the management of the land.

Burning the thorny scrubland to promote the regrowth of mutton grass, Brachypodium retusum, was a necessary practice for the proper management of pastures. Periodically submitted to the passage of fire, many species of plants have learned to survive it or even take advantage of it. Therefore, the list of pyrophytes of garrigue and maquis shrubland is long and there are many adaptations. The Asphodel, Brachypode Retusum, Kermes Oak, Green Oak, Arbutus, Pistachio, Heather, and many others grow back quickly after a fire thanks to their deep underground organs; Cork Oak protects itself from the flames as we have seen above, with a thick bark; Aleppo pine and Cistus rely, as we have seen, on a strategy of recolonization, the dormancy of their seeds being lifted under the effect of thermal shock or smoke.

Understanding pyro-landscapes for gardening with natural genius

Apart from the flora of the shores of the Mediterranean, such adaptations are characteristic of all ecosystems with a Mediterranean climate in which the summer heat and drought create the ideal conditions for the spread of fire, which is often reinforced by the presence of a strong wind.

Although the plant strategies involved in these ecosystems have attracted the attention of foresters and Mediterranean ecologists for a long time, Gilles Clément was one of the first landscapers/gardeners to use it in his projects, introducing the ecological interest of « fire landscapes » to the general public. For him, the « unique feature of the Mediterranean biome in planetary gardening comes from the use of fire as a natural repetitive mechanism, inducing a suitable pyro-flora over time and even using fire to ensure its regeneration ». He showcased this unique feature in the 1990s in his « garden of fire », also known as the Mediterranean Garden, in the Rayol area on the Var coast. This garden brings together, over an area of seven hectares, all of the world’s Mediterranean landscapes that are able to co-exist with fire. The most emblematic species have been brought together to compose not just a botanical garden but « paintings of life » that take visitors on a journey to the heart of a biological question: how is it possible to co-exist with fire? Cistus is honoured in the maquis section, whilst in the South African garden visitors can discover protea, typical of the fynbos (a plant formation related to the maquis of the Mediterranean regions), which has woody fruits that only release their seeds under the effects of fire. The bush of the Australian garden contains mimosas and eucalyptus of which part of the buried trunk allows them to regenerate very quickly by rejections after a fire. But it is certainly theblackboys(Xanthororea pressi), the large chunky grasses of the Australian Kwongan, that are the most symbolic of these pyro-landscapes. With their protective armour, blackened by the repeated passages of the fires, they keep the mark of fire indelibly within them.

The Aleppo pine has chosen fire

The Aleppo pine is a pyrophyte. Everything in the tree calls for fire, which it needs in order to reproduce. A destructured crown that lets light in, allowing the development of a fluffy layer of shrub in the undergrowth and dry needles are stored in a tangle of dead branches all along the trunk – the Aleppo pine do not self-prune… The result: this tree is a « fire ladder », a species that promotes fire to facilitate its reproduction because its serotinous cones, coated with a wax, open only under the effect of heat. It is therefore only after the passage of a fire that the seeds will be released and will find, on top of the warm layer of ashes, a favourable environment for their germination, thus regenerating the pine forest.

Far from considering fire as a destructive element, Gilles Clément considers it a creator of landscapes and an ally of the gardener. And although flames are not allowed to roam the slopes of the Rayol area, a piece of land surrounded by a dense urban development, suitable gardening compensates for its absence. Here, the seeds of the Cistus are heated for a few seconds in a pan, whilst those of Horsetail Restio (Elegia capensis), native to South Africa and similar to large horsetail, are put in a bag and smoked, just as a beekeeper would do to handle their hives. Inspired by the effects of wildfires, both of these practices are used to lift the dormancy of the seeds before they are sown.

Now an emblematic site for worldwide pyro-landscapes, the Mediterranean Garden contributes to their knowledge. Visitors discover that there are plants that are accustomed to living with the pressure of fire and that in fact fire can be a creator of richness by rejuvenating breathtaking plant formations and by recreating diversity among the ecosystems to reform the mosaic of environments that is so characteristic of Mediterranean landscapes, from meadows to area of mixed oaks (several species belonging to the genusQuercus), whilst passing through the various stages of garrigue or maquis.

Fire animates our desire for landscape(s) •However, the relationship of our urban society with fire, which is considered a « major risk », is not harmonious. Large summer fires, due to their scale, intensity and frequency, affect the resilience of ecosystems, are difficult to fight and provoke passionate reactions.

Although forest fires, along with floods, constitute the ultimate expression of a natural phenomenon on a large scale within the Mediterranean territory, they disrupt our experience of the « landscape ». The shock of the sudden disappearance of a familiar landscape moves us. We focus our eyes on the blackened expanses, which are perceived as having been devastated. The period after the fire is therefore conducive to the expression of demands related to the landscape. This emotion, exacerbated by large amount media coverage, creates a general feeling that the Mediterranean forest is disappearing. Contrary to popular belief, as we have seen, the forest is not disappearing in France: it is gaining ground every year. On the north shore of the Mediterranean, since the beginning of the twentieth century, the abandonment of terraced fields and the exploitation of Holm Oak trees, together with the disappearance of grazing, has left room for the return of the forest which is changing the landscape in a significant way. But to what extent are we able to perceive this development of the forest that is changing our everyday landscapes? A development that is calculated in units of surface area, but also in volume. As their wood is no longer used, the resulting increase in biomass increases the vulnerability of forests to fire.

At the same time, even more quickly, the city, devoid of its agricultural belt, is extending and entering into contact with wooded areas. The scattered habitation in the forest means that the defence of property and people has become the priority. This is how we went from protecting the natural environment to protecting the population.

Living in the territory of fire •Questioned about the increasing number and size of summer fires on the French Mediterranean coast, a new generation of landscapers has taken on this issue. Steeped in Gilles Clément’s theories about the dynamics of these transitional landscapes, they propose ceasing to consider fire as a risk but rather as a resource that can be used creatively for the territories, enabling us to overcome the demonization of the phenomenon by increasing our collective understanding of the ecology of fire; this approach also makes it possible to integrate other areas of intervention such as urban planning, agriculture, energy, tourism and health, all of which are closely linked to the goods and services provided by Mediterranean’s forests. It is with regard to this challenge of spatial planning that the landscape project promotes reflection on a new « urbanism of flammability », in which fire becomes the real engine of a new way of managing risk.

This approach assumes that it is neither culturally nor politically feasible to avoid the risk of fire but that there is an opportunity to better share responsibilities and anticipate crisis situations in order to reduce vulnerability to fire. Current prevention models attempt to systematically prevent all fires from starting, through both the preventive clearing of exposed areas and active control. However, to preserve the mosaic of Mediterranean environments we should not just aim to extinguish all forest fires but rather learn to coexist with them, adjusting the city to the ecological processes of which fire is a part.

For landscapers, the figure of thegardenis considered complementary to traditional urban culture in the Mediterranean. It is a sensitive area inherited from a local mentality. It borrows the common sense of the peasant: the art of manipulating the flow of water and the composition of living plants taking into account the features of the location (climate, soil, and flora). By adjusting this culture today to take into account advances in weather modelling and forecasting tools, this expertise is helping to improve city planning strategies and provide new, smarter, stronger and more territory-based relationships. Starting from the premise that we inhabit the territory of fire, defining a landscape project aimed at reducing vulnerability to it means recognizing the complexity of the phenomenon and dealing with new cultural and spatial relationships. Reflecting on the « urbanism of flammability » requires the reorganization of interfaces between inhabited areas and the forest and city planning. Unlike civil engineering, whose solutions aim to guarantee the protection of urban infrastructures and to organize the intervention of rescuers in the event of a crisis, the objective of the landscape project is to organize the whole of the territory by proposing to act on the conditions that regulate the intensity of the phenomenon. Changing the way that we look at fire makes it possible to go from a defensive culture to project experiences that take into account the short-term effects of a fire on the vulnerability of the city and which in the long-term rearrange the legitimate geographical area of fire in the collective construction of an inhabited area. This leads us to think differently about the organization of the « greater landscape » and, at the same time, to adapt the planning of tomorrow to anticipate the effects of climate change.

After the fire, a new landscape is revealed

A well known phenomenon in the South of France is that the fire unveils (and sometimes reveals) a new landscape. In 1989, when nearly 60,000 hectares went up in smoke, a fire ravaged part of the Mont d’Or, a beautiful round hill near Manosque. Amongst its calcinated brambles, olive trees appeared. The reduction in the number of farmers on the plain, as well as the strong frosts of 1956 and 1981, had led people to forget about the presence of the tree of peace on the terraces of Mont d’Or. The Luberon Regional Natural Park and the commune have since begun an operation to rehabilitate theolivettes, small plots planted with olive trees for family consumption. It is therefore the fire, which was considered devastating, that triggered the process of revival of the terraces which, in addition being of economic, landscape and historical interest, provide fire protection by constituting an effective fuel cut.

 

 

Il n'y a pas de commentaires