What is a primeval forest?

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Primeval forests first appeared on our planet in the Devonian Period, 380 million years ago. They were very tall, magnificent and abundant with animal and plant life.

Before the appearance of the human species 40,000 years ago, all of the Earth’s forests were primeval. Humans have been clearing, exploiting and deforesting them at an ever increasing rate.

A primeval forest is a forest that hasn’t been exploited or cut down by man. If it has been in the past, then a sufficient amount of time has elapsed for the forest to become primeval again.

In humid tropical or equatorial zones, where trees grow all year round, it takes seven centuries for a cleared area to be reclaimed by a primeval forest. In temperate zones, where trees only grow five or six months a year due to winter, it takes about ten centuries.

In a lowland tropical primeval forest, trees are tall (50-70 meters in height, or approximately 164-230 feet) and the undergrowth is dark because the canopy – the upper layer of trees – intercepts up to 98% of sunlight. (Light is abundant on the canopy, where 75% of the fauna is found. It is very humid because it rains during the day, and a blanket of mist covers the undergrowth at night – all year long.

The darkness of the undergrowth is sometimes cleared due to windthrow. This can affect close to a hectare (2.5 acres) of land when a large tree collapses and its vines drag the neighboring trees down with it. Windthrow is useful to the renewal of the primeval forest. By bringing light back to the undergrowth, windthrow allows pioneer trees to grow in turn and the forest begins a new cycle. The gigantic fallen trunks decompose over the course of a few months, sheltering a wide variety of fauna and nourishing the soil.

Forest wildlife is often hard to see in the daytime, but it is always noisy. It is most silent at the hottest hour of the day and loudest at night. It is also easier to observe wildlife in the undergrowth at night, as different zoological groups gather on the canopy, producing a nocturnal concert: aboreal amphibians, cicadas, nocturnal birds, hyraxes, etc. The birds’ songs get very loud just before dawn.

Lowland tropical rainforests represent the maximum of the the world’s biological complexity and diversity; almost all living groups are represented there. There is also a paradox with regard to trees: rare species are ubiquitous whereas common species are scarce. In equatorial forests, one often has to travel several kilometers to find two trees of the same species, and inventories of 100 different tree species per hectare are common. It is impossible for humans to /manage/ this kind of biodiversity, and to be effective we must adopt a collective approach.

The primeval forests of the equatorial plains are located in the Amazon, Indonesia, Melanesia and the Congo Basin. With 90% of its territory covered by primeval forests, French Guiana is home to one of the largest regions. Another paradox is that no matter where these forests are, they all look the same – the same massive tree trunks, the same light, the same sounds and the same smells – and yet, all of their plant and animal species are different from one continent to another.

Whether it be in Africa, America or Asia, the human populations of tropical primeval forests have never destroyed them or altered their primeval nature. Deforestation in these regions is akin to genocide, because without their forests these populations are deprived of their daily resources, shelter, culture and often times, their lives.

Temperate lowland primeval forests are found in British Columbia and along the western coast of the United States, Tasmania, New Zealand and the Southern Cone of South America. In Europe, very few lowland forests have been preserved from exploitation. Poland’s Białowieża Forest is the oldest, having formed 10,000 years ago during the last ice age. It is also is one of the last remaining primeval forests in Europe and a haven for some of the continent’s last bison still alive. It is extremely beautiful.

Once a tropical or temperate primeval (or primary) forest has been destroyed, a secondary forest develops, with very limited biodiversity at first that increases over time, provided no predationf/ occurs before it grows back into a primeval forest.

According to the UNEP (United Nations Environment Programme), more than 80% of the world’s original forests have been cut down in the last century. Every year, 15 million hectares of primary tropical forest – the size of England – are deforested. Trees absorb carbon dioxide, release oxygen and purify the atmosphere. We wouldn’t be able to breathe without them because photosynthesis is our only source of oxygen. Without trees, the human species would be in grave danger.

Given these circumstances, the restoration of a primeval forest in a densely populated area like Western Europe could be a way of reconnecting with a sense of time and the long life-cycles of trees, while reconciling man with unspoiled nature.

La forêt tropicale humide de plaine est le sommet mondial de la complexité et de la diversité biologique ; presque tous les groupes vivants y sont représentés. Il existe un paradoxe en ce qui concerne les arbres : les espèces rares sont omniprésentes et les espèces communes sont rares. Dans les forêts équatoriales, parcourir plusieurs kilomètres est souvent nécessaire pour trouver deux arbres d’une même espèce ; des inventaires de 100 espèces d’arbres par hectare sont fréquents. Il est impossible pour un esprit humain de dominer cette biodiversité et seule une approche collective est efficace.

Les forêts primaires des plaines équatoriales sont en Amazonie, en Indonésie, en Mélanésie et dans le bassin du Congo. La Guyane française, avec 90 % de forêts primaires sur son territoire, représente l’une des zones les plus vastes. Un autre paradoxe : où qu’elles soient, toutes ces forêts se ressemblent – mêmes énormes troncs, mêmes lumières, mêmes sons et mêmes odeurs – pourtant, qu’il s’agisse de plantes ou d’animaux, toutes les espèces sont différentes d’un continent à l’autre.

Que ce soit en Afrique, en Amérique ou en Asie, les populations humaines des forêts primaires tropicales n’ont jamais détruit celles-ci, ni modifié leur caractère primaire. Dans ces régions, la déforestation peut être assimilée à un génocide car sans leurs forêts ces populations perdent leurs ressources quotidiennes, leurs abris, leurs cultures et souvent leur vie.

Les forêts tempérées primaires de plaine se trouvent, quant à elles, en Colombie-Britannique et le long de la côte Ouest des États-Unis, en Tasmanie, en Nouvelle-Zélande et dans le cône Sud de l’Amérique du SudEn Europe, très peu de forêts de plaine sont restées indemnes de toute exploitationLa forêt de Białowieża en Pologne est la plus ancienne ; c’est l’une des dernières forêts primaires d’Europe, formée il y a 10 000 ans lors de la dernière glaciation. Elle est le refuge des derniers bisons d’Europe ; et elle est aussi de très grande beauté.

Après la destruction d’une forêt primaire, qu’elle soit tropicale ou tempérée, une forêt secondaire se met en place, avec une biodiversité initiale très réduite mais qui augmente avec le temps, à condition toutefois qu’aucune prédation n’intervienne avant le retour à la forêt primaire.

D’après l’UNEP, le programme des Nations Unies pour l’environnement, plus de 80% des forêts originelles ont été abattues au cours du siècle dernier ; chaque année 15 millions d’hectares de forêts tropicales primaires, soit la superficie de l’Angleterre, sont déboisés. Sans les arbres, qui absorbent du gaz carbonique, rejettent de l’oxygène et purifient l’atmosphère, nous ne pourrions pas respirer car la photosynthèse est notre seule source d’oxygène, et l’espèce humaine serait alors gravement menacée.

Dans ces conditions, le retour à une forêt primaire dans une zone densément peuplée comme l’Europe de l’Ouest pourrait être une façon de renouer avec le temps long qui est celui des arbres et de réconcilier l’homme avec la nature intacte.

© Jessica Buczek
© Jessica Buczek
dessin de Francis Halle
An unidentified tree - Peruvian Amazon. Drawing by Francis Hallé

Why a primeval forest?

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Most of the large countries located in temperate latitudes – the United States, Canada, Chile, Russia, China, Japan, South Africa, Australia, New Zealand – have managed to conserve primeval lowland forests, whereas in Western Europe our ancestors destroyed them, unaware that they had irreplaceable ecological value; in Europe only one remains, that of Białowieża in Poland, which is, alas, under threat to its very existence, despite reminders to do so from the European Union.

The association was set up on the premise that it was unacceptable for Europe to be left with nothing but tree plantations and secondary, exploited, artificial forests with degraded biodiversity. Our aim is to create the conditions for a return to lowland primary forest in Western Europe, with the high biodiversity that was characteristic of our regions before they were deforested.

In the current context of dramatic degradation of the planet’s biodiversity and massive greenhouse gas emissions, such a project is, on its own scale, a major issue of general interest. Added to this is the exceptional scope it would open up for scientific research.

Where will this project be located? The question is under study, and we have already accepted that it should be cross-border, and therefore European.

Our project is ambitious, both in terms of its size and its timeframe.

The area, 70,000 hectares, corresponds to that of the Polish part of Białowieża; it is necessary because of the presence of large European forest fauna.

While this can take up to 10 centuries, it depends on the age of the original forest; this is the time needed for forests to reappear in regions with cold winters where trees only grow for five or six months a year, and no one can reduce this time or speed up the process. A return to a high level of biological diversity requires us to take the long view of nature and of the forest itself. The current pace of our lives is often frenetic, and it is with profit that we would rediscover, on the occasion of this forestry project, the sense of long time and of transmission between human generations.

What will happen once the required area has been chosen and marked out, and the experiment begins? First of all, the pioneer trees, pines and birches, will die a natural death, enriching the soil and encouraging a diversity of fungi and insects. Then, without any planting, we will see the appearance of the post-pioneer trees, ash, lime and maple, which will build up the forest before ageing and disappearing in their turn; it is then that it will be appropriate to introduce those large animals that have not managed to arrive on their own, bears and bison, which will take advantage of the clearings and the first windfalls. Finally, oaks and beeches will take their place, and the primary forest will continue to grow in height and enrich in plants and animals.

During this long period when the forest will evolve freely and naturally, all plant removal and poaching must be prohibited, yet Europe’s primeval forest must remain wide open to visitors. Reconciling these two divergent imperatives, without them becoming contradictory, requires the collaboration of a wide range of skills.

The current aim is to ensure that our project is no longer just a national one, but that for reasons of stability and security, it becomes a major European project, integrated as such on the specific issue of the need to revive large primary forests, with existing schemes and measures or those being developed by Europe, such as the Green Deal launched by Mrs Ursula von der Leyen.

© Jessica Buczek
© Jessica Buczek
© Jessica Buczek

Cover photo: In the heart of natural forests, every death gives way to a multitude of new lives. Trunks and branches are quickly colonised by a wide variety of plants, insects and fungi. Light floods back into the forest, providing opportunities for dormant seeds, while windfall provides food and shelter for young shoots. Jessica Buczek

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