In this period of development, when the question of our new relationship with nature arises, does man run the risk of doing worse than better, if he falls in love with wanting to repair the damage he has already done?
In the temporary absence of man in the heart of cities, it is not because some of us have discovered or rediscovered the melodious song of birds, or even secretly observed a few deer or foxes, that this is the great return of the Wild. These few scouts were quick to clean up once human activities resumed. Today nature has indeed been greatly and lastingly changed, if not destroyed by human activities. Between agricultural overexploitation, soil sealing and urbanization, as much as 75% of the Earth’s surface has been degraded according to the latest United Nations Agriculture (FAO) Food and Agriculture Organization report on soil erosion. The crucial question then arises whether man should intervene or not to erase this imprint, unless it is already permanently indelible!
Restore, rehabilitate, replant, rewild?
In terms of ecological restoration of ecosystems, the vocabulary used seems as rich as the biodiversity it is supposed to revive. Ecological restoration in the strict sense therefore consists of the integral restoration of nature, including all its biodiversity, all interactions between living beings and their habitats, but also all the properties that result from this for autonomous functioning. A swamp is restored not only for the rare bird species it hosts, but also for its role as a regulator of the water cycle to protect against future periods of drought or flooding. It is then no more and no less than bringing nature back to the same landscape as a landscape frozen forever in an old postcard. Conversely, ecological rehabilitation is more modestly content with restarting some functions such as restoring the soil in the mountains or the banks of rivers to counter erosion, regardless of the diversity and natural character of the restored landscapes. Finally, as the name suggests, revegetation consists of simply regreening degraded spaces without regard to the origin of the planted species, their potential ecological role, or even attempting to mimic a pre-existing landscape of natural space. .
Conversely, rewilding or renaturing would consist of returning to nature the ability to evolve freely once the causes of degradation have been removed and the major players such as wild herbivores (European bison, tarpans, aurochs, etc.) and their super predators ( wolf, lynx, bear) moved. In France, however, there is no rewilding operation on the scale of the thousands of hectares that would be necessary for the success of this type of operation. Several large herbivores have indeed moved to viewing parks such as the European Bison Reserve of Margeride in Lozère, but in areas that are still far too small to allow a real return to the functioning of “natural” nature without the effect of neighborhood with nearby human activities or abandoned for a very long time. Certain invasive species thus threaten the biodiversity of Antarctica, while the floristic composition of certain European forests and meadows is still influenced by agricultural practices from antiquity or even the Neolithic. Rewilding on the scale of the European continent is therefore not for tomorrow!
Do it again, do with it or let nature take its course?
However, while many feedbacks of ecological restoration experiences have already been reported in the scientific literature, it will have been necessary to wait until the early 21st century before the power of computers allowed a more global view of the efficiency of these operations. by the achievement of statistical meta-analysis of several hundred cases around the world. Whatever the ecosystem considered, the results show that the restoration interventions indeed had significant beneficial outcomes compared to the initial degraded or altered stage. In short, the operations set up by man have often done better than leaving the site as it was. A certain degree of recovery is therefore quite possible given the state of scientific knowledge and the current technical and socio-economic resources.
On the other hand, and significantly, for the most part, these operations do not restore all the components and functions of nature that existed before its degradation. So we cannot “recreate” nature in an identical way, because life is dynamic and constantly evolving. The “restored” copies of the original will then always be imperfect, especially in a context where global changes no longer allow us to imagine a restoration under climatic conditions identical to those that led to the formation and conservation of the chosen historical reference. . This applies to the restoration of nature as well as to that of our cultural heritage: even if we still had the artists from then, it is unlikely that they will make the same works today as they used to!
If we don’t succeed in actively restoring the totality of pre-existing nature, shouldn’t we rather let it be? It is also known “Chase the natural, it comes back at a gallop”, nature does have global resilience. So there is no place on earth that has been definitively deprived of life, not even where man has been particularly determined to destroy it voluntarily or involuntarily, as, for example, in the exclusion zone of the site of the damaged Chernobyl nuclear power plant, which was built in the has become a true refuge of biodiversity over the decades.
‘Doing with’ or ‘making things happen’ thus leads to the emergence of ‘new natures’ whose composition and structure cannot be linked to old analogs that reassure us like our traditional rural landscapes. Hedges, meadows, pastures and forests are often the references in the field of active nature restoration in Europe. The interactions between species within new ecosystems are often unprecedented and it is therefore difficult, if not impossible, to predict their new trajectories in a changing world. There is therefore no reason to argue that with maturity they will achieve the same richness and heritage value as the historical references chosen in active restoration. It is therefore often a precautionary principle that leads to intervention. So we would accept more in terms of ecological restoration, an imperfect restoration of an old painting, than to convert it into a form of contemporary art…
Not recovering for nature, but by nature?
However, between intervening and letting go, there is a third way that would limit the environmental and economic costs of active restoration interventions while minimizing the uncertainties associated with free speech. It is then a question of acting thanks to “nature-based” solutions that are mainly aimed at controlling certain components or functions of ecosystems. Some fungi are already used to fix radio elements, plants of the legume family to restore soil fertility. Worms, ants and termites are also known for their ability to restore not only soil but also vegetation through their seed transport. Large herbivores are also essential for the restoration of herbaceous plant formations, beavers for the diversity of river ecosystems, etc. Thus, in the long term, the ecological transition should allow us to move from civil engineering to true ecological engineering, a variation on the natural contract. , dear to Michel Serre.
On the occasion of the Agir pour le vivant festival held in Arles (Bouches-du-Rhône) from 24 to 30 August 2020, in collaboration with the editions of Actes Sud, the editorial staff of
offers its readers forums, interviews and insights, as well as a selection of articles on the topic of biodiversity from our archives or our “Green Wire” section.
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