Less known than the great masses dedicated to the climate – such as the one that has just ended in Sharm el-Sheikh in Egypt – the COP15 devoted to the preservation of biodiversity opens on December 7 with the objective of protecting at least 30% of land and sea areas by 2030. Faced with the dramatic collapse in the number of species on the planet, this mission seems as important as reducing greenhouse gas emissions. However, it arouses less interest, as if the stakes were not understood. Nicolas Mouquet, researcher at the CNRS, Director of the Center for Synthesis and Analysis of Biodiversity in Montpellier, returns for L’Express to the reasons for this worrying discrepancy.
L’Express: For some ecologists, the scientific community on the climate got mobilized ten years earlier than that on biodiversity. Not only is it ahead of the curve, but it is unwittingly competing for attention on environmental issues. What do you think ?
If this competition exists, it is above all due to the space available in the press for themes linked to environmental crises (climate, biodiversity, etc.). Then there is above all a difference in the accessibility of the messages to be transmitted: with regard to climate change, the message can be summarized by a temperature increase of 1, 2 or 3°C depending on the scenarios. The reality of climate change is of course much more complex: some areas will warm up others will not, the changes will also affect other aspects of the climate such as rainfall, etc. However, despite the complexity of the issue, the problem was able to be simplified into a figure understandable to all. If we look at the biodiversity crisis, things become even more complex. We are talking about several million species impacted by exploitation, deforestation, global warming, etc. The consequences differ according to the ecosystems and the pressures exerted on them. In short, we find it difficult to communicate a figure that summarizes the situation to the general public. The International Union for the Conservation of Nature (IUCN) does a good job with the red list, which it updates every year and on which it communicates in an efficient and understandable way. The same goes for the WWF, for example, with its recent “living planet” report, which shows a 69% drop in wild vertebrate animal populations in less than fifty years. These are simple messages to understand, but here again, for the general public to feel concerned, it would have to impact us in our everyday lives. The climate is a subject of almost daily discussion among the French… Biodiversity, on the other hand, remains distant.
Perhaps we should communicate more about its positive effects? Coral reefs, for example, make tsunamis much less deadly. Drug research also benefits from healthy biodiversity.
The link between biodiversity and the functioning of ecosystems is no longer a debate. The diversity of life offers humanity shelter and food! It is also where most of the molecules that make up our pharmacopoeia come from. It is an integral part of our culture, contributes to our physical and mental well-being and is a source of inspiration for our artists, engineers, etc. On a larger scale, the researchers show that it participates in a form of environmental regulation by creating microclimates which will make it possible to attenuate the effects of climate change, for example by fertilizing the soil, or by protecting us from the effects of the rise of the sea level to use the example of the coral reefs that you mention. It also holds keys to our future; moreover, we now speak of “nature-based solutions” with regard to the mitigation of environmental crises.
“We can never bring back an extinct species”
What negative effects would we be exposed to if biodiversity deteriorated too much? Describing them would undoubtedly help the French and decision-makers to better understand the problem.
The answer is simple, if biodiversity deteriorates too much we run the risk of losing all the benefits that we have just mentioned. Moreover, we have a big uncertainty in the way in which the services which it renders to us will deteriorate. These can be reduced in proportion to the decrease in biodiversity, but there can also be what are called abrupt changes of state, i.e. thresholds of biodiversity loss beyond which essential ecological functions will no longer be fulfilled and entire ecosystems will collapse! And here, there is no way of knowing it before it is too late.
Finally, is the collapse of biodiversity even more worrying than the rate of reduction of our CO2 emissions?
Ranking is out of the question. Environmental crises are all concerning and interconnected. The only difference being that even if we manage to reduce our CO2 emissions and limit global warming, we will never be able to bring back an extinct species. We are in the process of accumulating an environmental debt, but only part of it can be repaid and the question is to know at what point the irrecoverable part of this debt will become unsustainable for the functioning of the ecosystems on which we depend for our survival! What to do to rectify things? In the immediate future, we must protect more natural spaces. The stated objective of protecting 30% of the planet by 2030 is a good idea, but this 30% must be chosen in such a way that the various components of biodiversity are protected. For now, the positioning of nature reserves has a strong historical component that does not necessarily correspond to the ecological reality. For example, in France, 30% of the mountain area is protected against 13% of the national territory; only 1.6% of the French maritime area benefits from strong protection status! In short, we see here the complexity of the problem.
Then, there is a huge amount of work to be done to communicate positively about biodiversity to the general public. We are disconnected from biodiversity, because we live less and less in direct contact with it. This disconnection does not allow us to understand the challenges of the current decline and to experience the first consequences. This implies, for example, bringing nature back into the city, talking about it from early childhood, putting children in direct contact with it as much as possible. We are talking about impregnation here. Let the idea of preserving biodiversity become as obvious as that of protecting the water we drink. It also seems necessary to drastically increase the resources we make available to scientists. We are still sorely lacking in data; the current state of biodiversity remains underestimated. For example, the IUCN has already assessed the status of 105,732 species. This may seem huge, but compared to the 10 million species that inhabit the earth, this only represents 0.01%! A drop in the ocean of biodiversity that we will have to protect.