Plants are the foundation of the ecosystem, yet it is difficult for us to name extinct species, and plants are more threatened than birds and as much as mammals. Nearly three species of plants disappear every year. An alarming rate that is not likely to slow down if our way of life does not change.
Part 1 : Endangered and extinct plants
•Let's start by asking : what is an extinct species?
In biology and ecology, an extinct species is a species considered to have no living representatives, both in nature and in captivity. We speak of extinction when a species or group has completely disappeared, thus reducing biodiversity. A study published in the journal Nature Ecology & Evolution reports that 571 plants have become extinct since 1750, which is twice as many as all the extinct birds, mammals and amphibians combined. The plants most affected by extinctions are trees, shrubs and other woody plants.
It is not so easy to prove that a plant species is extinct. Indeed, it can happen that some are rediscovered, as was the case of a Brazilian tree, the guarajuba, declared extinct in 1867 because it was overexploited for the quality of its wood. Finally, it was rediscovered in 2015. This anecdote is not a unique case; every year, scientists rediscover an average of 16 species of plants declared extinct. However, many others disappear before their existence is even discovered. It is estimated that a total of 20-30% of the plants on Earth have not yet been recorded.
•The extinction of species
In 1964, the IUCN (International Union for Conservation of Nature) established a Red List that lists the global conservation status of plant and animal species. In this list, each species or subspecies can be classified in one of the following nine categories:
Extinct (EX)
Extinct in the Wild (EW)
Critically Endangered (CR)
Endangered (EN)
Vulnerable (VU)
Near Threatened (NT)
Least Concern (LC)
Data Deficient (DD)
Not Evaluated (NE).
The species are classified based on a series of biological factors:
Population size
Rate of decline
Geographical range
Degree of settlement
Degree of fragmentation of distribution
A scientific review has shown that there are 8.7 million species of which 298,000 are plant species, and no less than 40% of these are threatened.
In particular the Perennial Panicaut (c.f Fig.1), this plant species is present in Europe including France. Unfortunately, it is becoming increasingly rare, and currently only exists in protected parks in Brittany. Indeed, the climatic conditions are no longer sufficient for its natural development, so that it risks disappearing for good within the next ten years.
The report in Nature Ecology and Evolution shows that almost 600 plant species have become extinct since the mid-18th century. This is 2.5 times faster than the disappearance of mammal, bird and amphibian species combined, with 217 species disappearing over the same period.
Since 1900, it is estimated that 3 species of plants disappear every year. For the year 2020, 3 plants have officially disappeared in the world:
Persoonia laxa (flowering plants of the Proteaceae family, Australia).
Leucadendron grandiflorum (flowering plants of the Proteaceae family, South Africa).
Ochrosia kilaueaensis (flowering plant of the Apocynaceae family, Hawaii).
The trees were also affected with the disappearance of the : Banara wilsonii, Euchorium cubense, Faramea chiapensis, Hesperelaea palmeri, Monteverdia lineata, Roystonea stellata.
Some of the plants classified as "extinct" are "functionally extinct", they have disappeared in the wild, but are still present in botanical gardens.
•The most affected areas
The extinction of plant species mainly concerns islands and tropical regions, which have a very rich biodiversity (islands represent 5% of the world's land mass and are home to 17% of the world's bird and plant species) but are also very vulnerable: the majority of species extinctions occur on islands. One of the major causes of extinctions on islands is due to the introduction of invasive species.
Hawaii is the most isolated archipelago in the world, which has allowed the development of a unique flora and fauna, with more than 90% endemic species, including 2,500 plant species. The archipelago also has the highest rate of extinction, with 79 extinct species out of 501 listed as endangered. The Cape Provinces in South Africa have 37 extinctions. Australia, Brazil, India and Madagascar are also among the most affected regions (c.f. Fig 2. ).
•Agricultural plants
These extinctions also affect agricultural plants, and according to estimates by the Food and Agriculture Organization of the United Nations (FAO), 75% of the diversity of cultivated plants has disappeared in a century. Since the birth of agriculture, no less than ten thousand plants have been cultivated; today, only 150 species of plants feed the planet. We can take tomatoes as an example, only 7 species have survived compared to about thirty in 1900. These are the consequences of an agricultural model that selects varieties that are more robust to climatic hazards, more aesthetically standardized and faster growing.
The evolution of cultivated diversity of soft wheat in France has radically decreased from 1912 to 2006 (c.f Fig 3. ). According to two indicators. On the left: number of varieties cultivated on a national scale. Right: Ht* index, the overall genetic diversity. It can be seen that despite a significant increase in the number of varieties cultivated, the overall genetic diversity of this crop has halved in a century.
•The extinction of plants in France
In metropolitan France, no less than 6070 species of native plants have been recorded, and 742 species are at risk of extinction (it's 15%). However, not all species have the same degree of threat, 9% are severely threatened and 22 species have already disappeared (c.f. Fig 4). Of these threatened species, 32% are ferns and 15% are flowers, Cry violet (Viola cryana) is one of the species considered as extinct at the world level. It was an endemic species of the Yonne department in France. The gum carline (Carlina gummifera) is considered to be a regionally extinct species.
A species is considered endemic when it is present exclusively in a defined geographical area.
The DROM-COM are very affected. A report published by the French Committee of the International Union for Conservation of Nature (IUCN) and the National Museum of Natural History (MNHN) shows that 15% of the 1,706 species of native vascular flora are threatened in Guadeloupe. 5 species have already disappeared and 110 are threatened, among them the orchid Anathallis mazei and the Ti-branda (Polygala planellasi),both endemic to the archipelago and classified as "critically endangered".
The plant of Reunion Island includes 237 endemic plant species out of the 905 plant species present on the archipelago, yet they constitute a unique heritage. Of the 905 plant species, no less than 49 species, 5.4%, have unfortunately disappeared from the island and 30% are threatened.
Part 2 : The causes of these extinction
The extinction of plant species is mainly linked to human activity. Indeed, human activities account for nearly 80% of plant extinction and have increased the extinction rate by a factor of 500. But there are other types of pressure, sometimes natural, such as the evolution of the coastline (c.f. Fig. 5 ), modified by the erosion of the border between the maritime and continental domains.
•The 4 major environmental threats
1 - Climate change
Frequent periods of drought (see our article on drought) are playing a role in the disappearance of many plant species. These droughts are linked to the increase in temperature, variable precipitation, and the intensification of heat waves and fires. As a result, plants are no longer able to adapt and die.
A report published in the journal Science states that climate change is causing the disappearance of birds and mammals, and a change in certain habitats, which reduces the ability of plants to adapt to climate change, so plant species have to move in search of more suitable weather conditions (see Fig. 6), but unfortunately some species are dependent on animals: barbane seeds have tiny hooks that cling to the fur of mammals; other species move via the digestive tract of animals.
For the islands mentioned above, one of the major causes of their vulnerability is climate change, which is causing a general rise in sea level and leading to the disappearance of islands.
Atmospheric pollution, linked to the human lifestyle (pesticides, air, sea and road traffic, energy production) also causes damage to plants. 90% of yield losses are due to air pollution. For example, pollutant gases disturb trees: their branches are deformed and leaves turn yellow. Pollutants such as diesel particles clog the pores of the leaves, making it difficult for the plant to breathe, which in turn disrupts photosynthesis. Acid rain, when a rain cloud meets a pollution cloud, is caused by air pollution. This rain will burn the leaves and make the soil less fertile.
Tourism is responsible for 8% of global greenhouse gas emissions, i.e. 3.9 billion tonnes of CO2 each year. It is one of the fastest growing sectors in the world and represents 10.2% of global GDP. With one in ten jobs, it is also one of the largest providers of employment in the world. According to the UNWTO, 95% of the world's tourists are concentrated in less than 5% of the land
2 – L'agriculture ;
In general, with the growing population, more and more virgin land has been transformed into agricultural land to meet human food needs. In addition, certain agricultural practices are proving to be harmful to biodiversity, such as overgrazing which degrades the soil or the abusive use of herbicides, so that the species that accompany harvests (the messicoles) are affected. Sometimes referred to as weeds, messicolous plants are an important resource for pollinators. Their populations are collapsing, with 18 of the 102 species on the national list threatened with extinction in France. Some of them are protected, such as the field tulip, the Savoy tulip or the pubescent larkspur. 7 are unfortunately already extinct, such as the harvest dill and the flax weed.
Soil pollution is also partly linked to agriculture. According to the European Commission's scientific service, 75% of the world's soil is now degraded. Erosion, chemical pollution, salinisation or the artificialisation of land with the expansion of cities and roads have visible consequences for plant species. (c.f. Fig. 7 ) When plants grow in polluted soil, yields are negatively affected in terms of quantity and quality. Many plants are unable to grow in contaminated soil due to changes in pH, reduced organic matter, decreased carbon reserves, and lack of water.
3 - Invasive species
What is an invasive plant? (c.f. Fig. 8 ) It is an exotic species, imported either involuntarily (for example when seeds of exotic species contaminate imported goods), or voluntarily for its ornamental value or economic interest (this is the case of many cultivated plants such as tomatoes, potatoes and corn, which, through their proliferation, transform and degrade natural environments more or less irreversibly). In France, the creeping primrose (Ludwigia peploides) is an invasive species. It was introduced around 1820 in the Montpellier plant garden for its decorative qualities. The invasion of the French territory started on the banks of the Lez - a seacoast river flowing in the Hérault department.
Although no species extinctions have been attributed to invasive alien species in Europe to date, there is a significant threat to local biological diversity, as well as to genetic diversity due to the potential for hybridisation between local and closely related alien species.
Climate change has an impact on the proliferation of invasive species, as they are particularly fond of heat, so we invite you to watch the video of the Ministry of Ecology and Energy on this subject!
Example of invasive plants in France:
Mugwort Ambrosia (Ambrosia artemisiifolia) or trifid ragweed (Ambrosia trifida) are highly invasive species 4% of French agricultural land is infested.
Japanese Hops (Humulus scandens). It is a rampant vine that spreads along riverbanks and greatly reduces biodiversity and modifies the structure of the ecosystem.
Giant Hogweed (Heracleum mantegazzianum) is an invasive plant that is most prevalent along roadsides and rivers.
4 - Urbanisation
Urbanisation contributes to 81% of the extinction of plant species, compared to 20% for natural causes (fires, etc.).
Indeed, the exponential growth of urbanisation is drastically reducing natural areas. For example, wetlands are increasingly shrinking and some species, such as the panicaut viviparous mentioned above, are disappearing. North America has the highest proportion of city dwellers: 83% (c.f. Fig. 9)
Globally, since 2010, the number of city dwellers has surpassed the number of people living in rural areas. By 2022, an estimated 57% of the world's population will be living in cities, a figure that could rise to 68% by 2050.
A wetland or wet region is where water is the main factor controlling the natural environment and associated plant and animal life. It occurs where the water table comes close to the surface or outcrops, or where shallow water covers the land.
Over-tourism also contributes to the intensive urbanisation of the territories:
The coastlines are affected by concretisation; Spain, one of the countries most affected by this phenomenon, has a rate of concretisation that exceeds 90% in some places.
Natural resources are consumed intensively; tourism increases the need for energy, food and water.
Waste is multiplying and polluting nature; in the Mediterranean, no less than 52% of rubbish is linked to beach tourism, according to the WWF.
Biodiversity is threatened (animal trafficking, disturbance of species, destruction of vegetation); Of the nearly 48,000 plant and animal species on the IUCN Red List of Threatened Species, 1,761 are threatened by tourism developments.
For example, Iceland had a large increase in tourism between 2010 (500,000 tourists) and 2017 (2 million tourists), which had serious consequences on the vegetation, which is why the Reykjadalur valley has temporarily closed in 2019. This phenomenon is amplified by social networks and the media, which popularise little-known places, resulting in large tourist flows.
PART 3 : Change the trend
MEPs strongly supported the EU's 2030 Biodiversity Strategy: to bring nature back into our lives, to ensure that by 2050 the world's ecosystems are restored, resilient and adequately protected.
Thus they commit to protecting at least 30% of the EU's marine and terrestrial areas (forests, wetlands, peatlands, grasslands and coastal ecosystems), and 10% of the EU's oceans and land, including all remaining primary and old-growth forests and other carbon-rich ecosystems, should be left essentially intact.
•Protected areas
All over the world we find protected areas, which contribute to the fight against the disappearance of many plant species. Their development is fundamental to the preservation of biodiversity. Today, there are 202,467 protected areas in the world, 14.7% of the world's land area (study by the IUCN and UNEP World Conservation Monitoring Centre).
The total surface of protected areas in France and its overseas territories is 33%. Among these protected areas there are :
-1756 Natura 2000 sites. The Natura 2000 network brings together natural or semi-natural sites in the European Union that are of great heritage value because of the exceptional flora and fauna they contain.
-355 nature reserves. A nature reserve is a type of area that is protected, more or less completely, by regulations and various physical and monitoring procedures and means: voluntarily, i.e. on the initiative of its owner, or as a result of a measure imposed by a state or community.
-58 regional nature parks.
-11 national parks. A national park is a portion of territory in which the fauna, flora and the natural environment in general are protected from human activities. The national parks represent almost 9.5% of the French territory, in 2019 the last national park was created, it is the first national park of temperate forests of plain in France, it covers about sixty communes on more than 56 000 hectares.
-8 marine nature parks.
-Prefectoral protection orders. Their aim is to combat the destruction, alteration or degradation of biodiversity. There are three categories:
biotope protection orders which preserve environments (natural or artificial) necessary for the survival of protected animal or plant species.
Protection orders for sites of geological interest.
Natural habitat protection orders, which aim to protect a natural habitat
•The different actions
Some plant species benefit from management, protection and even conservation measures with the development of seed banks. These are places where seeds are stored, in the short term, for agriculture, or in the long term, for preservation. The largest seed bank is located on the Norwegian island of Spitsbergen in the Svalbard archipelago. The Svalbard Global Seed Vault, also known as the "Plant Noah's Ark", was built in 2008 and houses about 980,000 plant seeds. (c.f Fig 12. )
In France, there are national botanical conservatories (CBN), including the one in Bailleul. These conservatories are approved by the Ministry of Ecological Transition and Solidarity, and carry out missions of knowledge, conservation, advice to public authorities, and public awareness for wild flora, vegetation and natural habitats.
Adopted in 2017, the national strategy on invasive exotic species is designed to protect marine, freshwater and terrestrial ecosystems, as well as the animal and plant species they host, from the risks and effects associated with biological invasions. The law n° 2016-1087 of 8 August 2016 for the reconquest of biodiversity, nature and landscapes introduced a section in the Environment Code on the control and management of the introduction and spread of certain animal and plant species.
Article L 411-5 bans the introduction into the natural environment of animal and plant species listed by decree.
Article L 411-6 bans the introduction into the national territory, possession, transport, peddling, use, exchange, offering for sale, sale or purchase of any living specimen of these species. However, there are exemptions for certain structures and reasons of general interest.
The decrees specify the lists of regulated species in metropolitan France and in each of the overseas territories.
Article R. 427-6 stipulates the classification of certain animals as nuisances with specific hunting conditions, particularly with regard to their impact on fauna and flora. In this regard, the order of 2 September 2016 on the control by hunting of populations of certain non-native species allows the destruction of invasive exotic species such as the coypu Myocastor coypus, the muskrat Ondatra zibethicus, the Canada goose Branta canadensis, etc.
The regulation on freshwater fishing (L.432-10) also limits the introduction of exogenous species in rivers and water bodies.
Tourism can also be done in a more sustainable and environmentally friendly way.
One of the solutions being considered to reduce the impact of travel on the climate is carbon offsetting. Some airlines are offering their passengers the chance to pay a tax to offset their CO2 emissions by financing projects in the field of renewable energy, energy efficiency or reforestation. The European Union is also considering a tax on fuel to reduce CO2 emissions. Since 1944, aircraft fuel has been exempt from taxes under the Chicago Convention in order to encourage the development of international routes. Today, several environmental groups are calling for fuel taxation to limit the impact of air traffic on the climate.
To go even further, we can reduce the harm at the source, by changing the way we travel and therefore limiting our air travel.
This is part of sustainable tourism, a tourism that respects, preserves and enhances the heritage resources of a territory by minimising the negative impacts it could generate.
In 2009, more than 70% of French travellers were aware of the concept of sustainable tourism and said they were ready to put it into practice. However, only 4% acknowledged having already purchased sustainable tourism products or services.
A good news is that French trains experienced record ridership in the summer of 2022, with a 10% increase in mainline usage compared to 2019 (pre-pandemic).
Creation of official eco-labels: For tourist accommodation, For visitor sites (monument, garden, zoo, museum, theme park...) At international level, there are more than 200 green labels and certifications in the tourism sector.
•And to go further ...
Research in the service of plants
Farm3 actively contributes to research for the conservation of vulnerable plants, in particular through the creation of ultra-plants more resistant to climate change thanks to acclimatisation, set up by our scientific teams, in our climate-controlled culture chambers, the FarmCubes.
We have promising first results on drought acclimatisation in trees (downloadable here).
Or more recently, by joining the Heritage Incubator. The objective is to communicate the importance of and find innovative solutions for plant conservation and to raise public awareness of environmental issues. This is why we are currently undertaking a collaborative project with the CMN (Centre des Monuments Nationaux) to work on ancient plant species, in order to recreate period gardens in French monuments.
•what can you do to protect plant biodiversity?
Leave the car to make a short trip
Choose local and seasonal fruit and vegetables
Sorting waste
Limit the use of plant protection products. Pesticides, insecticides, fertilisers and weed killers are the worst enemies of biodiversity. There are alternatives (thermal weeding, hoeing, use of insects for biological control, mulching). Mulching keeps the beds moist (mulch of bark, shavings, cocoa shells, etc.), which limits the appearance of spontaneous weeds and protects from the cold.
Leaving a corner of the garden uncultivated; much richer in plant species than a simple lawn.
Favour vegetal fences; rather than fences, walls or garden panels. These hedges promote biodiversity on several levels:
-They facilitate the infiltration and filtration of rainwater.
-They create continuity between animal and plant species and constitute a privileged habitat for many of them, such as birds.
Favour the train over the plane for trips that permit it.
Install insect hotels and participate in the reintegration of pollinators.
Taking care of insects; Over 70% of the food we eat depends on pollination. To facilitate the work of pollinating insects, you can plant in your garden or on your balcony a flower meadow (a mixture of perennial flowers) that does not require maintenance (there are ready-made seed packs for pollinators).
Conclusion
