Wetlands are disappearing when they are essential to our survival

Indispensable allies in the fight against global warming, wetlands are highly threatened and degraded all over the world. The United Nations estimates that 35% of wetlands have disappeared since 1970 despite having many unknown benefits, such as disaster mitigation, carbon sequestration and human health.

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The Wetlands Convention (Where Ramsar Convention) has just updated its last report on the state of wet area in the world and on the importance of their backup. While all eyes are on the degradation of the Amazon forest or on the disappearance glaciers, the wet area are the ecosystems the most threatened on the planet: the marshes, bogs, wet meadows, lagoons, mangroves and other water points are currently disappearing at a rate 3 times faster than forests. 36% of species dependent on wet area are threatened globally. Yet little known, the role of wetlands is crucial in the functioning of the Terre : reservoir of biodiversity, but also disaster mitigation, human health, and carbon sink.

Threats: agriculture, livestock, pollution and climate change

Wetlands have a cumulative global area of ​​1.2 billion hectares; this results in a territory larger than that of Canada. But in just 50 years, they have already lost a third of their total surface.

The anarchic exploitation of land (in particular agriculture and livestock) is the first factor in the degradation of wet area, while the Convention on Wetlands insists that “ the future of sustainable food production depends on healthy wetlands and their wise use ”. L’agriculture is responsible for the disappearance of more than half of wetlands since 1970. Next come the overexploitation of farm animals, plants, pollution, invasive species, but also Forest explotation, as well as the hunting and fishing of species essential to the functioning of these zones. And the Convention’s predictions are rather bleak for the future: all these threats to land and biodiversity ” are expected to continue or worsen in many future scenarios, in response to indirect factors such as rapid human population growth, unsustainable production and consumption, and technological development related. »

Agriculture has been responsible for the disappearance of more than half of wetlands since 1970

Wetlands are also particularly affected by the consequences of climate change: rise in sea level, coral bleaching and upheaval of thehydrology. Among all the wetlands of the world, the wetlands arctic and mountain are more exposed to climatic risks. In areas weather rather dry, caused to suffer even more from the drought with the global warming, the water stress is becoming more and more important, drying up many wetlands essential to biodiversity and to the human population.

Another geographical area where the deterioration of wetlands is unquestionable, the Mediterranean region. Since 1992, the marine biodiversity of the Mediterranean has decreased by 52% and its biodiversitypure water by 28%. the debit of rivers in the Mediterranean basin decreased by 25 to 70% between 1960 and 2000, with repercussions on seasonal wetlands. Intensive agriculture consumes two thirds of the freshwater resources of the Mediterranean. With more than 42% of the Mediterranean population living on the coast, establishments, industry and tourism are degrading coastal wetlands and demand for water is increasing.

The little-known benefits of wetlands

The interest in safeguarding and restoring the planet’s wetlands is manifold and often totally unknown to farmers, breeders and more generally to local populations. The Convention estimates that 4 billion people (out of a global population of almost 8 billion) are directly dependent on wetlands for their survival. The economic value of wetlands for the services they provide to humanity is estimated at $ 47.4 trillion per year!

One of the goals of the United Nations is to restore 50% of peatlands destroyed by 2030.

Coastal wetlands, such as mangroves, sequester the carbon dioxide 55 times faster than tropical forests. The bogs, which cover only 3% of the world’s surface, sequester 30% of the carbone present underground. Peatlands and coastal blue carbon ecosystems (salt marshes, mangroves, seagrass beds, etc.) in good condition are very efficient carbon sinks, but if they are degraded, they become important sources of carbon. greenhouse gas.

One of the objectives of the United Nations is moreover to restore 50% of the destroyed peatlands by 2030. Mangroves, Coral reefs and the algae navies also act as barriers that mitigate the submersion ribs in case of storm and tsunami. On land, peat bogs, ponds, rivers and water points in general absorb excess water in the event of a flood and retain it in the event of drought. These ecosystems are part of what are called the Nature Based Solutions.

The good health of the population also depends on well-managed wetlands: “ Control of emerging zoonotic diseases depends on the preservation of intact and well-managed ecosystems and local biodiversity. Taking an ecosystem approach to wetlands can have health benefits for everyone. The degradation of ecosystems and the senseless trade in wildlife increase the risks of pandemics devastating and three quarters of new diseases are of zoonotic origin ”. What’s more, ” water-related diseases, such as diarrhea children, transported in unsanitary waters, are also favored by poor management of wetlands and kill millions of people every year ”.

In order to better publicize the importance of wetlands and encourage their protection and restoration all over the world, the United Nations General Assembly of August 30, 2021 decided to dedicate a World Day to these ecosystems. February 2 of each year will henceforth be “World Wetlands Day”.

Ramsar sites in France. © Ramsar France

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