Congo Basin’s Peatlands are More Than 42,000 Years Old, New Study Reveals
The Congo central basin contains the most extensive tropical peat bog complex, extending over 16.7 million hectares. Until now, the radio dating of ancient peat bog has been limited to 14 samples with poor coverage, and has suggested that the peat initiated during the Holocene. New research indicates that the peat initiated in the Congo central basin in several places in the Upper Pleistocene. The oldest date determined by the authors is 42,300 years earlier, which makes one of the oldest tropical peat bogs in the world, and twice older as before.
Swamp Forest in the Democratic Republic of Congo. Image credit: Greta Dargie.
The Congo central basin rides the equator, containing 360,000 km2 of a wetland shared between the Republic of Congo and the Democratic Republic of Congo.
Of this area of wetlands, around 167,600 km2 The marsh forest underpins the basket by peat deposits, with a middle thickness of 1.7 m.
These peat bogs are among the ecosystems richest in carbon on earth, storing an average of 1712 mg c ha ha−1With a total of 29 pg C−1 Stored in peat.
However, research on the establishment and development of this large carbon stock, including the dynamics of initiation and expansion of peat across the basin, is in its infancy.
“These peat marshes forests are a world carbon store, holding the equivalent of three years of world fossil combustible emissions,” said the researcher at the University of Leeds, Greta Dargie.
“We now know that they are among the oldest tropical peat bogs on the planet.”
The study started with research teams that shake away from distant and inaccessible Congolese peat swamps, using hand equipment to collect peat samples at 6 m under the forest floor.
Back in the laboratory, tiny amounts of peat were dated using radiocarbon, to determine when the peat started to form in each sampled location.
Over a period of 10 years, the researchers collected and dated more than 50 hearts from the entire Congo central basin, of which they were able to build an image of the development of peat bogs over time.
It was not only the great age of peat bogs that surprised scientists.
“One of the most unexpected results that come from our new data is that some of the older peat bogs in the Congo Central Basin began to train during periods of the past when we think that the regional climate was much drier than today,” said professor of the University of Marien Ngouabi IFO suspense.
“Our previous working hypothesis was that the peat began to train in response to a more humid climate at the start of the Holocene era, about 12,000 years ago.”
“But we now know that the factors other than the climate had to make the soils sufficiently damp and full of water for the peat forms.”
“This raises questions about how the peat bog and the large quantity of carbon IT stores, will answer the 21st century climate change.”
The peat swamps of the Congo basin provide significant resources for local communities such as fish, bush meat and construction resources.
Their distance means that swamps are important refuges for species such as forest elephants, dwarf crocodiles, plain gorillas and bonobo chimpanzees.
Compared to many tropical regions, Congolese peat bogs have largely escaped threats such as deforestation and drainage, although the desire to improve local subsistence means and to extract resources such as wood and oil for export can potentially conflict with the objectives of biodiversity and carbon conservation.
“The great age of peat bogs leads their precious to their precious,” said Dr. Pauline Gulliver, a researcher at the University of Glasgow.
“There was peat here, quietly pulling carbon from the atmosphere and storing it safely for at least forty millennia.”
“Peat cannot be replaced on any time scale that has meaning for society.”
“Where the peat bogs were disturbed by the people of the planet, they released huge amounts of carbon in the atmosphere, exacerbating global warming.”
“Carbon in the peat bogs of the Congo basin requires meticulous treatment for the same thing to happen here.”
The results were published in the journal Environmental research letters.
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Greta C. Dargie and al. 2025. Truck of the initiation of peat through the Congo central basin. Approximately. Res. Let 20, 084080; DOI: 10.1088 / 1748-9326 / ADE905
