Unlike a truck and SUV jam, a logging raft in the Mackenzie River Delta in Nunavut, Canada, stores carbon.
Covering about 51 square kilometers (about 20 square miles), it is the largest known fallow area on Earth, consisting of trees that fell from the surrounding forest and floated to the surface of downstream waters and were deposited in the delta. for centuries.
These forests collectively contain about 3.4 million tons (3.1 million metric tons) of carbon, a large but poorly understood carbon pool, according to a new study by researchers from the US and UK.
“To put it in perspective, we can say that this is about 2.5 million tons of car emissions per year. That’s a lot of carbon,” said Alicia Cendrowski, a research engineer at Colorado State University in the US who led the study.
Despite decades of data on how trees move around the Arctic, we don’t really know how much timber or how much carbon it contains that underlies the region’s crises.
“There’s a lot of work done on carbon fluxes from water and sediment, but until recently we didn’t pay attention to wood,” said Virginia Ruiz Villanueva, a geomorphologist at the University of Lausanne who was not involved in the study. It is important to study this wood not only in relation to the carbon cycle, but also to understand how natural river systems work in general and how rivers move and disperse wood.
Wood lasts a long time in the Arctic, where low temperatures and low humidity can help preserve trees for centuries or even thousands of years after they fall.
The Mackenzie River is full of trees of all ages, especially in the delta, which is the third largest river in the world by area. For the new study, the researchers examined nearly 13,000 square kilometers of the delta, the most ambitious mapping effort ever.
This included three weeks in the field, where researchers measured driftwood, mapped blocks, and took samples to determine the age of individual records with radiocarbon dating.
They also used satellite imagery to estimate the total area, which is about 400,000 smaller woody sediments. This helped them calculate the amount of wood inside the borehole and therefore the amount of carbon it was likely to store. The largest single stockpile in the stalemate is the size of about 20 American football fields and alone stores 7,385 tons (6,700 metric tons) of carbon, the researchers reported.
While their research shows that the total watershed stores 3.4 million tons of carbon, they point out that this is limited to the forests they can trace from the surface. Tree stumps are also buried in the delta’s soil, hidden under water, or covered by vegetation, so the researchers agree that their estimates are likely to be inaccurate. And they say whole pickles can contain twice as much carbon.
That’s huge even though its carbon-rich soil is still dwarfed by the Mackenzie River Delta, making it a carbon storage hotspot. According to previous research, the delta can store a total of about 34 billion metric tons of carbon.
Under normal conditions, the Arctic can store logs and carbon for long periods of time. About 40% of the records the researchers received began growing in 1955 or later, but most are older, with some dating back to 690 AD.
The researchers noted that the Arctic has at least a dozen river deltas larger than 500 square kilometers, which could create a network of carbon storage bottlenecks that would be prudent to study and protect.
The study was published in Geophysical Research Letters.
Source: Arabic RT