Study shows how land use is disrupting forest carbon sinks

Tropical forests contribute less to carbon dioxide uptake than boreal forests: scientists
Large land area with patches of forests and cleared areas
Aerial view of the Amazon Rainforest, near Manaus, the capital of the Brazilian state of Amazonas. CIAT/Neil Palmer

Related stories

Tropical deforestation is having a greater impact on the global carbon cycle than was previously realized, according to new research.

A study led by researchers at Sweden’s Lund University, published in Nature Ecology & Evolution journal posits that land use intensification in the tropics means that tropical forests are contributing much less to carbon dioxide uptake.

Measurements of anthropogenic land use and land cover changes (LULCC) led scientists to conclude that LULCC have had a greater impact on tropical forests than previously estimated, causing an increase and decrease of the contributions of boreal and tropical forests, respectively, to the terrestrial carbon sink.

“Climate change is affecting us all, and with this study we have increased our understanding of the impact of land use on the global carbon cycle,” said Torbern Tagesson, a physical geography researcher at Lund.

Because vegetation absorbs 30 percent of human carbon dioxide emissions it mitigates the effects of global warming and climate change, but due to deforestation, the terrestrial carbon sink, which takes in more carbon than it emits, is declining and the amount of carbon dioxide in the atmosphere is increasing.

Such heavily forested areas as the Amazon and Southeast Asia are contributing much less to carbon dioxide uptake than was previously realized due to LULCC, the report says.

The scientists determined biomass in tropical forests is decreasing by studying data from between 1992 and 2015 they gathered from a new satellite imaging system.

By combining the data gathered from tropical and boreal forests with dynamic vegetation models, they learned how much carbon dioxide is absorbed by different ecosystems around the world. Tropical and boreal forests contributed equally, and with the largest share of the mean global terrestrial carbon sink, they said.

“As we have verified our estimates with other satellite data, we can now say with certainty that boreal forests contribute more to carbon dioxide uptake and tropical forests contribute less,” Tagesson said. “Previous studies have not shown the same decline for tropical forests.”

The scientists gleaned greater insight into the impact of land use on the global carbon cycle and a better understanding of the processes that affect carbon dioxide uptake from vegetation, the report said.

“This knowledge is essential for us to be able to predict the effects of present and future climate change and therefore also highly relevant for climate change policy,” Tagesson said.

Copyright policy:
We want you to share Forests News content, which is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0). This means you are free to redistribute our material for non-commercial purposes. All we ask is that you give Forests News appropriate credit and link to the original Forests News content, indicate if changes were made, and distribute your contributions under the same Creative Commons license. You must notify Forests News if you repost, reprint or reuse our materials by contacting
Topic(s) :   Climate change