The hidden carbon cost of converted peatlands

Now, an NTU-led study suggests that after tropical peatlands are converted into plantations for making paper, a large amount of ancient carbon stored in the peatlands leaks into the plantations’ drainage canals in a dissolved form.

This matters because carbon that eventually escapes through water canals is often overlooked when measuring the climate impact of peatland conversion.

Led by Nanyang Asst Prof Pierre Taillardat from NTU’s Asian School of the Environment, the study measured the concentration, types and age of carbon dissolved in the water of drainage canals serving a plantation in Sumatra, Indonesia.

Previously a peatland over 5,100 years old, the plantation now houses acacia trees for making paper products.

The researchers found that carbon leaked from the former peat soil into the plantation’s canals was, on average, about 470 years old, similar to other peatland-converted plantations in the region. The concentration of dissolved carbon in the plantation’s canals was also more than twice the average found in natural streams draining tropical peatlands.

Compared with the streams in natural peatlands, the plantation’s canals had lower levels of carbon as methane but across a larger area. While such a decrease suggests a short-term climate benefit, the study shows that converting natural peatlands into plantations reverses the land’s overall ability to accumulate and store large amounts of carbon over the long term.

---

The research is published in “Methane and carbon dioxide production and emission pathways in the belowground and draining water bodies of a tropical peatland plantation forest”, in Geophysical Research Letters (2025), DOI: 10.1029/2024GL112903.

The article appeared first in NTU's research & innovation magazine Pushing Frontiers (issue #26, May 2026).