Overview
- Published March 19 in Science, the Lund–Stanford analysis finds primary forests hold about 72% more carbon per area than managed forests when harvested wood products are counted, or 83% more excluding them.
- Soil is the main driver of the gap, with old‑growth soils alone storing as much carbon as managed forests hold across trees, dead wood, and soils combined.
- The storage difference is 2.7 to 8 times larger than official estimates, implying nearly 8 billion tonnes of CO2 could be kept out of the atmosphere if managed stands matched primary‑forest levels.
- Researchers mapped Sweden’s most natural lowland remnants, sampled more than 200 plots and about 220 soil pits to one meter, and integrated decades of national forest and soil inventories.
- The findings intensify scrutiny of Sweden’s old‑growth definitions under EU rules and of forest‑bioenergy climate models, as authors launch follow‑up studies on microbial and management drivers of soil carbon loss.