A new Moroccan study in the Maâmora forest shows that older cork oaks store far more carbon, up to 231 tons per hectare compared to 49 in young stands, making them key natural allies against climate change. Researchers from the National Forestry School of Engineers in Salé urge protecting old trees while restoring younger ones to keep Morocco's dry forests resilient and climate-smart. Older cork oaks in Morocco's Maâmora forest store the most carbon, according to a new Moroccan study. The research offers the first detailed look at how carbon accumulates across different tree ages in the Mediterranean's dry ecosystems. The study, led by researchers from the Soil, Water, and Biodiversity Department of the National Forestry School of Engineers in Salé, was published this week in the Journal of the Saudi Society of Agricultural Sciences. It examined how much carbon is stored above and below ground across six age groups of cork oak stands, ranging from under 10 years to more than 120 years old. Measuring carbon in Morocco's iconic forest To reach these findings, the team collected soil and plant samples from Canton B of Maâmora forest, which stretches over 70,000 hectares along Morocco's Atlantic coast. Using established forestry equations and laboratory analyses, they calculated carbon stored in four «reservoirs»: aboveground biomass (trees and shrubs), belowground biomass (roots), necromass (litter and deadwood), and soil (down to 40 cm deep). The results showed that older stands, especially those over 120 years old, contained up to 231 tons of carbon per hectare, compared to only 49 tons in young stands. On average, soil represented the largest carbon pool, accounting for over 60% of total storage. «Our findings show that older cork oaks continue to capture and store carbon long after they mature», the authors noted. «Preserving these stands is vital, as they act as long-term carbon sinks in Morocco's dryland ecosystems». A climate-smart future for Maâmora While old trees store the most carbon overall, the study found that younger stands absorb it more quickly. This means both age groups are essential: older forests act as stable carbon banks, while younger ones are dynamic carbon absorbers. With its vast expanse of cork oaks, many over a century old, Maâmora alone stores an estimated 9.9 million tons of carbon. Yet overexploitation, grazing, and drought are threatening its resilience, the study warns. The authors recommend a «climate-smart» forest strategy: protecting old-growth stands as permanent reserves while restoring younger areas to maintain diversity and carbon uptake. «Each hectare of mature cork oak holds more than four times the carbon of a young one», they conclude. «Safeguarding these forests is not only an ecological duty but a powerful natural tool against climate change».
