Oil palm can help to sequester more carbon
According to researchers from the World Agroforestry Centre, oil-palm plantations can help climate-change mitigation by not only reducing greenhouse-gas emissions through use as a biofuel but also by sequestering a considerable amount of carbon
In the Philippines, the Biofuels Act of 2006 mandates a 2% biodiesel blend in diesel and a 10% bioethanol blend in gasoline. According to Maruyama and others, the Act has fuelled a rising interest in biofuels and how they can help mitigate climate change.
The African oil palm (Elaeis guineensis), one of the oil-palm species planted in the Philippines, produces three to eight times more oil than other oil crops, including sunflower and coconut. The oil produced can be used as biofuel and in other non-edible products, like plastics and detergents.
Not only does the African oil palm provide greenhouse-gas savings compared to the use of fossil fuels it also sequesters carbon from the atmosphere, as has been described in the case of Indonesia by Tomich and others in 2002. A more recently published article, Carbon sequestration potential of oil palm in Bohol, Philippines, assessed the amount of carbon stored in the different parts of the African oil palm, one of the species planted in Bohol. The results of the study by Dr Florencia Pulhin, Dr Rodel Lasco and Joan Urquiola show that 9-year-old oil palm plantations in the Philippines can each sequester 6.1 tonnes of carbon per hectare per year.
The researchers assessed the carbon contents of six oil-palm plants from plantations aged two, five, six, seven, eight and nine years of the Philippine Agricultural Land Development and Mills Inc in Bohol. They divided the plants into six parts—trunk, fronds, leaves, fruits, flowers and roots—and measured the biomass of each to estimate how many tonnes of carbon could be sequestered by each plant and, by extension, each plantation.
When examining the biomass of the plants, the researchers found that older plants had more biomass than younger ones. Biomass is proportional to the amount of carbon stored, meaning that more biomass in the plant equals more stored carbon. This also means that older plants with higher biomass can fix, or sequester, more carbon. The results showed that the trunk with frond butts had the largest amount of carbon per plant, followed by the fronds.
Converting grasslands, which only sequester a tonne of carbon per hectare per year, into oil palm plantations would help in sequestering larger amounts of carbon.
According to Dr Pulhin and team, ‘… converting one million hectares of grasslands into oil-palm plantations will store about 55 million metric tonnes of carbon’.
However, this only applies when converting barren areas, not forests, because forests store more carbon than the expected amount from oil-palm plantations.
Read the journal article
This work is linked to the CGIAR Research Program on Forests, Trees and Agroforestry