Biofuels as renewable energy sources, are considered as an option to meet the growing global energy needs, while mitigating climate change. However, determining whether biofuels could offer carbon savings without compromising food security has long been controversial. The major debate centers on that land use change (LUC) induced by biofuel production could lead to GHG emissions, which potentially increases biofuel’s carbon intensity. Among the sources of LUC-related emissions, the contribution from carbon-rich peatland converted to agricultural plantations in Southeast Asia remains uncertain. A recent study, by the Innovation Team for Ocean-Land-Atmosphere Interaction and Global Effect at the Southern Marine Science and Engineering Guandong Laboratory (Zhuhai), took a deep dive and looked into this matter.

By making use of emerging evidence available from field observations and remotely sensed land use data, the team analyzed LUC in Malaysia and Indonesia, and modeled its impacts on the GHG emissions of soy biodiesel produced in the U.S. A combination of economic model and emission models were used for global LUC and emissions estimation. The results show that palm plantations have more than doubled over 2001-2016, and the area of palm-on-peatlands has expanded 3.7 times (Figure 1). The peatland loss contributes 0.7-5.1 g CO2e MJ-1 to biodiesel emissions, about 9-48% of total LUC-related emissions. This study reduces discrepancies among model stimulations used by different agencies (Figure 1), and provides new insights into the estimation of LUC impacts on biofuels’ carbon intensity.

This study is now available online at Environmental Science & Technology (Impact Factor: 11.3), entitled “Peatland loss in Southeast Asia contributing to U.S. biofuel’s greenhouse gas emissions”. Professor Zhangcai Qin is the corresponding author, and Ph.D. student Yakun Zhu at Sun Yat-sen University is the first author. This study was supported by research funding via the National Natural Science Foundation of China, the Guangdong Provincial Department of Science and Technology, and the Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai).

Figure 1. Palm expansion and peatland loss in Southeast Asia.

Paper link: https://doi.org/10.1021/acs.est.2c01561