Understanding the impacts on land use through GHG-water-land-biodiversity nexus: The case of oil palm plantations in Thailand

Abstract

The promotion of biodiesel from palm oil for on-road transportation during the past decade has led to the expansion of oil palm plantations, including in Thailand. Hence, it is necessary to study the effects of land use for oil palm and the linkage between each impact for a holistic understanding. Besides, the consideration of various impact aspects in terms of a nexus is necessary for suggesting appropriate practices or zoning, because a single impact evaluation may not be comprehensive. Therefore, this study assessed the land use impacts from oil palm plantations in the five regions of Thailand. The land use impacts studied were greenhouse gas emissions, water scarcity, soil quality, and biodiversity. The assessment indicated the southern region to be the most suitable for further expansion of oil palm plantations, which is consistent with the government recommendation. However, if the expansion of oil palm in other regions is necessary, the central region is recommended because of available irrigation supply and better soil fertility compared to other regions. This study found that the land use impacts resulted from unsuitable management of oil palm plantations in the past. The increase of greenhouse gas emissions was mainly due to the excessive use of chemical fertilizers for soil quality improvement and water pumping from irrigation water consumption. Meanwhile, the deficiency of water availability led to the degradation of biodiversity and ecosystems. To decrease the land use impacts in the long run, suitable practice is important for sustainable oil palm plantations.