The Preliminary Study on the Comparative Assessment of Carbon Stock Related to Changes in Land Use in Phuket and Phayao Provinces

Abstract

Recently, land use in Thailand has been significantly changed due to the dynamic from economic development. One of the consequence is the change of soil carbon stock. This study investigates the carbon stock change related to the change in land use in Phuket and Phayao due to the development of agriculture and tourism - two main economic sectors in Thailand from the years 2007 to 2009. Phuket is chosen as a representative of tourist provinces, while Phayao is chosen as a representative of agricultural provinces in Thailand. In order to determine land-use change in these two provinces, Geographic Information System (GIS) was employed, and to calculate the carbon stored in soil, Intergovernmental Panel on Climate Change (IPCC) 2006 Guidelines were applied. Land use in Phuket - a tourism destination was altered due to the tourism expansion. From 2007 to 2009, village and golf course areas grew by 48.1 km2 (45.2%) and 3.6 km2 (3.4%), respectively, while that of other urban (for example, factory and trading centers of agricultural product), other land (for example, mining and landfill), rubber, and evergreen forest areas dropped by 28.2 km2 (26.5%), 11.1 km2 (10.5%), 4.1 km2 (3.8%) and 3.4 km2 (3.2%), respectively. Because of the conversion from forest area (including evergreen forest, deciduous forest, and mangrove forest) and rubber plantation into settlements areas, the total carbon stock in Phuket felt by nearly 130,000 t C from 2007 to 2009. Differently, in Phayao, most of land-use change is due to the effect of agriculture. Between 2007 and 2009, the area of rubber plantation and other agricultural areas increased by approximately 50.5 km2 (27.8%) and 34.5 km2 (19.0%), respectively. While the area of corn plantation and deciduous forest declined by 46.66 km2 (25.7%) and 28.5 km2 (15.7%), respectively. The deforestation was caused by the expansion of other crops' plantation area, while the maize plantation area was converted mostly into rubber plantation and longan. The decline in the area of forest including evergreen forest and deciduous forest was the main reason for a reduction of more than 500,000 t C in soil carbon stock in Phayao. Even though there were different trends in the change of land use in two provinces, both of them have undergone a decrease in soil carbon stock - the important matter that can change to be greenhouse gas emissions in atmosphere due to that decrease. Therefore, it is necessary to establish appropriate policy for land use planning and management in Phuket and Phayao to reduce loss of soil carbon stock in these provinces.