Transition in distribution of tree in connection with changes in their utilization of the tree-rice ecosystem in Northeast Thailand

摘要

Introduction: The tree rice ecosystem~Paddy field with many standing trees is a particular landscape in Laos and Northeast Thailand which was first called "産米林"by Takaya and Tomosugi (1972). Unlike paddy fields in other developed countries, this tree rice ecosystem contains diverse and abundant natural resources. Processing with satellite images by GIS, variation of tree density in paddy fields among regions has been obtained. Socio-economic situation collected through interview local residents and real observation at sites are basic knowledge to discuss about factors causing such variation. Through the investigation, we acknowledged that distribution of tree in paddy field has trend to change from in paddy floor to be on paddy levees. Since transition in density and distribution of tree may link directly to changes in land use practice, we hope our study can contribute as a basic data for further research in order to propose appropriate measures to conserve this resource-rich ecosystem and a sustainable agriculture in those countries.