Structure diversity in three forest types of north-eastern Thailand (Sakaerat Reserve, Pak Tong Chai)

Abstract

The aim of the present study is to provide a basic knowledge in view of a better understanding of the global structure of threetropical forests at the Sakaerat Environmental Research Station (Pak Tong Chai district, Northeastern Thailand): a drydipterocarp forest (DDF), a dry evergreen forest (DEF) and an intermediate stage (DDFwf), characterized by the absence offire since 29 years in a pyro-climax. These forest ecosystems were contrasted by the composition and floristic structure, thebasal area and the tree density. The species richness increases with the passage from the DDF, the most open environment, to the DDFwf, the most densely wooded. By these tree density and basal area, the DDF (602 trees/ha at DBH ³ 5 cm, 14.2 m2/ha) and the DEF (992 trees/ha at DBH ³ 5 cm, 29.0 m2/ha) studied belong to the typical tropical ecosytems of southeast Asia. The man-made fires and anarchic forest exploitations are a danger for the stability of these different ecosystems.

Keywords

• Thailand
• Dipterocarpaceae
• forest inventory
• forest structure
• fire