The Impact of Droughts and Forest Fires on Tropical Lowland Rain Forest of East Kalimantan

Abstract

Lowland tropical rain forests have generally been regarded as ecosystems in which natural fire was excluded by fuel characteristics and the prevailing moist environment (Richards 1966; Mutch 1970; Mueller-Dombois 1981). However, recent findings demonstrate that climatic conditions since the late Pleistocene have favored the occurrence of natural and anthropogenic fires in the Amazon Basin and in East Kalimantan (Sanford et al. 1985; Saldarriaga and West 1986; Goldammer and Seibert 1989). It has also been demonstrated that the fuel characteristics, and the influence of drought on the microclimate and flammability of rain forest, may create conditions suitable for the occurrence and spread of long-return interval wildfires in today’s primary rain forests (Uhl and Kauffmann this Vol.). Modern human impact on tropical forest lands is rapidly increasing, causing overall degradation, and conversion of rain forest vegetation to pyrophytic life forms with increased flammability and fire frequency (Mueller-Dombois and Goldammer this Vol.; Goldammer 1991).