This book presents the full text volume of the IUFRO (International Union of Forestry Research Organizations) Conference on Environmental Forest Science which was held in Kyoto, Japan on 19-23 October 1998. The conference was organized by IUFRO Division 8 Forest Environment and Kyoto University. Forests as environment for mankind as well as environment of forests per se are increasingly important in progress of current urbanization and regional development. The objective of this conference is to integrate many fields of related sciences to a new concept of environmental forest science, which will be developing and promising in the 21st Century. The book consists of sixty nine papers covering forests as environment from various aspects, forest ecosystems & biodiversity, forest hydrology, natural disasters (landslides and debris flows et al) in mountains and their reduction. The publication will be of value to foresters, ecologists, hydrologists, landslide engineers and policy makers related to environments.