Northern Australia: The Arenas of Life and Ecosystems on Half a Continent provides a geographical study of the interplay of environmental challenge and human endeavor in the vast arena of Northern Australia. This book is organized into three parts. Part A presents the contextual setting for Parts B and C. It includes a historical geographer's perspective on the ecological impact of 200 years of European settlement; a description of the use of satellite imagery; and discussion of some of the interactions among natural subsystems as they impinge on human activities (especially in the extensive rangelands). Part B discusses some of the human ecosystems which extend over a very large geographical territory. In these ecosystems the human population is small in terms of absolute number and relative to the population of other living things. These include the tropical marine ecosystems and their growing utilization for mariculture; and rangeland ecosytems dominated by cattle and the overlapping semi-arid grasslands. Part C discusses intensive ecosystems, where the human population is dominant in number.