This is a Ph.D. dissertation. Why do farmers intensify their agricultural practices? The Iraqw'ar Da/aw area in the Mbulu Highlands of northern Tanzania has long been known for its intensive cultivation, and referred to as an "island" within a matrix of less intensive land use.
The conventional explanation for its characteristics has been high population densities resulting from the prevention of expansion by hostility from surrounding pastoral groups, leading to a siege-like situation.
Drawing on an intensive program of interviews, detailed field mapping and studies of aerial photographs, early traveler's accounts and landscape photographs, this study challenges that explanation. The study concludes that the process of agricultural intensification has largely been its own driving force, based on self-reinforcing processing of change, and not a consequence of land scarcity.
