Cattle, commons, and culture: The political ecology of environmental change on a Tanzanian rangeland

In this thesis I examine the social causes and consequences of ecological change on an East African rangeland. I conducted fieldwork on the Usangu Plains of Mbeya Region, southwestern Tanzania between November 1989 and February 1991. The thesis investigates how ecological change that had occurred on the Plains over the forty-year period 1950-1990 was linked to social processes taking place at both the micro- and macro-levels during this same time period. It also explores how ecological change is perceived and experienced by three different ethnic groups of livestock herders residing on the Plains, and how they have responded to it.;This thesis contributes to two main bodies of scholarly inquiry: to explanatory theories regarding the causes of land degradation, particularly rangeland degradation, in Africa; and to frameworks for understanding cultural constructions of nature and environmental change. I hypothesize that ecological change on the Usangu Plains between 1950 and 1990 was the result of the transformation of common property resources there from communal property to open access status. In the thesis I detail the historical processes by which this transformation came about. I also argue that ecological change on the Usangu Plains has been detrimental to some livestock herders, but not others; and has been perceived by some herders--but not others--as constituting environmental degradation. These differences vary in relation to ethnicity in particular, demonstrating that environmental degradation is to a large degree a cultural construction rather than a purely natural fact. Because different cultural constructions of nature shape peoples' resource use and management practices, they have different ecological consequences. Different cultural constructions of nature also have important implications for the politics of resource management. I explore these relationships in the thesis, with an emphasis on how they relate to the practice of natural resource management and conservation.