Agriculture, which dominates most of the African economies, has been the main focus of national development plans of most independent African countries for over two decades. Land policies and reforms of various kinds have been instituted and implemented with the aim of radically improving the performance of the agricultural sector. However, success has been mixed. In most countries, traditional practices and low productivity have persisted despite major reforms and large investments. Where agricultural innovations have been introduced, shortterm successes have often been followed by long-term problems.

The most frequently occurring of such problems is environmental degradation. In practice, many agricultural programmes tend to place a strong emphasis on quantitative increase in production and to be less concerned with qualitative aspects such as resource management and conservation. As a result, the environmental implications of, for example, changes in land use are often overlooked until serious physical deterioration has occurred.

In most parts of Africa there are many examples of environmental deterioration resulting directly or indirectly from changes in land use. This paper highlights some of these environmental implications of land-use changes. It examines the particular case of Tanzania, where a major nationwide resettlement programme was recently undertaken with the aim of transforming agriculture, improving productivity, and raising the standard of living of the people, the majority of whom reside in rural areas.