Achieving sustainable increases in agricultural production in sub-Saharan Africa is both a regional and a worldwide concern. High human and animal population densities in some areas have surpassed

land-carrying capacities causing environmental degradation and undermining the long-term stability of these production systems. In attempts to meet the increasing food demands of larger populations,

farmers are cultivating more land permanently, grazing lands have diminished and many traditional farming practices that formerly allowed land to rejuvenate are disappearing.

This volume contains an executive summary of papers and the discussions on them as well as the reports of working groups and the recommendations of the Roundtable on Livestock Development strategies for Low Income Countries. In addition to the executive summary there is a Keynote paper and two other background papers, two papers on issues, constraints and opportunities for livestock development and five papers on options for increasing livestock's contribution from the major production systems.

Watershed management involves the integrated management of a multitude of resources such as crop land, pastures, forests and water to each of which a multitude of often conflicting interests relate. These interests arise from stakeholders inside as well as outside the watershed. The identification and negotiation of these interests therefore is an important element in watershed management.

This workshop was conducted to identify and prioritise areas of rumen ecology which are promising for their potential impact on improving nutrition status of tropical ruminants, to develop a rumen ecology research programme for ILRI based on relevance to developing countries and ILRI's comparative advantage vis-a-vis other institutions, to identify potential collaborators in advanced research institutes, and to define model(s) of collaboration.

In the Sahelian rangelands biomass production is constrained by soil moisture in the drier (100-250 mm) parts and by soil nutrients in the wetter parts. Similarly, for a given Sahelian range, nutrient deficiency would be more prominent in good than in poor rainfall years. To test this hypothesis, fertiliser trials were carried out at sites distributed along the bioclimatic gradient in the Gourma (Mali) over contrasting rainfall years between 1988 and 1992.

The integration of crops and livestock has often been cited as a model for agricultural development in semi-arid West Africa. Recent formulations treat the adoption of more intensive forms of manuring as a critical step in agricultural development. These analyses have been criticised for ignoring or underestimating the possible negative consequences of such management on rangeland and livestock productivity. This paper critically examines this debate. It is argued that the agronomic benefits of manuring depend largely on nutrient transfers from non-cropped grazing lands.

Paper explores the relationships between the following concepts under the conditions of Middle Eastern semi-arid ecosystems. Paper states that there are two apparent contradictions in the title of this paper. First, grazing by domestic livestock is often considered to be hostile to nature conservation, especially in semi-arid areas (the ongoing conflict between ranchers and environmentalists in western USA is just one contemporary example of this).

Results from this study show that the over-used but under-researched association between grazing and land degradation in the Kalahari has been oversimplified. In typical Kalahari conditions, the ecological changes that have been brought about by grazing cannot be linked with more fundamental changes in ecosystem function. Basic soil processes appear relatively unaffected by grazing pressure outside the sacrifice zone, and there is no evidence to suggest that the resilience of the system has been affected through soil degradation.