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Metadata only record In the Sahel region of West Africa, the traditional organization of the population and the grazing land avoided overexploitation of pastures. Since independence in the 1960s, grazing lands have been opened to all without specific guidance, and the vulnerability of the pastures to degradation has increased. Rotational grazing is postulated as a possible solution to provide higher pasture productivity, higher animal loads per unit land, and perhaps improved soil carbon storage. The objective of this study was to conduct a simulation-based assessment of the impact of rotational grazing management on pasture biomass production, grazing efficiency, animal grazing requirement satisfaction, and soil carbon storage in the Madiama Commune, Mali. The results showed that grazing intensity is the primary factor influencing the productivity of annual pastures and their capacity to provide for animal grazing requirements. Rotating the animals in paddocks is a positive practice for pasture protection that showed advantage as the grazing pressure increased. Increasing the size of the reserve biomass not available for grazing, which triggers the decision of taking the animals off the field, provided better pasture protection but reduced animal grazing requirements satisfaction. In terms of soil carbon storage, all management scenarios led to reduction of soil carbon at the end of the 50-year simulation periods, ranging between 4% and 5% of the initial storage. The differences in reduction as a function of grazing intensity were of no practical significance in these soils with very low organic matter content, mostly resistant to decomposition. SysCoor-2 (Farm/Enterprise)

Livestock management, as a means of determining the extent and value of nutrient flows in agricultural landscapes, is already well understood and exploited by small-scale farmers in Asia. This paper highlights the biological interfaces in smallholder agricultural systems where animals exert the greatest influence upon nutrient cycles, and suggests that these should form the focus of scientific effort to elucidate the key elements of the biological processes at work. Two case studies of intensive mixed farming systems are presented from the uplands of Java, Indonesia and the Mid-Hills of Nepal. These examples show how management practices have developed over centuries to enhance the contribution that livestock make to motivating and moderating nutrient flows on very small and continuously cultivated land holdings. The paper concludes by emphasising that there is an urgent need to understand the biological mechanisms that enable livestock to contribute to the sustainability of intensive smallholder agriculture.

Metadata only record In the Sahel of West Africa, the productivities of rangelands, croplands and livestock are inextricably linked. Cattle, sheep and goats graze rangelands and crop residues, and their manure/urine is used to fertilize crops. Rangelands provide important feeds during the manuring period, resulting in a net nutrient transfer from rangelands to croplands. This paper examines the sustainability of nutrient transfers in integrated rangeland/cropland systems of the Sahel by examining the impact of grazing on rangeland vegetation structure and floristic composition, the impact of livestock on nutrient balances of rangelands and croplands, and the role of livestock in offsetting nutrient deficits through manuring. Rangeland nutrient balances are in equilibrium (inputs = offtakes) whereas croplands lack the internal capacity to replenish nutrient offtakes in grain (as food) and crop residues (as feed). Although soil nutrient mining is of general concern for the Sahel, local management practices of some farmers (e.g. corralling animals overnight on fields between cropping seasons, use of fertilizers) offset cropland nutrient deficits. The number of additional livestock, and their feed requirements needed to supply sufficient manure to offset cropland nutrient deficits, depend on rangeland and cropland productivity, livestock production goals, and management strategies of farmers. Livestock must be managed so they do not deplete the nutrient supply of rangelands in order to increase the manure supply for improving cropland productivity. Sustained rangeland productivity in the Sahel will depend largely on producing alternative feeds derived mostly from croplands. Land use and tenure policies that inhibit livestock mobility and, therefore, farmers' access to the manure of pastoralists herds, will greatly undermine the resilience of Sahelian rangelands, and increase the need for other external nutrient inputs such as fertilizers to prevent declines in soil fertility and crop yields. (CAB Abstract)

A model of the dryland farming system in the eastern wheatbelt of Western Australia is briefly described. The model, named MUDAS, explicitly accounts for climatic risk and dryland farm management responses to such risk. Results from this model are compared with those from a model based on expected values and which therefore excludes climatic risk. The performances of the models are compared assuming two price scenarios. Results from the models show that climatic risk and its associated farm management responses lead to decisions often different from those generated by sole consideration of expected values. Levels of activities selected, in the model based on expected values, are often substantially different from those generated in MUDAS. However, the expected value model that ignores climatic risk and tactical responses to such risks still correctly identifies the desirable direction of strategic response to a change in price regime. Tactical decision-making, in response to climatic risk, is shown importantly to contribute to farm profit and to influence production decisions including the mix of enterprises. Profitable tactical decision-making in response to climatic risk causes wide variation across seasons in crop and pasture areas and crop and livestock management, and overall greatly modifies the farm management decisions that might otherwise be based on expected values. Results from MUDAS show that rigid adherence to rotations is not the most profitable managerial response to climatic risk. Instead managerial flexibility causing marked changes in crop and pasture areas across seasons is more profitable. The value of tactical decision-making and managerial flexibility illustrated in the MUDAS results points to a potentially profitable area of research and extension, this being the development of information or innovations that facilitates tactical decision-making.

The ‘Mouton de Case’ is a small-scale stall-fed system of sheep fattening current in West Africa. Most fattened animals are males, kept for slaughter at the annual Moslem Feast of the Sacrifice (tabaski). More than 25% of total annual offtake in local sheep flocks occurs in relation to this feast. In two local agropastoral sub-systems more farmers kept stall-fed sheep in an irrigated rice sub-system (39%) than in a rainfed millet sub-system (24%). Farmers in both systems fed approximately two animals. Supplementary feed is mainly cut grass and tree leaves and some agricultural by-products. Average daily gains of Mouton de Case were, at 117 g, almost twice those of extensively reared animals (60 g) of the same type.