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A simple ecological model underlies contemporary fire policy in many West African countries. The model holds that the timing (or seasonality) of annual savanna fires is a principal determinant of vegetation cover. The model's origin can be traced to the ideas held by influential colonial scientists who viewed anthropogenic fire as a prime force of regional environmental degradation. The main evidence in support of the model derives from the results of a series of long-term burning experiments carried out during last century. The experimental results have been repeatedly mapped onto fire policy often taking the form of a three-tiered model in which fire exclusion is considered the ultimate management objective, late dry-season fire is discouraged and early dry-season fire is allowed but only under specific, often state-controlled circumstances. This paper provides a critique of contemporary fire policy in the region and the fire ecology model on which it is based. Through an analysis of burn scars for the 2002–3 fire season generated from ETM+ imagery, the study documents the spatiotemporal pattern of burning for an area in southern Mali. It argues that current policy, which is informed by an a-spatial model, cannot adequately account for the critical pattern of burning that is characteristic of the region. A reinterpretation of the burning experiments is presented in light of four factors: empirical data; recent developments in patch-mosaic theory; historical evidence on the effects of fire suppression; and data on indigenous burning strategies, all of which suggest a need to reconsider current fire policy. [ABSTRACT FROM AUTHOR]

Presents information on a study which explored the importance of entomophagy in Africa within the context of food security and indigenous technical knowledge. Nutritional and economic importance of insects; Insect consumption in Sub-Saharan Africa; Methods of collection and gender considerations.

Seasonal climate forecasts have been promoted as a means to increase the resilience of marginal groups in Africa. The manifestations of this are still to be seen. This paper argues that successful dissemination and adoption of the forecast requires an in-depth profile of the characteristics and needs of user groups. The case study of a mountainous village in southern Lesotho is used to highlight the decisions which one group of marginal users – smallholder farmers – might make in response to the forecast. A participatory role-play exercise explores what information households presently receive and how new climate forecast information could be integrated into seasonal decision making. Results show that there are a number of low-input options available to these farmers for responding to the forecast. Adoption, however, is going to require repeated exposure to the forecast in conjunction with forecast development that is suited to users’ needs. The case study is linked back to the larger scale by suggesting paths that seasonal climate forecast development could take if it is to contribute to improving livelihood sustainability among marginal groups. [ABSTRACT FROM AUTHOR]

Presents the results of two complimentary research efforts to analyze the responses of fishing and farming livelihoods to fluctuations in the level of Lake Chad in the Sahara Desert in North Africa. Information on the ecology and agrarian development of Lake Chad; Discussion on the previous researches and fishing and farming livelihoods on the shore of the lake; Analysis using the sustainable rural livelihoods framework.

Since dust storm frequency in the African Sahel is considered an indicator of drought phases, this paper points out basic interrelations of annual and interannual dust storm, rainfall and temperature variability in the region, as well as some large-scale patterns of atmospheric control. The normal seasonal pattern is characterized by a temperature maximum in June/July, a rainfall maximum in August, and a dust storm maximum in April which is linked to a negative soil water budget towards the end of the dry season. However, the dust storm minimum is reached as late as October, i.e. after sufficient soil water infiltration and vegetation cover increase. Thus, seasonal parameter interrelation reflects seasonal shifts in regional atmospheric circulation.Interannual variability, however, seems to occur with periodicities around 2-4 years, 6 years, 11-12 years and 25 years, a result that applies when modelling temperature, rainfall and dust storm series. Further statistical analysis provides insight into the internal structure of the short-term oscillations. Positive springtime dust storm anomalies are preceded by one or two dry years with above-normal summer temperatures. In this case, the evolution of a secondary dust storm maximum in winter is most likely. Over a sequence of 2-3 dry years, dust storm anomalies increase from spring to the following winter.When considering possible atmospheric controls, it was observed that higher summer temperatures in a Sahelian dry year are followed by increased zonal flow in the mid-latitude circumpolar vortex, and colder winters in the Sahel itself. The summer and winter relationship implies these processes to be an effect of meridional transport of excess latent heat after suppression of the West African Walker cell in early summer, and an oversteepened pressure gradient with increased surface trades during the following winter. [ABSTRACT FROM PUBLISHER]

Food is the most basic of the needs of the urban poor in developing countries, and yet relatively little is known about the supply systems through which such needs are met. This is in great contrast to research undertaken on shelter. The urban food supply system is a complex network of production, distribution and consumption linkages, but three main sources of food for the poor may be identified. First, there is the conventional retail sector which has become increasingly dominated by imported commodities and retailing methods, much of which is the consequence of changing dietary preferences and has led to growing food dependency. Not surprisingly, given the cost of food retailed through the conventional sector, the poor have sought alternative sources. The most obvious is through the operations of the petty-commodity or informal sector, but in addition a surprising amount of urban subsistence food is still produced within the cities of Asia and Africa. It would appear that, in general, many authorities still hold repressive attitudes towards the informal or subsistence sectors, largely because their activities spoil the image of the modernizing, Westernized city that the planners wish to convey to the outside world. Clearly, however, these sectors are performing a useful function, but the ways in which and the extent to which their activities benefit the poor is still largely undocumented. It is the argument of this paper that much more information is required on the complexities of the urban food supply system in order to bring about more effective planning to meet the needs of the poor. [ABSTRACT FROM PUBLISHER]

Indicates the variation of purposes for which large-scale irrigation projects are used, and provides details of the economic impact and returns from some such projects in Southern Africa. The paper resulted from a meeting held in the Society's House on February 23, 1989.

Examines the role played by London Missionary Society representatives in the development of geographical debates on the desiccation of the African continent in the 19th century. Influences on the development of desiccationist theory; Ways to acquire information from missionary sources; Patterns of the climatic variability noted by missionaries.