The effects of soil bunds on runoff, losses of soil and nutrients, and crop yield are rarely documented in the Central Highlands of Ethiopia. A field experiment was set up consisting of three treatments: (i) barley‐cultivated land protected with graded soil bunds (Sb); (ii) fallow land (F); and (iii) barley‐cultivated land without soil bund (Bc). For 3 years (2007–2009), the effect of soil bunds on runoff, losses of soil and nutrients, and crop productivity was studied. Daily runoff and soil and nutrient losses were measured for each treatment using standard procedures while barley yield was recorded from the cultivated plots. The results showed that Sb brought about significant reduction in runoff and soil losses. Plots with Sb reduced the average annual runoff by 28 per cent and the average annual soil loss by 47 per cent. Consequently, Sb reduced losses of soil nutrients and organic carbon. However, the absolute losses were still high. This implies the need for supplementing Sb with biological and agronomic land management measures to further control soil erosion. Despite these positive impacts on soil quality, Sb do not increase crop yield. Calculated on a per‐hectare basis, Sb even reduce crop yield by about 7 per cent as compared with control plots, which is entirely explained by the reduction of the cultivable area by 8·6 per cent due to the soil bunds. Suitable measures are needed to compensate the yield losses caused by the construction of soil bunds, which would convince farmers to construct these land management measures that have long‐term beneficial effects on erosion control. Copyright © 2012 John Wiley & Sons, Ltd.

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The World Food Summit in 1996 set the goal of reducing by half the numbers of malnourished people in the world by 2015. It is unlikely that this will be reached, and particularly not in Sub-Saharan Africa (SSA). Food imports in SSA have increased in the past 40 years, since domestic production could not keep up with population growth. Several studies have reported about this stagnating food production in SSA. However, this region encompasses a large number of countries, with a great variety of agroecological zones and large differences in land, labour and other resources. The objectives of this paper are to analyse agricultural production and food security in eight countries in Sub-Saharan Africa over the past 40 years, and to investigate to what extent these countries have followed different agricultural development pathways and are faced with different constraints. The analysis is largely based on statistical data, mainly from FAO, and on other information from various national and international sources. It shows that some of these countries have struggled to achieve and maintain overall national food security, while others have been able to achieve more than that and increased production at a faster rate than population growth. It subsequently analyzes major development constraints, with regard to labour, land and water, and institutions, pinpoints certain positive developments that have taken place in some of the countries and looks at opportunities for the respective countries to improve their food situation. One of its conclusions is that more attention should be paid to country specific constraints and opportunities.