Beyond Biophysical Recommendations: Towards a New Paradigm

Abstract

African soils have an inherently poor fertility because they are very old and lack volcanic rejuvenation. Inappropriate land use, poor management and lack of input have led to a decline in productivity, soil erosion, salinization and loss of vegetation.

The extent of such losses is of sufficient importance that action, such as ­recapitalization of soil fertility, increased use of inorganic fertilizer, and more efficient recycling of biomass within the farming system are being taken. For this reason, several long-term soil fertility management trials have been conducted in Africa to enable appropriate agronomic recommendations. Despite the need for increasing productivity, the average intensity of fertilizer use in SSA, excluding South Africa, is about 9 kg/ha. The diagnostic studies of fertilizer use in Africa have suggested that fertilizer use is low in Africa for four interrelated reasons: (1)

• The low returns to fertilizer use due to agro-climatic conditions and current ­farming methods;

• (2) The lack of information about fertilizer among retailers, farmers, and extension agents such as price information and best practices;

• (3) The high costs of fertilizers due to foreign production, large units, and costly transport; and

• (4) The inconsistent and adverse policy environment such as shifting government and donor subsidy policies that undermine private investment. This calls for a shift in paradigm to ensure adoption of the appropriate technologies emanating from long-term experiments and to realize the much needed green revolution in Africa. A critical lesson from previous paradigms is that a highly context-specific approach is required which takes into account the fertility status of the soil, the availability of organic inputs and the ability to access and pay for mineral fertilizers. However, making the necessary investments in soil fertilization to derive benefits including adequate returns on investments depends on output markets and the market value of farm products. This varies across Africa, within regions and even within villages and fields.