Akinwumi A. Adesina

Econometric analysis of the determinants of adoption of alley farming by farmers in the forest zone of southwest Cameroon.

Abstract Slash-and-burn agriculture continues to expand in many parts of the forest zone of Cameroon. One alternative land use to slash-and-burn system is alley farming. This paper quantifies, using an econometric model, the factors determining farmers’ adoption and use of alley farming variants in southwest of Cameroon, based on a survey of 156 farmers in 11 villages in the region. The analysis showed that male farmers are more likely to adopt than women. Adoption is higher for farmers with contacts with extension agencies working on agroforestry technologies. Adoption is higher for farmers belonging to farmers’ groups. Adoption is lower for farmers in areas with very high population pressure, as farmers in such areas may have greater labor productivity from use of less labor intensive natural resource management technologies like chemical fertilizers. Adoption is higher for farmers in areas facing fuel wood scarcity. Farmers have made adaptations to the conventional alley farming technology recommended by researchers, the most significant adaptation being the introduction of fallow periods into the system. Farmers use alley farming as a land use option, not as a replacement for the slash-and-burn system, since land supply is still relatively elastic. Achieving increased impact with alley farming variants requires effective targeting. Results showed that econometric modeling using farmer and village characteristics, socioeconomic and institutional variables can lead to more effective targeting to farmers and locations where higher adoption rates may occur.

Determinants of chemical input use in peri-urban lowland systems: bivariate probit analysis in Cameroon

Abstract Low use of chemical inputs has been cited as a major factor limiting productivity growth of agriculture in most of sub-Saharan Africa. A wide range of variables influence adoption of such input. It is important to understand the role of these factors to ensure the development and implementation of more effective programs to promote agricultural input use. This study examines the effect of socio-economic factors on the likelihood of using chemical fertilizer and pesticide in peri-urban lowland agricultural systems in Cameroon. Rather than the univariate probit model which is commonly used, the bivariate probit model is employed to take account of the correlation between the disturbances. Results generally indicate that lowland farmers who are more highly educated, those with temporary land rights and those whose fields are more distant from the homestead are more likely to use chemical fertilizer. In the same way, lowland male farmers, those who have contact with extension, those who have temporary land rights or those practising continuous cropping are more likely to use chemical pesticides.

Building an Alliance for a Green Revolution in Africa

Most of Africas people live in rural areas and depend on agriculture for their livelihoods. These predominantly small‐scale farmers face many challenges, including food insecurity, rising poverty, and natural resource degradation. To increase the productivity, profitability, and sustainability of their farms, they need greater access to affordable yield‐enhancing inputs, including well‐adapted seeds and new methods for integrated soil fertility management, as well as to output markets where they can convert surplus production into cash. To address these needs, the Rockefeller Foundation and the Bill and Melinda Gates Foundation established the Alliance for a Green Revolution in Africa (AGRA). AGRA is now African led and is working within the context of the comprehensive agricultural development program established by Africas leaders. From offices in Nairobi, Kenya, and Accra, Ghana, AGRA will support work across all key aspects of the African agricultural value chain to help millions of small‐scale farmers and their families lift themselves out of poverty and hunger.

Soil fertility decline at the base of rural poverty in sub-Saharan Africa

To the Editor — Pedro Sanchez1 sketched a very optimistic picture for the future of food production in sub-Saharan Africa, and rightfully so. However, he did not stress the need to care for soils, many of which are degraded in this part of the world. This omission of soil management is unfortunate, but far from exceptional; hence, the declaration of 2015 as the International Year of Soils. Here, we outline the importance of soils for the alleviation of poverty in subSaharan Africa. Traditionally, fields have been left fallow for a number of years, so that the natural vegetation can regrow and soil fertility can be restored. But with increasing population densities and associated demands for land, the practice of leaving land fallow is no longer an option in many areas of subSaharan Africa. As a result, soil degradation processes have intensified. Soil nutrient mining is the most common form of soil degradation, and results in less crop productivity, less biomass and less soil cover, thereby exacerbating other soil degradation processes, such as erosion, acidification and the formation of hard pans (dense soil layers that are largely impervious to water infiltration and root growth). Soil degradation thus reinforces itself, leading to an increasingly complex set of constraints to crop productivity. Ultimately, soils become nonresponsive and plants growing on such soils are no longer able to capture nutrients applied, for instance in the form of commonly available fertilizers. Low soil fertility is directly linked to low productivity, food insecurity and rural poverty. Food insecurity and poverty, in turn, can cause rural-to-urban migration, increased food importation bills (which compete with investment in agricultural development), and an increased reliance of rural communities on remittances sent from family members living in towns or abroad. Hence, we stress the immediate need to reverse soil degradation before it becomes unachievable and many African smallholder farmers become locked in a poverty trap. Nutrient imbalances can be remedied relatively quickly through the application of fertilizer or other sources of nutrients. Recently published data show average fertilizer nutrient application rates of 64, 56, 25, 8, 2 and 1 kg ha–1 for Nigeria, Malawi, Ethiopia, Tanzania, Niger and Uganda, respectively2. Independent FAO data3 show increases in maize productivity between 2000 and 2013 of 39, 93, 120, 27, 12 and 84 kg year–1, respectively, suggesting larger increases in maize productivity in countries where more fertilizer is used. However, nutrient application should be targeted to responsive soils, and coupled to additional measures designed to improve soil health, and ultimately yield, including the use of improved germplasm and available organic inputs4. In cases where nutrient mining has given way to more complex constraints, longer-term soil rehabilitation measures are needed. Such measures include subsoil tillage to remove hard pans, the application of large quantities of high quality manure to alleviate soil chemistry constraints such as cation imbalances, or the application of lime to eliminate aluminium-related constraints. Soil rehabilitation can restore degraded soils, rendering them responsive to fertilizer addition5, but may require incentives because of the limited financial means of most smallholder families. Commitment to maintaining and restoring the soil resource in sub-Saharan Africa can be fostered by ensuring that farmers have access to affordable agroinputs, and by ensuring that the institutional environment — such as access to credit, appropriate rural infrastructure and profitable output markets — allows farmers to gain an income from their produce and re-invest in soil health. As Sanchez1 pointed out, many interventions are needed along the whole food value chain, but we cannot forget that agricultural development starts with a healthy soil producing a healthy crop. ❐