Oluyede C. Ajayi

Evergreen Agriculture: a robust approach to sustainable food security in Africa

Producing more food for a growing population in the coming decades, while at the same time combating poverty and hunger, is a huge challenge facing African agriculture. The risks that come with climate change make this task more daunting. However, hundreds of thousands of rain fed smallholder farmers in Zambia, Malawi, Niger, and Burkina Faso have been shifting to farming systems that are restoring exhausted soils and are increasing food crop yields, household food security, and incomes. This article reviews these experiences, and their broader implications for African food security, as manifestations of Evergreen Agriculture, a fresh approach to achieving food security and environmental resilience. Evergreen Agriculture is defined as the integration of particular tree species into annual food crop systems. The intercropped trees sustain a green cover on the land throughout the year to maintain vegetative soil cover, bolster nutrient supply through nitrogen fixation and nutrient cycling, generate greater quantities of organic matter in soil surface residues, improve soil structure and water infiltration, increase greater direct production of food, fodder, fuel, fiber and income from products produced by the intercropped trees, enhance carbon storage both above-ground and below-ground, and induce more effective conservation of above- and below-ground biodiversity. Four national cases are reviewed where farmers are observed to be applying these principles on a major scale. The first case involves the experience of Zambia, where conservation farming programmes include the cultivation of food crops within an agroforest of the fertilizer tree Faidherbia albida. The second case is that of the Malawi Agroforestry Food Security Programme, which is integrating fertilizer, fodder, fruit, fuel wood, and timber tree production with food crops on small farms on a national scale. The third case is the dramatic expansion of Faidherbia albida agroforests in millet and sorghum production systems throughout Niger via assisted natural regeneration. The fourth case is the development of a unique type of planting pit technology (zai) along with farmer-managed natural regeneration of trees on a substantial scale in Burkina Faso. Lastly, we examine the current outlook for Evergreen Agriculture to be further adapted and scaled-up across the African continent.

Fertiliser trees for sustainable food security in the maize-based production systems of East and Southern Africa. A review

The negative effects of soil fertility depletion on food security, especially among smallholder farmers in Africa, is of economic importance, and may be worsened by climate change and rising global fertiliser prices. Substantial efforts and investment have gone into development of alternative soil fertility management options. These include vigorous research and development of N-fixing plants or “fertiliser trees”, that has been on-going in the last two decades in East and Southern Africa. In this paper, we review several studies conducted both on-station and on-farm and synthesise the results in terms of improvements in soil physical, chemical and biological properties, and crop yield in response to fertiliser trees. Our major findings are that (1) fertiliser trees add more than 60 kg N ha−1 per year through biological nitrogen fixation (BNF); (2) nutrient contributions from fertiliser tree biomass can reduce the requirement for mineral N fertiliser by 75%, translating to huge savings on mineral fertilisers; (3) fertiliser trees were also shown to substantially increase crop yield. A meta-analysis has further provided conclusive evidence that with good management, fertiliser trees can double maize yields compared with local farmer practices of maize cultivation without addition of external fertilisation. (4) Financial analyses showed that fertiliser tree systems are profitable and also have higher net returns than the farmers’ de facto practice, i.e. continuous maize cropping without fertiliser. We conclude that widespread adoption and scaling up of fertiliser trees can reduce the amount of mineral fertiliser needed, maintain the soil ecosystem, and positively impact on the livelihoods of farm households in southern Africa.

Agricultural success from Africa: the case of fertilizer tree systems in southern Africa (Malawi, Tanzania, Mozambique, Zambia and Zimbabwe)

In response to the declining soil fertility in southern Africa and the negative effects that this leads to, such as food insecurity besides other developmental challenges, fertilizer tree systems (FTS) were developed as technological innovation to help smallholder farmers to build soil organic matter and fertility in a sustainable manner. In this paper, we trace the historical background and highlight the developmental phases and outcomes of the technology. The synthesis shows that FTS are inexpensive technologies that significantly raise crop yields, reduce food insecurity and enhance environmental services and resilience of agro-ecologies. Many of the achievements recorded with FTS can be traced to some key factors: the availability of a suite of technological options that are appropriate in a range of different household and ecological circumstances, partnership between multiple institutions and disciplines in the development of the technology, active encouragement of farmer innovations in the adaptation process and proactive engagement of several consortia of partner institutions to scale up the technology in farming communities. It is recommended that smallholder farmers would benefit if rural development planners emphasize the merits of different fertility replenishment approaches and taking advantage of the synergy between FTS and mineral fertilizers rather than focusing on ‘organic vs. inorganic’ debates.

Biodiversity of the urban homegardens of São Luís city, Northeastern Brazil

There is a widely held notion that the increasing trend of urbanization accelerates loss of biodiversity and displaces native species. This study assessed the validity of this notion in the city of São Luís the capital of the state of Maranhão in the northeastern Brazil. The specific objectives of the study were to (1) assess plant and animal diversity of urban homegardens, (2) compare the diversity of homegardens in terms of origin of these species (exotic or indigenous to Brazil). We conducted a biodiversity survey in 40 randomly selected ‘quintais’ (hereafter called homegardens) from ten locations in the city of São Luis. We evaluated the species richness and diversity of various use categories of plant and animal species indigenous to Brazil as well as exotic species. A total of 186 species of plants in 68 families were recorded in the sampled homegradens. A total of 63 fruit tree species representing 34% of all tree species were found. Of these species, those indigenous to Brazil accounted for 58% of the cases, and this was significantly higher than the exotic species. Most of the species (60%) were indigenous to Brazil (wild and semi-wild domesticates), while the rest (40%) were exotic. A total of 42 species of vertebrates (mainly reptiles, birds and mammals) were also found in the homegardens, of which 47% were indigenous to Brazil. Some of the plant and animal species found in the homegardens are endangered species in their native habitats, suggesting that homegardens could provide a unique opportunity for their conservation and sustainable use. These species continue to play a vital role in the socioeconomic and ecological landscape of the city.

Do agroforestry technologies improve the livelihoods of the resource poor farmers? Evidence from Kasungu and Machinga districts of Malawi

Fertilizer tree technologies such as intercropping, relay cropping, improved fallows and biomass transfer have been promoted as sustainable, low-input alternative or complimentary inputs to inorganic fertilizers in Malawi. However, research into the long term effects of their adoption on household food security and poverty reduction is limited. This study examined whether these technologies contribute to rural household of subsistence farmers in terms of food security and livelihoods improvement in two districts of Malawi. The study shows that fertilizer tree technologies increase crop production and provide additional income to households through sources such as sale of agroforestry tree seed and fuelwood. The choice of the technologies is driven by the size of the land holdings and more benefits are associated with large land holdings. While fertilizer tree technologies contribute to the reduction in hunger months, this is usually compromised at the household level by the inability to achieve livelihood security, absorb and cope with shocks and overall improved welfare.

Agroforestry Tree Seed Production and Supply Systems in Malawi

A sustainable agroforestry tree germplasm supply system is vital to resource-constrained smallholder farmers who depend on agroforestry to improve the productivity of their farm enterprises. Successful adoption of agroforestry hinges on the development of a sustainable agroforestry tree germplasm supply system. This paper reviews the agroforestry tree seed supply system in Malawi, with a view to determining its sustainability and quality. Currently, more than 90% of the documented agroforestry tree seed distributed to farmers is produced by smallholder farmers collected mainly from scattered farmland trees, the remainder being produced from seed orchards and seed stands owned or controlled by research organizations. Three organizations—namely the Land Resources Centre (LRC), National Tree Seed Centre (NTSC) of the Forestry Research Institute of Malawi (FRIM) and the World Agroforestry Centre (ICRAF)—were identified as major procurers of agroforestry tree seed produced by smallholder farmers. Agroforestry germplasm is distributed to farmers by non-governmental organizations (NGOs) and government agricultural and forestry extension departments. The procurement and distribution of germplasm to farmers is in general effective. The major challenge to sustainability of agroforestry tree germplasm distribution in Malawi is dependence on donor funding. The agroforestry tree seed system is, to some extent, sustainable with regards to production, although the genetic quality of the germplasm is low. Germplasm storage facilities at national level are available and possibly adequate, but knowledge and information on effective low-cost tree germplasm storage systems at household level are limited. Sustainability could be enhanced by strengthening of grass-root organizations involved in tree seed production to institutionalize the distribution through farmer–farmer exchange. There is also a need to support the development, promotion and adoption of low-cost tree germplasm storage facilities by smallholder farmers.

Domestication and conservation of indigenous Miombo fruit trees for improving rural livelihoods in Southern Africa

Abstract The last two decades have witnessed increased interest in the conservation, domestication and commercialization of indigenous fruit trees (IFTs) in the tropics. This paper examines the experiences from research and development (R&D) initiatives involving IFTs of the Miombo eco-region. Significant progress has been made in domestication strategies, including species priority setting, provenance trials, participatory clonal selection and development of new cultivars, nursery propagation techniques and field management. New research has created opportunities for the development of IFTs as new crops and their management on-farm. Participatory domestication initiatives described in this paper provide a beneficial strategy aimed at reducing over-dependence and exploitation of wild populations, while at the same time helping farmers and researchers in the development of new tree crops to capture economic opportunities.

Policy Support for Large-Scale Adoption of Agroforestry Practices: Experience from Africa and Asia

Government policies play an important role in facilitating agroforestry promotion. Based on a set of five agroforestry practices that are adopted at a significant scale in different countries of Africa and Asia, we analyze the development path of the different practices and examine how they evolved into widely practiced systems, with the focus on the specific role that government policies had in facilitating such developments. The selected practices were regenerated parklands in Niger, cashew in Ghana, timber planting in India, smallholder fruit production in Kenya, and agroforests in Indonesia. Additionally, major roles of other key actors, such as the private sector, are examined in the light of the current state of knowledge on the policy implications on private sector investments in this field. The study reveals that both government and non-state actors played different roles to encourage the spread of agroforestry. In many cases, the spread of agroforestry was triggered when existing or new policies created market opportunities and increased the economic rationale for adopting given agroforestry systems. Widespread adoption of agroforestry is strongly influenced by the policy and institutional context within which agroforestry is disseminated. Agroforestry was found to be increasingly embedded into national development programs as evidence of its benefits became better known, although a significant number of policy measures disadvantage agroforestry. The study concludes that the dissemination of agroforestry at the farm level should be complemented with conducive policy, institutional and economic incentives. In addition, to ensure a sustained adoption of agroforestry over the long term, policy and dissemination questions will have to be researched with the same vigor that biophysical and farmer levels questions are being investigated.

Opportunity for conserving and utilizing agrobiodiversity through agroforestry in Southern Africa

Abstract Traditional approaches to biodiversity conservation focused on protection of natural habitats in parks and reserves while neglecting the potential to conserve agrobiodiversity in farming systems that could provide other direct and indirect benefits necessary for livelihoods and ecosystem functioning. Quantitative assessments of tree biodiversity have mostly focused on traditional production systems such as shifting cultivation in the miombo ecozone, home gardens and the parkland systems; and to a lesser extent the below ground biodiversity with respect to micro flora and fauna as a function of soil fertility improvement. Agroforestry systems, in contrast to intensive monocultures, may provide high quality habitats for biodiversity conservation. In the case of trees on the landscape, the use of non-timber forest products as a livelihood strategy, particularly for food, nutrition, medicine and ‘safety net’ during lean periods, has been one of the drivers of biodiversity conservation. In southern Africa, research that has addressed biodiversity albeit indirectly include indigenous fruit tree domestication and the screening of multi-purpose tree germplasm for improved agroforestry systems and/or technologies. This paper highlights the state of knowledge on the contribution of agroforestry to agrobiodiversity in southern Africa. It draws on the huge body of data on the genetic diversity of agroforestry trees used to meet diverse livelihood needs including those used for soil fertility replenishment, provision of animal fodder, fruits, medicinal products and, fuelwood and timber.

Certification of agroforestry tree germplasm in Southern Africa: opportunities and challenges

The lack of high quality agroforestry tree germplasm has long been recognized as one of the major challenges to widespread adoption of agroforestry in Southern Africa. Productivity levels realized in operational scale plantings are far less than those demonstrated in research and this has been partly blamed on the use of germplasm of unknown quality and low productivity potential. The lack of high quality germplasm is attributable to the absence of regulations to govern its production in the countries promoting agroforestry. Most of the agroforestry tree germplasm is sold or distributed without regard to its genetic, physiological and physical quality. Given these challenges, in this paper, we reviewed crop seed certification in general and tree germplasm certification in the USA, Europe, India, Southern Africa and the Organisation for Economic Cooperation and Development (OECD) with a view to find potential similarities with agroforestry tree germplasm. Only three countries in sub-Saharan Africa (Burkina Faso, Madagascar and Rwanda) were found to have tree germplasm certification: the OECD Forest Seed and Plant certification scheme. From the review, it is possible to establish agroforestry tree germplasm quality control systems, more so in countries that already have tree seed centres and tree seed regulations. A simple agroforestry tree germplasm certification scheme, based on the FAOs Quality Declared Seed (QDS) with truth-in-labelling is recommended. Three germplasm categories (audit, select and genetically improved) are recommended as a start. Furthermore, countries will need to develop new or amend existing agricultural seed policies and regulations to include agroforestry tree germplasm certification under QDS. Finally, germplasm quality standards for the selected agroforestry trees species in the respective countries will need to be developed.