Laurent Parrot

Sustainable urban agriculture in developing countries. A review

The population living in cities is continuously increasing worldwide. In developing countries, this phenomenon is exacerbated by poverty, leading to tremendous problems of employment, immigration from the rural areas, transportation, food supply and environment protection. Simultaneously with the growth of cities, a new type of agriculture has emerged; namely, urban agriculture. Here, the main functions of urban agriculture are described: its social roles, the economic functions as part of its multi-functionality, the constraints, and the risks for human consumption and the living environment. We highlight the following major points. (1) Agricultural activity will continue to be a strong contributor to urban households. Currently, differences between rural and urban livelihood households appear to be decreasing. (2) Urban agricultural production includes aquaculture, livestock and plants. The commonest crops are perishable leafy vegetables, particularly in South-east Asia and Africa. These vegetable industries have short marketing chains with lower price differentials between farmers and consumers than longer chains. The city food supply function is one of the various roles and objectives of urban agriculture that leads to increasing dialogue between urban dwellers, city authorities and farmers. (3) One of the farmers’ issues is to produce high quality products in highly populated areas and within a polluted environment. Agricultural production in cities faces the following challenges: access to the main agricultural inputs, fertilizers and water; production in a polluted environment; and limitation of its negative impact on the environment. Urban agriculture can reuse city wastes, but this will not be enough to achieve high yields, and there is still a risk of producing unsafe products. These are the main challenges for urban agriculture in keeping its multi-functional activities such as cleansing, opening up the urban space, and producing fresh and nutritious food.

Municipal solid waste management in Africa: Strategies and livelihoods in Yaoundé, Cameroon

This paper provides an overview of the state of municipal solid waste (MSW) management in the capital of Cameroon, Yaoundé, and suggests some possible solutions for its improvement. The institutional, financial, and physical aspects of MSW management, as well as the livelihoods of the population, were analyzed. Our study revealed that distances and lack of infrastructure have a major impact on waste collection. Garbage bins are systematically mentioned as the primary infrastructure needed by the population in all quarters, whether it be a high or low standard community. The construction of transfer stations and the installation of garbage bins are suggested as a solution to reduce distances between households and garbage bins, thus improving waste collection vehicle accessibility. Transfer stations and garbage bins would enable the official waste collection company to expand its range of services and significantly improve waste collection rates. Several transfer stations have already been set up by non-governmental organizations (NGOs) and community-based organizations (CBOs), but they require technical, institutional and funding support. Research is needed on the quality and safety of community-made compost, as well as on soil fertility in urban and peri-urban areas. Most of the stakeholders, municipalities, the official waste collection company and households acknowledge the need for better monitoring and regulation of MSW management. The urban community of Yaoundé also needs to maintain its support of MSW management and promote the sustainability of NGOs and CBOs operating in underserved areas not yet covered by adequate infrastructures. A major opportunity for implementation of such waste policy is the heavily indebted poor countries (HIPC) program dedicated to urban planning and good governance.

Control of vegetable pests in Benin - Farmers' preferences for eco-friendly nets as an alternative to insecticides

We investigated if eco-friendly nets (EFNs) are a viable and acceptable alternative to extremely high levels of insecticide use in vegetable production. Using a choice experiment, we found that vegetable producing farmers in Benin preferred all of the characteristics of EFNs except the higher labor requirements. The nets had been distributed in a trial phase for free but in the long run farmers would need to purchase the EFNs. The break-even point for investing in nets was found to vary with the lifespan of EFNs, their purchase price and potential health benefits from avoiding large quantities of insecticides. To break even the nets need to be used for at least two production cycles. To overcome risk-averse farmers reluctance to adopt EFNs we propose a credit and warranty scheme along with the purchase of the nets. The studys findings can guide the implementation of EFNs in other African countries as part of integrated pest management with global benefits for the environment and human health.

Sustainable urban agriculture and the adoption of composts in Cameroon

The increased importance of urban agriculture in developing countries suggests reconsidering some innovation adoption opportunities and challenges, particularly soil fertility inputs. In sub-Saharan Africa, urban horticulture uses a high level of soil inputs like inorganic fertilizers, while local composts are far less common. Yet, municipal solid wastes provide high quantity of organic matter, a major component of compost. Our study aimed to determine if urban horticulture in sub-Saharan towns can provide incentives for compost adoption among farmers. To this end, we surveyed 242 farmers in Yaoundé, the capital of Cameroon in the Central Province, and in Bafoussam, a city in the West Province. We used an Ordered Logit Model to test four soil input modalities adopted by farmers and ranging from no soil inputs, composts only, composts and inorganic fertilizers, and inorganic fertilizers only. Our results revealed that 36% of farmers adopt an exclusive or mixed use of compost. Inorganic fertilizer expenditures, vegetable production, land ownership, and land distance simultaneously and significantly influence the four soil input alternatives. Urban horticulture provides the prerequisites for compost adoption in sub-Saharan Africa. We suggest several recommendations for implementation of a waste recycling commodity chain dedicated to agriculture.

Exploring factors that shape small-scale farmers’ opinions on the adoption of eco-friendly nets for vegetable production

AbstractIf agro-ecological systems are to realize their potential as sustainable alternatives to conventional agricultural systems, innovation diffusion needs to be enhanced. We conducted surveys among 214 small-scale vegetable farmers in Benin, a food-deficit country in West Africa, on how they perceived the different attributes of eco-friendly nets (EFNs). The nets act as physical barriers against insects in vegetable production and so reduce pesticide use. Understanding farmer perceptions about new technologies helps reveal farmers’ propensity to adopt them. Intensity of attitude was measured on a Likert scale, and an ordered probit model was used to determine which characteristics of nets were most influential. Eighteen percent of farmers thought that EFNs would benefit them, but almost half preferred not to adopt this technology at all. The main reason for rejecting the nets was the perceived high labor requirement, particularly on larger plots of land. This largely negative perception was strongest among farmers with large areas cultivated with vegetables, farmers who had little or no experience in a trial, and those living far from extension services. We recommend expanded trials that engage a higher proportion of farmers, strengthening of external support for those wanting to use the nets and further technological development to reduce labor costs, improved access to finance and increased education about the negative impacts of insecticides abuse.

Protected cultivation of vegetable crops in sub-Saharan Africa: limits and prospects for smallholders. A review

Vegetable production in sub-Saharan Africa faces numerous agronomic constraints that will have to be overcome to feed the increasing population and to fight malnutrition. Technology transfer and the adoption of low-tech protected cultivation techniques affordable for smallholders are believed to be able to meet this challenge. Protected cultivation techniques are a set of agricultural practices aimed at artificializing the crop environment through the use of soil covers and/or plant covers to control pests and climatic conditions. Although protected cultivation techniques may increase the yield and quality of vegetable crops and extend their production periods worldwide, the transfer of these techniques in sub-Saharan Africa raises questions about their agronomical performances, their profitability but also their environmental impacts. Are low-tech protected cultivation techniques adapted to the sustainable production of vegetables by smallholders in sub-Saharan Africa? To answer this question, we present an overview of the agronomic, economic, and environmental performances of low-tech protected cultivation techniques in sub-Saharan Africa as reported in the literature. The major conclusions that can be drawn from the review are (1) low-tech protected cultivation techniques are not suitable in all climatic conditions in sub-Saharan Africa and need to be combined with other methods to ensure adequate pest control, (2) the profitability of protected cultivation techniques relies on the capacity to offset increased production costs by higher yields and higher selling prices to be obtained with off-season and/or higher quality products, (3) breaking with existing cropping systems, the lack of technical support and skills, and the limited access to investment funding are major obstacles to the adoption of protected cultivation techniques by smallholders (4) life cycle assessments conducted in northern countries suggested that more efficient use of agricultural inputs would offset the negative impacts of protected cultivation techniques if they are properly managed, but further studies are required to be sure these results can be extrapolated to sub-Saharan Africa context.

Inter-supply Chain Recycling of Residues

The absence of relationships – or, worse, the presence of conflicting ones – between segments of various compartmentalized agri-chains that coexist in territories hinders the sustainable development of these agri-chains, and, more broadly, of the territories concerned. This chapter discusses how creating links to the territory by identifying synergies between these agri-chains or with other supply chains could help overcome this limitation. It also presents a set of analyses and conceptions of relationships between local segments of distinct agri-chains using socio-economic analyses and flow analyses. Although there do exist examples of spontaneous inter-supply chain recycling links, they are usually very short circuits, and are often opportunistic and unstable. Moreover, to this organizational instability can be added a less than optimal extraction of value from agricultural output. The analyses presented here suggest that significant potential for linkages between specialized segments of separate supply chains remains untapped, and this at different geographical scales. They also emphasize the importance of organization and coordination, which partly explains why exchanges at supra-farm scales develop rarely without external intervention. We can, however, use techniques to create or strengthen networks between actors from relatively compartmentalized segments on the basis of discovered mutual interests. It is a matter of encouraging industrial symbiosis. In this case, inter-supply chain relationships are seen as value chains that are short, localized, circular, and transversal. A general rule seems to emerge: the more one endeavours to tailor these relationships to contribute to sustainable development, the more complicated they become and the more difficult to build.

Challenges of Poverty, Employment and Food Security

At the global level, family farming is the primary source of employment and the main supplier of food products (Chaps. 3 and 8). It is also, paradoxically, the sector which harbors the largest number of poor people, mainly due to its central place in the economies of many developing countries (IFAD 2011). There are many reasons for this paradox and they must be sought in the heterogeneity of agricultural performance. This heterogeneity results from radical differences between technical systems (Chap. 6) and the economic and institutional environments that result from power relationships built over time within each country’s particular context. These varied histories have led to very different statuses and room for maneuver for family farming systems at the economic, social and political levels.

Defining, Characterizing and Measuring Family Farming Models

Chapter 2 shows that the wide diversity of agricultural forms stems from the political and social structures rooted in historical trajectories, where representations have been forged by power relations and the dissemination of technical progress. This diversity and its reasons invite us to make an effort, necessarily reductive, to define, characterize and measure family farming models, and to clarify what makes them a political and analytical category. To name the production units of the agricultural sector, several categories are mobilized by actors, all of which pertain to different professional spheres but do so in interaction with each other.