Soils, sinks, and smallholder farmers: Examining the benefits of biochar energy transitions in Kenya

Yahia Mahmoud,Mary Njenga,Cecilia Sundberg,Kristina Roing De Nowina

doi:10.1016/j.erss.2021.102033

Abstract

Besides reducing fuel demands and indoor air pollution, pyrolytic cooking stoves produce a by-product (biochar) that can improve soil fertility and serve as a sink for carbon sequestration. Most smallholder farmers in Africa depend on wood for fuel, suffer from exposure to smoke and soils in their cultivated farms are deteriorating. Biochar (bio-charcoal) production has potentials to reduce energy requirement, diminish exposure to smoke, improve soil health and ease household activities traditionally associated with female labour. However, introducing new technologies and behaviours that tackle existing problems without creating new ones is a complex endeavour. Transitions need to be anticipatory, comprehensive and inclusive. Having this in mind, a trans-disciplinary study was conducted from 2013 to 2019 with 150 households in three agro-ecological zones of Kenya. The socio-economic conditions, the uses of fuels and stoves, the crops grown and fertilizers used, as well as the labour division within households were documented. Selected households were given pyrolitic cooking stoves and trained in applying biochar to the soil. After two years of using the cooking stoves and applying biochar, studies were conducted to assess the feasibility and preliminary impacts based on the households own perceptions and experiences. The results showed that the strategy represented a viable option to deal with fuel use efficiency, exposure to indoor smoke and soil degradation, as well as easing the burden on female labour.

Highlights

Soil degradation, diminishing fuel sources and unhealthy cooking techniques are distinctive features affecting most poor households in rural Africa
We explored the strategy of using gasifier cooking stoves that reduce feedstock demands, minimize exposure to indoor cooking smoke and produce biochar for soil amendment purposes
We provide an overview of the socio-economic conditions at the onset of the project to evaluate the need for experimenting with biochar, the communities’ willingness to adopt it and the benefits it might bring

Summary

Introduction

Soil degradation, diminishing fuel sources and unhealthy cooking techniques are distinctive features affecting most poor households in rural Africa. Soil degradation and its numerous consequences are a global concern, but the impacts on African smallholders is a pressing matter [1,2,3,4,5,6,7]. Traditional fuel sources such as firewood, the dominant fuel-energy source in rural Africa, are becoming scarce in most parts leading to undesirable impacts on both people and ecosys tems. The dominant cooking tech niques in rural Africa have been associated with the negative health impacts, on women and children [12,13,15,16,17]. We explored the strategy of using gasifier cooking stoves that reduce feedstock demands, minimize exposure to indoor cooking smoke and produce biochar for soil amendment purposes

Objectives

Methods

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Discussion

Conclusion