Africa needs agroforestry to cut forest emissions
Growing trees among crops could sustain both environments and livelihoods in Africa, say F.K. Akinnifesi, B. Muys and O.C. Ajayi.
The conflict between conserving environments and improving livelihoods is constricting efforts for reducing emissions from deforestation and forest degradation (REDD) in Sub-Saharan Africa. But agroforestry — managing trees with agricultural production — could help.
The Financial Times calls the carbon market the world's fastest growing commodity market — with agriculture, forestry and other land use playing an increasingly important role. The idea behind REDD is simple — pay countries to reduce carbon emissions from deforestation and degraded lands.
But working out practical solutions that meet key Millennium Development Goals — namely, to end extreme poverty and hunger, and ensure environmental sustainability — remains difficult.
More trees, better livelihoods
Developing countries' quest for food security through agricultural expansion often leads to deforestation and forest degradation. The main challenge for much of Sub-Saharan Africa is how to design agricultural landscapes to resolve livelihood-environment conflict and maintain forests' ecosystem benefits such as water storage, erosion control, biodiversity conservation and soil rehabilitation.
The way forward is to integrate climate and livelihood, adaptation and mitigation, REDD and agriculture. Agroforestry should be a key component of this approach. Integrating trees into agricultural landscapes on a massive scale would create an effective carbon sink while ensuring sustainable food production, and would help adapt to climate change in other ways too.
Tree-based systems are much better at accumulating carbon, above and below ground, than pure agriculture. A 'green investment' project in India has demonstrated how to harness tree planting for carbon off-setting (see Growing money on trees?). Tree and carbon experts from the World Agroforestry Centre suggest that a billion hectares of farmland (much of it in developing countries) could be turned into carbon-rich agricultural landscapes, potentially sequestering 50 billion tonnes of carbon dioxide — a third of the carbon reduction challenge.
Of course, saving carbon is not usually the top priority for small-holder farmers— but agroforestry can contribute many of the other benefits farmers want too. For example, a meta-analysis of 94 scientific publications — conducted by World Agroforestry Centre researchers and published in Plant and Soil in 2008 — indicates that using 'fertiliser trees' that capture nitrogen from the air and transfer it to the soil can reduce the need for commercial nitrogen fertilisers by 75 per cent while doubling crop yields. If combined with other soil fertility management, such as conservation agriculture, fertiliser trees can significantly boost sustainable soil health and increase food security. A diverse tree cover can also increase agroecosystems' resilience towards drought, pest and disease and other threats on food production induced by climate change.
Stream of benefits
If REDD — or indeed, any other effort to mitigate climate change — is to succeed, it must recognise rural livelihood priorities and focus on providing a 'stream of benefits'. Agroforestry tree planting offers this, from tree products such as fruits, medicines and wood to ecosystem benefits such as pollination, water storage and erosion control.
Deliberately creating opportunities for non-timber tree products is a robust way of reducing risks and diversifying options for agroforestry. But this will require putting the right trees, markets, policies and institutions in place.
Another challenge for local communities in the South is getting paid for the carbon they sequester. Experience shows that qualifying and registering for initiatives such as the Clean Development Mechanism (CDM) — and, more likely than not for REDD — involves technical hurdles that hinder wide participation by land users from the South. Excellent toolkits, such as the EU-funded project for designing CDM forestry projects, ENCOFOR, can help. The World Agroforestry Centre is also helping develop capacity to use satellite data and new hi-tech measurement techniques to remotely calculate carbon stocks across millions of square kilometres of agricultural land and forests. Nevertheless, the challenges remain.
Carbon off-setting schemes such as REDD could both improve the environment and generate income. We believe the sustainable landscape of the future in Sub-Saharan Africa will have to be tree-based to guarantee achieving the dual goals of sustainable livelihoods and environments. But we must urge policymakers to recognise agroforestry as an important win-win solution.
The first steps will be to scale-up existing proven and integrated tree-based practices such as combining conservation agriculture with agroforestry on farmlands — what we now call "evergreen agriculture" — to achieve 'high carbon stock' and sustainable food security and livelihoods. This will need sound decision support mechanisms from researchers — supported by policymakers for effective implementation —that build on knowledge, partnerships and capacity at all scales. It also involves providing start-up inputs of quality seeds, nursery, training and extension materials, product markets, carbon credits, payment for environmental services and other financial stimuli for farmers.
F.K. Akinnifesi and O.C. Ajayi are researchers at the World Agroforestry Centre. They are based in the Southern Africa Programme, at Chitedze Agricultural Research Station in Malawi.
B. Muys is a professor at KLIMOS (Research Platform Climate & Development), Katholieke Universiteit Leuven, in Belgium.