Food security and carbon hoofprints

by Georgina Smith | @georginajsmith | CIAT (International Center for Tropical Agriculture)
Tuesday, 21 June 2016 10:18 GMT

* Any views expressed in this opinion piece are those of the author and not of Thomson Reuters Foundation.

At night, Rwanda’s capital Kigali is a sparkling carpet of lights. Yet the tightly packed white beams throw light on a more serious circumstance facing the Rwandan government across the country. Population pressure.

How to feed more people with fewer resources was a topic much deliberated at the Africa Agriculture Science Week last week in Kigali. Rwanda is among the most densely populated countries in the world; its population is expected to double to 26 million by 2050.

Farm plots are already among the smallest in sub-Sahara Africa. Yet with declining plot sizes, it’s not only food security which is at stake; but nutrition security too, say experts.

In Rwanda, reducing carbon emissions from livestock production can’t come at the cost of lowering production – millions of farmers depend on it for their livelihoods.

But farmers need advice so they can make environmental choices that won’t hurt their income or livelihoods. This working paper just released outlines options for integrating forages in Rwandan cropping systems to increase forage production.

In the meantime, research teams are weighing up trade-offs so that Rwanda’s farmers can lower their carbon footprint without lowering their production. One way to do that is to improve feed quality for livestock.

If animals don’t get the right feed, milk yields drop, meat production is low, and methane emissions – a greenhouse gas (GHG) 24 times more potent than carbon dioxide – are high. That’s partly because feed quality also governs methane emissions from enteric fermentation – the digestive process.

To assist decision makers like farmers to weigh trade-offs, the Rwanda Agriculture Board, together with the International Center for Tropical Agriculture (CIAT), the University of Princeton, and CSIRO, are quantifying the impact of intensifying tropical forage production.

Olive Umunezero, an animal nutrition scientist at RAB, explains that her team is gathering data from more than 80 households across different farming systems, to assess food and feed availability, income, soil nutrient balances and GHG emissions.

Working with farmers scattered across the country, the research team follows farmers and livestock twice a month, to find out what they are being fed, and to calculate emissions.

“We measure everything that goes into the feed troughs and check the type of forage,” she says.“Every three months, we get district level data which we analyze,” Olive explains. 

“We check livestock weights and feeding practice to find out what the animals require to deliver expected amounts of milk or meat, and how much methane is emitted.” The data is put into different models, designed to help farmers cut costs, while maximizing production in available space.

“One farmer could be advised to reduce the number of cows and increase goats instead, based on the amount of feed available on his farm,” says Olive. In addition, farmers are advised which forages to use on their farms to combat different challenges.

Using germplasm, sourced from CIAT’s genebank and regional national programs, the forages are adapted to local conditions. “Some forages are better than others,” Olive says.

Some produce higher quantities in a smaller space. Some are better in waterlogged soils – important in swamp areas; some do better in cold weather or are tolerant to specific diseases.

Others, like Brachiaria, have deep rooting systems that increase soil carbon sequestration. In fact, matching the right forages with environmental conditions is a balancing act. It’s one that farmers will need help with – a challenge which researchers are working hard to tackle.

This work was supported by the Norwegian Agency for Development Cooperation (NORAD), CGIAR Research Programs on Humidtropics and Climate Change, Agriculture and Food Security (CCAFS) and Princeton University.