To grow food you need two things: some land and some of your time. These two - land and labor - are two of agriculture's 'inputs'. To build a food system that works for people and the planet, humanity needs to achieve high productivity in both of them.
To escape poverty, farmers need to increase labor productivity - to produce more food per hour worked. It is a deep societal problem when most of the population works in farming and gets little money in return. The farmers' families are unable to get a good education; improve healthcare; and to free up labor so that their children can become teachers or build new industries outside of agriculture.
To protect the world's wildlife, we need high land productivity - to produce more food per unit of land area. Land productivity for crops is measured as 'crop yields'. If humanity wants to reduce deforestation and protect habitats rich in biodiversity then we need to use less land to grow food.
Across much of Sub-Saharan Africa, the productivity of both input factors is low. Agricultural productivity across the region needs to improve to reduce hunger, poverty, and the destruction of biodiversity. This is why I think that it is one of the most important problems to tackle this century.
Rates of extreme poverty across Sub-Saharan Africa are still very high. While it has made progress in recent decades, 40% of the population still lives below the international poverty line of 1.90 international-dollars per day. This is a very low poverty line, used to identify those in the deepest poverty.
Much of this is explained by the fact that more than half of the labor force work in agriculture, and labor productivity in the sector is poor. Most of the region's poorest people are farmers: The majority (82%) of those in extreme poverty lives in rural areas, and more than three-quarters (76%) of working adults in extreme poverty are employed in agriculture.
These farmers are both producers and consumers. Poverty means that there are not only barriers in food supply, but also in the demand for agricultural products. Farmers need access to local markets where others can afford to buy from them. If that market does not exist, or farmers lack road infrastructure to get there - as has been the case in many African countries - there is less of an incentive for productivity to improve.
This is also due to rich countries' policies towards Africa. Trade policies in other regions have made this even more challenging for African farmers. The EU's agricultural policies, in particular, have received criticism for their impact on global markets. It developed strong trade agreements between EU countries, and at the same time limited export markets for other regions, including Africa.
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We see just how low the productivity is in the chart which compares the amount of agricultural 'value added' per person working in agriculture.
The amount of 'value added' per worker in Sub-Saharan Africa is less than half the global average, and more than 50-times lower than in the countries in which farmers are most productive.
Some countries within Sub-Saharan Africa generate as little as half of this regional average. This makes it impossible for families to escape poverty. Most are smallholder farms. They need family members to work and contribute. They also often cannot afford to invest in education or other opportunities that might allow them to move into industries with higher wages. Without increasing labor productivity, most of the population will have to continue working in agriculture.
The other - strongly-related - problem is that most countries across the region have very low crop yields. We see this in the charts, which compare cereal yields across the world. The average across Africa is half that of India and one-fifth of the yields in the US.
Growing food in this way means using a lot of land; land that would otherwise be habitat for wildlife. Africa's yields have lagged behind most of the world as the time-series chart shows. Most countries have achieved a significant rise since 1961. But across much of Africa, yields have stagnated. As a consequence the global inequality in yields has increased.
Guest Editorial
