Soil is Not Sexy But it’s What Really Matters in Africa

This year’s Climate and Society class is out in the field (or lab or office) completing a summer internship or thesis. They’ll be documenting their experiences one blog post at a time. Read on to see what they’re up to.

Yanni Zhan, C+S ’16

Much of the Sub-Saharan Africa suffers from poor soil, poor crops, poor water quality and poor livestock health. These all contribute to poor human health and stagnant economic development. There have been very few changes in farming practices over the last 30 years in the region largely because farmers are trapped in poverty. This is leading to increasing food insecurity, water scarcity and environmental degradation. What can be done to change this situation? The answer lies in the soil itself.

Vital Soil: Addressing Root Issues in Africa

Soil is the base of almost everything. You know it can be used to grow crops, but it does much more than that. Soil — in particular healthy soil — is as essential as the air and water that sustain us. If there were no soil, there would be no crops, no clean water, no clean air and no clouds.

Cracked Africa. Source: FutureAtlas.com

Unfortunately, many African landscapes are characterized by poor soil health, leading to low crop yields. That can in turn leave farmers with little or no extra money for fertilizer to enhance productivity, which in turn worsens the soil health, creating a vicious cycle of poverty.

Improving soil health is crucial to improving agricultural return on investments and reducing poverty and hunger.

Crops are not all the same, though. Although they all need nutrients, they have different nutrients requirements. As a result, when measuring the soil, it is important to take into account the texture, depth, organic matter, nutrient level and pH levels. Knowing specific soil properties make it possible to know what plants the soil can support, how water moves in the ecosystem, how the soil affects the decomposition and nutrients cycling, and what organisms can survive in it.

Degraded Soil

Soil is sometimes overtaxed and under-nourished. Deforestation and overgrazing, for example, prevent the ground from its natural recovering process. When the plants and roots systems are gone, soil is exposed to more runoff from rainfall, which increases erosion and sweeps away the soil’s nutrients. The unhealthy soil cannot perform the regular provisioning and regulation services it supposed to have.

So what can be done when the soil is degraded?

Soil health or soil degradation is not a one-way street. On the one hand, human can degrade soil very quickly. On the other hand, stewardship of the land and proper management can improve soil conditions. The key to improve soil health, especially ones that have been degraded, is to make sure the nutrient cycle is restarted and returns to something that resembles a natural cycle. This also means that agricultural practices have to be optimized and the key component to that is organic matter or plant biomass going back into the soil, which can improve the fertility of the soil and the soil structure.

African photosynthetically active biomes (forests and rangelands) map, 2016. Source: Africa soil information services

A New Plan for Africa’s Soil

Traditional soil maps are limited by their incompleteness, inflexibility and coarse scale. We need to provide Sub-Saharan African areas with updated 21st century technologies to get information in the hands of farmers, policy makers and basically everybody.

Recent years have seen enormous developments in technologies that make a new kind of digital soil map possible. It is more useful to everyone from policymakers to the farmers themselves. By definition, we are now going from the old maps that are very difficult to interpret to a modern system, web-based, accessible to everybody that you can query, interact and would be pretty easy to interpret all the information.