Towards Low Cost Soil Fertility Sensor Systems for Smallholder Food Security in Kenya

Food security is one of the "big four" agenda initiatives championed by the Kenyan Government. More than 80% of Kenya's population is dependent upon agriculture for employment, income, or food security needs (FAO) and a large proportion of the population are food insecure, for example 26% of children under 5 years of age suffer from malnutrition (UNICEF). The food security challenge is intensified by: reducing size of land parcels as a result of population growth; farmers being pushed into dryer lower quality land areas vulnerable to drought; conflicts resulting from competition for land; and people dropping out of nomadic life to move to settled communities dependent upon food aid (FAO).
To address this, increases in agricultural productivity are needed. An important way to improve crop yield relates to better soil fertility. Optimising fertiliser strategies for soil can be summed up as: Right Source, Right Rate, Right Place, Right Time. For the greatest impact, this requires in-field measurement tools that can be used by farmers to understand the spatial changes in nutrient concentration within a field, and how these vary over time. No technology currently exists that allows this to be carried out at very low cost. The alternative to in-field testing is the use of soil laboratories in Nairobi, but these are expensive to use, far away from the farm and provide a single measurement which is not representative of the whole area farmed. In consequence, most smallholders are in the dark about the nutrition status of their soil and how it changes in response to different soil amendment approaches.
This project will help address the measurement challenge by developing a new kind of sensor that can be used by farmers at very low cost to regularly test for two key soil macro-nutrients, called nitrate and phosphate. The project will take inspiration from ancient art and design based printing processes, combined with locally available natural materials (e.g. chimney soot, egg, newspaper and enzymes from plants and bacteria available within Kenya) to make extremely low cost soil sensors. By adopting a "co-creation" based philosophy, the University of Strathclyde in Glasgow, Kenyatta University in Nairobi and Glasgow School of Art in Glasgow will build a collaboration to deliver a step change in sensing technology for smallholder farmers in Kenya. This will be achieved by initially developing the sensor in the UK, employing a researcher from Kenya. Once a proof of concept has been created, the researcher will return to Kenya with the knowledge and understanding to recreate the sensor and test performance in greenhouse trials. The project will also involve a series of workshops where we will engage communities, industry and policy makers to ensure that we create user led solutions to address food security within Kenya.
In the long term, this could be delivered to farmers either as a "factory in a box" containing the tools needed for sensor manufacture, or simply as an information pack that shows how to gather the resources required and print sensors. The project could also influence the wider region: 20 million people across Kenya, Ethiopia and Somalia are food insecure (Worldbank, 2022), and face similar challenges. Parallel benefits also exist for UK innovation, where knowledge and learning from this project could support the manufacture of nature based and zero waste sensors to support UK agriculture and the transition to net zero.