Integrated crop-livestock farming offers a solution to soil fertility mining in semi-arid Kenya: evidence from Marsabit County

Low-input agriculture is prevalent in sub-Saharan Africa but it cannot deliver future food security. Soil nutrients are being mined by small-scale farmers who continue to remove large quantities of nutrients from their soils without using sufficient manure or fertilizer inputs to maintain soil fertility. Declining soil fertility must be addressed in order to achieve sustainable intensification. A large increase in nutrient inputs is seen as a requirement but small-scale farmers face severe constraints in obtaining supplies of mineral fertilizer. Better use of available livestock manure is a possible solution. We present here a case study from Marsabit County in the largest, most arid, and least developed region of Kenya. Evidence was gathered from field studies at four locations during 2016 and 2017 combined with a farmer survey. We show that a typical smallholder farm can achieve satisfactory yields and an acceptable nitrogen balance through better use of available livestock manure. An acceptable balance can also be achieved for phosphorus, however, there is a deficit for potassium. This case study demonstrates that an integrated crop-livestock farming system offers a potential solution to soil nutrient mining and can provide a pathway to sustainable intensification for small-scale farmers in a challenging semi-arid environment.