Participatory land use analysis for semi-arid regions in Kenya: A nutrient monitoring approach

Abstract

This paper presents a study on nutrient dynamics of typical farms in arid and semi-arid areas in Kenya, using the nutrient monitoring (NUTMON) research approach for assessing nutrient flows and stocks and their effects on financial performance. Systematic collection of information on farm management practices using structured questionnaires allowed quantification of material flows, with emphasis on soil nutrients and cash flows. Based on data collected on inputs into the farm, outputs out of the farm and internal nutrient flows, financial performance indicators are calculated at the farm enterprise level, using the NUTMON toolbox. Participatory soil sampling and laboratory analysis were carried out to determine total N, P, K and carbon stocks in the topsoil layer. Feedback to the farmers was given on the soil analysis results, on the basis of graphs containing the average values for each of the elements (N, P, K and carbon), to identify priorities in alleviating nutrient deficiencies and determine appropriate integrated nutrient management strategies to address soil fertility problems. This led to formulation of a research agenda to combat nutrient constraints during the experimental design workshop. Farmers do associate poor crop yields with poor soil nutrient status and did recognize the relevant symptoms, but not at the level of individual nutrients. Averaged for all farms sampled, total nutrient balances, ie including inputs and outputs over the farm gate, as well as exchange with the environment, such as biological (nitrogen) fixation, leaching and/or volatilization, for N, P and K were negative. The losses in the total balances were mainly due to leaching and erosion, processes that are not under direct control of the farmers. Average net farm income was negative for the clusters operating entirely under rainfed conditions (Kionyweni, Enkorika) and positive for the cluster where irrigation facilities are available (Matuu). In Matuu more than 60% of the farm households have incomes above the rural poverty line, while 90% are below that level in Enkorika.