Soil fertility in Kenya is in crisis according to a new study showing that more than 95 per cent of smallholder farms have severe depletion of essential soil nutrients: nitrogen, phosphorous and potassium.

All Africa reports on the findings by the National Accelerated Agricultural Input Access Programme (NAAIAP) which also point to dangerously low soil organic matter and acidification in Kenya’s agricultural soils.

While the study tested 9,600 soil samples from 4,800 farms in 42 of the country’s 47 counties, the All Africa article says this is too few to make recommendations for fertilizer use at the farm level given the high variability of soil properties across the country.

What is needed are national-level techniques for “rapid assessment, testing, generation of spatially explicit soil management recommendations and routine monitoring of soil quality,” says the article. This should be backed-up by farm level trials over multiple seasons.

Methods developed by the World Agroforestry Centre in infrared spectroscopy, GIS and Remote Sensing are being successfully applied in Ethiopia to develop high resolution maps of key soil properties such as pH, texture, mineralogy, organic matter, nutrient content, erosion and other soil degradation prevalence estimates. Using this data, Ethiopia will be able to make evidence-based and targeted recommendations on fertilizer applications and water management practices.

In Kenya, it is possible to build a national spectral library for characterizing soil quality at the farm level, drawing on an archive that already exists of soil samples and those analyzed for NAAIP. Further samples could easily be taken by farmers through training them in simple collection and pre-processing techniques. Farmers could then receive a report card on parameters such as organic carbon, nitrogen, soil acidity, soil bulk density, phosphorous, potassium and other essential elements.

Read the full story: Kenya: We Need a Modern Plan to Enrich Soil