I am Mercy Nyambura, the Laboratory Manager of the Soil-Plant spectral diagnostics laboratory at the World Agroforestry Centre (ICRAF), Nairobi, Kenya. I am also a PhD student attached to FoodAfrica work package no 1 focusing on soil research. The PhD study is at the University of Nairobi in Kenya, a FoodAfrica partner in the WP1. Other partners are the MTT Agrifood Research Finland, ICRAF and the James Hutton Institute (JHI) from Scotland.
My research is on the Nutrient status and mineralogical composition in Africa’s soil: an application of X-ray diffraction and associated analytical methods. In this study I will establish the relationships between nutrient status of Sub-Saharan Africa soils and soil mineralogical composition using new diagnostic analytical methods based on non-destructive X-ray and infrared spectroscopy for improved plant, animal and human nutrition; testing the statistical power of combinations of their data to understand and predict soil fertility and micronutrient reference values.
In my first year of the study I got an opportunity to visit the two partner institutes; MTT Agrifood Research Finland and the James Hutton Institute in Aberdeen, Scotland. During my two weeks visit in Finland I learnt more about the MTT international strategy, its research for development theme, and a brief on the several ongoing MTT projects during the orientation tour. I spent most of the time at the MTT’s Soil and Plants nutrition research unit, headed by Prof. Martti Esala. Working in the well-equipped laboratory facilities gave me an exposure to the techniques and methods for soil and plant analysis, the soil archive systems and library resources. I was also able to visit MTT’s partners; University of Helsinki, Faculty of Agriculture and Forestry laboratory and the Viljavuuspalvelu laboratories in Mikkeli. This trip was very useful and I was able to develop the write up for my study with ease and a good background exposure. I will be using the MTT Agrifood research laboratories AAAc-EDTA extraction methods to determine easily soluble Cu, Fe, Mn, Zn, Al, Cd, Mo, Ni, Pb, V and Se, and soluble B by hot water extraction. These data will be used to calibrate the spectral techniques used at ICRAF. Spectral techniques are methods that only use light, allowing us to diagnose soil problems cheaply and rapidly.
At the James Hutton Institute, where I was hosted by Dr. Stephen Hillier, I received training on new instrumentation development in high-throughput X-ray diffractometry (XRD) and steady improvements in mineral identification databases and software that can now be applied in quantitative determination of mineral phases on large sample numbers. I have been able to develop a method for quantitative analysis of Africa soil mineralogy using a bench-top X-Ray diffractometer.