Research Team

Case Study Area

Model Evaluation Work

Related Publications

Research Team

The Kenyan case study is being coordinated by Kenya Soil Survey, part of the National Agricultural Research Laboratory (NARL), Nairobi. The Principal Investigators are Dr Stanley Wokabi, Director of NARL and Dr Patrick Gicheru, Head of Kenya Soil Survey. Mr Peter Kamoni is the post doctoral research scientist working on the project.

Case Study Area

The case study covers the whole of Kenya. Kenya borders Somalia and The Indian Ocean in the east, Ethiopia and Sudan in the north and Uganda and Tanzania in the west and southwest.  Kenya covers an area of 582, 646 km² and has a population of ~ 30 million with a population growth rate of 3.3% (Times Atlas 2000). Central and Western Kenya is highly populated especially in the Kissii region and near to Lake Victoria.

TERRAIN There are four major relief zones in Kenya: the coastal and eastern plains, the central and western highlands, the Rift Valley Basin and the Lake Victoria Basin. Elevation ranges from sea level to between 2000 and 3400 m in the highlands.

CROPS The key crops in Kenya are: Tea, Coffee, Banana, Cassava, various tropical vegetables and fruits

SOILS The Major soils (FAO classification) in Kenya in order of abudance are Regosols (unconsolidated soils), Planosols (slowly permeable soils), Solonetzs (sodium affected soils) and Ferralsols (highly weathered soils). In terms of agricultural usage the major soils are Ferralsols, Cambisols, Vertisols and soils with an Argic B horizon (Acrisols, Luvisols, Lixisols and Nitisols).

Model Evaluation Work

Two sets of Kenyon long-term experimental data sets are being used to evaluate the two SOM models for Kenyon conditions. The first of these is a 25 year old fertiliser trial, carried out by the Kenyon National Agricultural Research Laboratory, Nairobi. This study includes 18 different treatments of maize and bean cropping. The second experiment is a 14 year old manure and fertiliser trial which has been carried out in the semi arid area of Kenya.

Related Publications

Kamoni, P.T., Gicheru, P.T.,  Wokabi, S.M., Easter, M., Milne, E., Coleman, K., Falloon, P., Paustian, K., Killian, K., Kihanda, F.M., 2007. ‘Evaluation of two soil carbon models using two Kenyan long term experimental datasets’ In: Milne, E., Powlson, D.S., Cerri, C.E.P. (Eds.), Soil carbon stocks at regional scales. Agric. Ecosyst. Environ., (in press).

Kamoni, P.T., Gicheru, P.T., Wokabi, S.M., Easter, M., Milne, E., Coleman, K., Falloon, P., Paustian, K., 2007. ‘Predicted soil organic carbon stocks and changes in Kenya between 1990 and 2030’. In: Milne, E., Powlson, D.S., Cerri, C.E.P. (Eds.), Soil carbon stocks at regional scales. Agric. Ecosyst. Environ., (in press).

Gicheru P., Gachene C., Mbuvi J. and Mare E. (2004). Effects of soil management and tillage systems on surface soil water conservation and crust formation on a sandy loam in semi-arid Kenya. Soil and Tillage Research, 75 pp173-184