Global extent, development and economic impact of acid soils
Acid soils occupy approximately 30% or 3950 m ha of the world’s ice free land area and occur mainly in two global belts where they have developed under udic or ustic moisture regimes. 
Nitrification in acid soils: micro-organisms and mechanisms
Nitrification in acid soils was first reported in the beginning of the 20th century. Although this finding has been well substantiated by countless studies since then, it has until recently remained unclear which micro-organisms were responsible for nitrate production at low pH. Substantial evidence now supports the role of chemolitho–autotrophic bacteria as the main nitrifying agents in most acid soils. 
Mechanisms of adaptation of plants to acid soils
Major constraints for plant growth on acid mineral soils are toxic concentrations of mineral elements like Al, of H+, and/or low mineral nutrient availability either as a result of solubility (e.g. P and Mo), low reserves, and impaired uptake (e.g. Mg2+) at high H+ concentrations. Inhibition of root growth particularly by Al leads to more shallow root systems, which may affect the capacity for mineral nutrient acquisition and increase the risk of drought stress. 
Lime-Aluminium- Phosphorus Interactions in Acid Soils of the Kenya Highlands
Liming and phosphorus (P) applications are common practices for improving crop production in acid soils of the tropics. Although considerable work has been done to establish liming rates for acid soils in many parts of the world, information on the role of the lime-Al-P interactions on P fertility management is minimal. 
Influence of Agricultural Lime on Soil Properties and Wheat (Triticum aestivum L.) Yield on Acidic Soils of Uasin Gishu County, Kenya
A study was carried out to investigate the influence of agricultural lime (21% CaO) from Koru, Kisumu on soil properties and wheat yield on acidic soils of Uasin Gishu county. Field trials were conducted at Chepkoilel University College farm and in Kipsangui area of Uasin Gishu county. Soils were analyzed to determine their pH, available P and other nutrient levels before treatment application. 
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 M. Muindi, E., P. Mrema, J., Semu, E., W. Mtakwa, P., K. Gachene, C. and K. Njogu, M. (2015) “Lime-Aluminium- Phosphorus Interactions in Acid Soils of the Kenya Highlands”, Journal of Experimental Agriculture International, 9(4), pp. 1-10. doi: 10.9734/AJEA/2015/20220.
 A. Osundwa, M., R. Okalebo, J., K. Ngetich, W., O. Ochuodho, J., O. Othieno, C., Langat, B. and S. Omenyo, V. (2013) “Influence of Agricultural Lime on Soil Properties and Wheat (Triticum aestivum L.) Yield on Acidic Soils of Uasin Gishu County, Kenya”, Journal of Experimental Agriculture International, 3(4), pp. 806-823. doi: 10.9734/AJEA/2013/3446.