Review on the Extent of Acid Soil in Ethiopia, Its Impact and Management Methods

Abstract

Soil degradation is a global threat. Developing countries are more severely affected by soil degradation than developed countries. Ethiopia, one of the developing countries in eastern Africa, is highly threatened by soil degradation problems. Soil acidity is one of the main factors that limit and prevent profitable and sustained agricultural productivity in many parts of the world . The objective of this paper is to review the extent of acid soil distributions in Ethiopia, its impact on crop production and management practices. About 40.9% of the total arable land of Ethiopia is affected by soil acidity, from these 27.7% moderately to weak acids with pH 5.8-6.7 and 13.2% covered by strong to moderate acidic soils with pH less than 5.5. According to Ethio SIS, (2014) about 43% of the Ethiopian arable land is affected by soil acidity of these about 28.1% of soils in Ethiopia are dominated by strong acid soils (pH 4.1-5.5). Most of investigators confirmed that the two fundamental factors that limit the fertility of acid soils are: nutrient deficiencies, e.g. phosphorus (P), calcium (Ca) and magnesium (Mg) and the presence of phytotoxicity substances, e.g. soluble aluminium (Al) and manganese (Mn). To overcome these problems, different acid soil management has been implemented in the country. Thus many studies have been conducted with regards to Acid soil management which influences soil physical and chemical properties and crop yield directly or indirectly. Therefore, the aim of this seminor paper is to review different literature on the extent of acid soil in Ethiopia, its impacts on some selected chemical soil properties and management methods. Different studies showed that some soil chemical properties such as pH, Ava_P, OC, CEC, Echangeable Acididy (EA), Excheanchable bases (Ca, Mg, Na and K) and crop yields were improved in different agro ecologies by effects of liming and ISFM. Soil acidity problems also can be overcome by growing crop genotypes which are adapted to acid soil condition. Thus, for sustainable agricultural systems within small-scale farming in developing countries like Ethiopia, use of integrated soil fertlity management, liming and crop varieties tolerant to Al toxicity are  the mechanisms used for management of acid soils.

Key note: Acidity, Lime, ISFM , Acid tolerant crop varieties

DOI: 10.7176/JBAH/9-15-03

Publication date: August 31^st 2019