Abstract

Chemical soil degradation after erosion is the second most abundant form of soil degradation and as such poses a threat to our finite soil resource, as it tends to render it less usable. It is therefore necessary to understand the means by which soils are degraded chemically. This review paper seeks to highlight some of the causes of soil chemical degradation. One way by which soils degrade chemically is through soil contamination; either by diffuse contamination or from localised sources. Drivers such as salinization, acidification of soils, chemical fertilizer application and use of pesticides all tend to aid the process of soil chemical degradation. The review paper sheds light on these drivers of degradation and also discusses some assessment methods developed to determine soil chemical degradation. In assessing chemical degradation, a combination of assessment tools and soil quality indicator parameters or single assessment tools may be employed. Some of these tools include ecotoxicological approach, soil quality test. A combination of two or more assessment tools aids in the process of restoration of the soil. Chemically degraded soils may be irreversible in most cases and as such its prevention will aid in agricultural sustainability.

Key words: Diffused contamination, localised contamination, soil assessment, soil health, soil quality.