Review on Chemical Soil Degradation as a Result of Contamination (Published)
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. Chemically degraded soils may be irreversible in most cases and as such its prevention will aid in agricultural sustainability. The cultivated lands are continuously degrading and the extent is increasing because of different natural environmental and anthropogenic activities. Soil degradation due to salinization, erosion, water logging etc. Saline soils can be cultivated growing different halophyte plants and using modern irrigation practices. Different amendments can provide calcium directly to the soil or indirectly dissolving native calcium from calcium carbonate already resent in the soil. Different studies demonstrate that under adverse conditions where chemical treatments are uneconomical tree plantations provide positive net returns to investment and significant net benefit and social outcomes from these lands.
Keywords: Acidification, Diffused contamination, Salinization, Soil Quality, localised contamination, soil assessment, soil health