A recent report by the United Nations states that nearly one-third of the world’s farmable land disappeared from the world in the last four decades and it was hypothesized that within 60 years, all of the world’s topsoil will become unproductive if the soil degradation continues to increase (Maximillian et al., 2019). Soil degradation is described as the loss of soil intrinsic physical qualities, chemical qualities, and/or biological qualities due to either natural sources, anthropogenic sources, or both simultaneously which resulting in many of the important ecosystem functions to become diminished (Nunes et al., 2020) that may eventually lead to the loss of land’s productivity such as soil fertility. Degradation of soil is said to be caused by several problems such as erosion, declining of organic matter, biodiversity loss, compaction and sealing of soil, point-source and diffused contamination, pollution from agriculture, industrial, and commercial, salinization, urban expansion, overgrazing, unsustainable agriculture practices, and also long-term climate change wherein all these causes also act as main threats to the soil’s ecological functions (Montanarella, 2007; Maximillian et al., 2019).

        As the occurrence of soil degradation keep increasing, its severity is said to be dependent on several factors such as the land’s initial status, the magnitude which place pressure on land, the land system responses, and lastly the land resources can be indicate by several factors being visual, physical, chemical, biological, and integrative wherein all these factors are obtained using different methods with visual indicators obtained by field observation or image analysis from satellite, radar, or aerial, with some examples being forest areas and changes in the soil colour (Nunes et al., 2020). As for physical indicators, it is measured through analysing the soil’s solid fractions arrangement with some examples are the soil’s porosity and permeability, while for measuring chemical can be done by monitoring the soil pH, salinity, organic matter content, ion exchange capacity, nutrient cycling, and toxic or radioactive elements presence, and for biological is measuring the macro- and microorganisms’ presence alongside their activities and by products (Strawn et al., 2020; Nunes et al., 2020). The last indicator is integrative indicators, or commonly known as key indicators, is usually done by assessing the soil quality and degradation by using methods such as gathering basic information on the soil’s composition, structure, and the soil system’s functions (Herrick & Wander, 2018; Nunes et al., 2020).

        As mentioned before, soil degradation is mainly caused by natural causes or man-made causes with majority of the increasing case is related to man-made causes such as agricultural and industrial activities with contamination of the soil by heavy metals has become prevalent worldwide with reasons being the world’s rapid industrialization and population growth, thus posing a serious threat towards the environment and humankind if it is not remediated properly and reach higher levels (Abioye, 2011). Heavy metals are natural components found in soils in low concentrations but as of recent years the concentrations have increased rapidly thus becoming worldwide problem due to excessive accumulation of heavy metals such as lead (Pb), chromium (Cr), and mercury (Hg). These heavy metals can enter the food web through plants’ absorption which constitute high risks towards the ecosystem by bioaccumulation through the food web (Gall et al., 2015; Abioye, 2011). However, there are several techniques which have been developed to biologically remediate the soils to avoid any further contamination.

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         Moreover, there are often some confusion and misinterpretation between Soil Pollution and Soil Contamination:

         Soil pollution is known to be when humans introduce harmful chemicals or substances either directly or indirectly into the soil in a way that causes harm to other living things or water ecosystems (Alloway, 2001; Singh, 2020). On the other hand, soil contamination occurs when concentration of chemicals, nutrients or elements in the soil becomes more than it normally or naturally is, as a result of human action. If this contamination goes on to harm living organisms, it is known as soil pollution (Alloway, 2001; Singh, 2020).

         In summary, both soil pollution and contamination are a part of the soil degradation.