History Of Bioremediation

Bioremediation is the use of natural microorganisms or plant’s to break down hazardous chemicals into non-toxic or less-toxic substances (“What is Bioremediation”, n.d.).

The prescribed book only provides information of bioremediation to clean up oil, using microorganisms to consume the oil (Botkin & Keller, 2014). Therefore, this paper will provide a broader perspective of bioremediation. Providing a quick history of where it all started, all the different disciplines in which bioremediation can be found and used. Dissolved heavy metals in water, especially stormwater is one of largest cause of water pollution. Bioremediation of soil and water using specific plants and microorganisms, where it was found in recent studies that the Basullis

Natural bioremediation forms part of the carbon, nitrogen and sulphur cycles (Erickson & Davis, 2017). Managed bioremediation, also naturally occurring where steps are taken to implement and manage the system (Erickson & Davis, 2017). The management system is implemented by people, one example is the degradation of sludge, the sludge is spread over the soil where it is managed by controlling the moisture and nutrients in the soil (Erickson & Davis, 2017). Another application is composting, this is the recycling of nutrients into the garden (Erickson & Davis, 2017). In situ bioremediation is treating contaminated groundwater and soil by not excavating or pumping up the water and providing a natural biological treatment in the groundwater (Jørgensen, 2007). The treatment of cleaning the soil or groundwater relies on microbes or plants to break down the contaminants (Jørgensen, 2007). Bioventing is a method of helping along the in-situ bioremediation process by injecting oxygen into the existing soil microorganisms (Dupont,

Phytoextraction: one of the mechanisms in phytoremediation, which is taking out toxic chemicals out of soil or water, mainly heavy metals with a high density. As can be seen, phytoextraction occurs underground as well as by the leaves (Jagtap, 2015).

2. Phyto-stabilization: The process of containing (immobilizing) pollutants (mainly heavy metals) within the unsaturated zone (Bolan, et al., 2011) (the unsaturated zone, or better known as the vadose zone, is the area between the top soil and the groundwater table (encyclopaedia brittanica, n.d.)). The pollutants are kept in the roots of the plants and directly reducing the possibility of contaminating off-site soils (Bolan, et al., 2011).

3. Phytodegradation: The process of plants taking up contaminants and breaking it down by means of the plant’s metabolism, or the contaminants can be broken down by the enzymes that are surrounding the plant (Chyn, 2011) (enzymes is a biological catalyst, which accelerates the chemical reaction).

4. Phyto-stimulation: when the roots of the plant release chemicals which encourage microbial activity in the unsaturated zone in the soil (Rydberg, 2005).

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5. Phyto-volatilization: the uptake of pollutants, mainly organic compounds, where the pollutants move through the plant’s roots, where it is released into the atmosphere as vapour (EPA,