Bioremediation Techniques for Soil Pollution: An Introduction

*Anita Verma*

#### **Abstract**

Environmental pollution has been on the rise in the past few decades owing to increased human activities on energy reservoirs, unsafe agricultural practices and rapid industrialization. Soil pollution is one of the major worry among all because soil contamination can harm the humans by consumption of food grown in polluted soil or it can cause infertility to soil and lower the productivity, Among the pollutants that are of environmental and public health concerns due to their toxicities are: heavy metals, nuclear wastes, pesticides, greenhouse gases, and hydrocarbons. So this chapter will include; Sources of soil pollution and remediation of polluted sites using biological means has proven effective and reliable due to its eco-friendly features. Bio-remediation can either be carried out ex situ or in situ, depending on several factors, which include site characteristics, type and concentration of pollutants. It also seen as a solution for emerging contaminant problems.

**Keywords:** soil pollution, bio-remediation, ex situ bio-remediation, in situ bio-remediation

### **1. Introduction**

Soil is an essential a neighborhood of the common habitat. It's pretty much as significant as plants, creatures, rocks, landforms, loch and waterways. It is a living space for a genuine scope of living beings. It goes about as stream control for water and synthetic substances between the environment and along these lines the world, and furthermore both as a source and store for gases (like oxygen and carbon dioxide) inside the climate. Soils do not simply influence characteristic cycles yet additionally record human exercises both at this and inside the past.

Soil is dynamic organically and a permeable medium that has created inside the highest layer of Earth's covering. Soil is one of the corpus foundations of life on Earth, which might be a supply of water and supplements, as a mechanism for the filtration and breakdown of squanders, and as a functioning member inside the cycling of carbon and different components through the environment accessible universally. It's gotten from enduring cycles driven by natural, climatic, geologic, and geographical impacts.

Soil is the linkage between the different ecosystems like biosphere, atmosphere, and hydrosphere. So, the soils are fundamental in the preservation of environmental quality at local, regional, and worldwide level. For example, its buffering capacity contributes to water quality, since the ability to act as a sink for contaminants

can have an important role in controlling the negative impacts of pollution on other environment. Researchers are trying to develop and model different bioremediation techniques; however, there is no single bioremediation technique that treats all types of contamination and to restore polluted environments. Bioremediation is a natural process, which relies on bacteria, fungi, and plants to remove, reduce, degrade, or immobilize environmental pollutants from soil and water, thus restoring contaminated sites to a relatively clean nontoxic environment [1].

It is now recognized that, soil is considered a vital resource, and due to its slow formation, it can be considered nonrenewable. Moreover, it has impacts on environmental, economic, and cultural activities. These techniques are environmentally friendly and cost effective features are the major advantages of bioremediation compared to both chemical and physical methods of remediation. Thus far, several good definitions have been given to bioremediation, with particular emphasis on one of the processes.

#### **2. Soil pollution**

Soil contamination is that the decrease inside the efficiency of soil in light of the presence of soil toxins. Soil toxins adversely affect the actual substance and organic properties of the dirt and decrease its profitability. Pesticides, composts, natural excrement, synthetic substances, radioactive squanders, disposed of food, garments, cowhide merchandise, plastics, paper, bottles, tins-jars and cadavers all contribute towards causing soil contamination. Synthetic substances like iron lead mercury, copper, zinc, cadmium, aluminum, cyanides, acids and soluble bases and so on are available in modern squanders and arrive at the dirt either straightforwardly with water or in a roundabout way through air. (for example through corrosive downpour).

Soil contamination can cause contamination if harmful synthetics drain into groundwater, or whenever sullied spillover arrives at streams, lakes, or seas. Soil additionally normally adds to contamination by delivering unstable mixtures into the environment. Nitrogen escapes through alkali volatilization and denitrification. The disintegration of natural materials in soil can deliver sulfur dioxide and other sulfur compounds, causing corrosive downpour. Substantial metals and other possibly poisonous components are the principal genuine soil toxins in sewage. Sewage slop contains substantial metals and, whenever applied over and again or in huge sums, the treated soil may gather weighty metals and thus it become incapable to try and support blossoms.
