邦德代写Assignment:污染

There are many different sources for soil pollution such as, seepage from a landfill, discharge of industrial waste into the soil, leakage of contaminated water into the soil, leakage of underground storage tanks, excess application of pesticides, herbicides or fertilizer and solid waste seepage [6]. However, the most common chemicals that cause soil pollution are: petroleum hydrocarbons, heavy metals, pesticides, organic solvents, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorinated aromatic compounds, as well as inorganic compounds, such as nitrates, phosphates, inorganic acids and radioactive substances [7]. Soil is an extremely important resource for human beings, not only because it impacts our agriculture directly, but also since it affects domestic animals that are crucial to our survival. As would be expected, good soil health improves the productivity of agricultural crops. By definition, soil health is the capacity of soil to function as a vital living system, within an ecosystem and land use boundaries, to sustain biological productivity, promote the quality of air and water environment, and maintain plant, animal, and human health [6-7].The importance of soil is further highlighted by the fact that soil works as an environmental filter to remove various toxic substances [7]. It is also worth pointing out that since regeneration of soil by chemical and biological processes takes a very long time, soil is considered to be a very precious, non-renewable resource. it is believed that one components of soil that is most susceptible to soil pollution are the microorganisms that are present in soil