Soil pollution

The introduction of substances, biological organisms, or energy into the soil, resulting in a change of the soil quality, which is likely to affect the normal use of the soil or endangering human health and the living environment. Substances entering soil that causes soil system pollution in including:

Inorganics

1. Toxic metals, such as Cd, Hg, Cr, Pb, and As etc.

2. Radiation
 

Organics
1. Pesticides

2. Insecticides
3. Herbicides

4. Fungicides

6. Rodenticides
6. Dioxin

Sources of soil pollution

1. Agricultural practices - use of agricultural chemicals, such as herbicides, pesticides and
     fertilizers
2. Industry - regulated industrial waster landfilling
3. Urban activities - regulated domestic waster landfilling, irrigation of domestic waster
    water

Soil pollution effects
1. Deteriorating soil quality, such as losing natural nutrient, reducing nitrogen fixation
   capability, Increased soil erosion and salinity
2. Imbalance of soil ecosystem
3. Increasing risk of agricultural product safety

Soil pollution source control
1. Minimising the use of agricultural chemicals
2. Ban on toxic chemicals and production of green chemicals
3. Production and use of natural fertilizers
4. Improving waster water and waste solid treatment techniques
5. Upbringing public awareness to get proper recycling and reuse of domestic wastes.
 
Soil pollution control techniques
1. Improving cropping techniques to prevent growth of weeds
2. Excavation or dredging

Soil remediation technologies
1. Thermal adsorption
2. Soil vapour extraction
3. Phytoremediation
4. Bioremediation