Friday, September 16, 2011
What is Phytoremediation? Discuss its Applications Civil Services General Studies question paper-II 2010 ( 150 words)
Phytoremediation refers to the use of plants for cleaning up contaminants in soil, groundwater, surface water and air. It is a cost-effective and non-polluting way to remove toxic chemicals that contaminate soil and water and also it offers remediation of brownfield sites. Phytoremediation has several methodologies which includes
1. Phytoextraction or phytoconcentration : contaminant concentrated in roots, stem and foliage of plan.
2. Phytodegradation: plant enzymes help catalyze breakdown of the contaminant molecule.
3. Rhizosphere biodegradation: plant roots release nutrients to mircro-organisms which are active in
bio-degradation of the contaminant molecule.
4. Volatilization : transpiration of organics, selenium and mercury run through leaves of the plant
5. Stabilization: ant converts the contaminant into a form which is not bioavailable, or the plant prevents the spreading of a contaminant plume.
Applications of Phytoremediation
• The principal application of Phytoremediation is for lightly contaminated soils, sledges and waters where the material to be treated is at a shallow or medium depth and the area to be treated is large, so that agronomic techniques are economical and applicable for both planting and harvesting.
• Phytoremediation can be applied for producing energy from controlled combustion of harvested biomass
• Applied for harvesting valuable metals that are dispersed in soil
• Applied for providing quick remediation of Brownfield sites.