Q.Define - 'Bioremediation'.

Bioremediation is the use of microorganisms or plants to clean up environmental pollution, treating wastewater, industrial waste and solid waste and removing oil, petrochemical residues, pesticides or heavy metals from soil or groundwater - typically cheaper, more sustainable and more effective at low contaminant concentrations than physical or chemical remediation. Named strategies include phytoremediation (plants), mycoremediation (fungi), bioventing (boosting oxygen/air flow to accelerate degradation), bioleaching (recovering metals via microorganisms in solution), bioaugmentation (adding microbes to speed degradation), composting (converting solid waste to manure via microbes), rhizofiltration (metal uptake/organic-compound degradation by rhizosphere microbes) and rhizostimulation (improving plant growth conditions in the rhizosphere). Its real limits: only biodegradable contaminants can be treated this way, each process must be tailored to the specific site's conditions, and small-scale pilot testing is needed before full deployment. …