ENVS10011 Lecture Notes - Lecture 12: Hyperaccumulator, Phytoremediation, Brassica Juncea
17 May 2018
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WEEK 12: PHYTOREMEDIATION
Bioremediation
“using organisms to clean up pollution”
• Mostly organo-chemicals (eg. Herbicides + pesticides, oil spills)
• Occurs to some extent naturally (at vegetated, polluted sites)
o Some have adapted to certain chemicals in environment
Phytoremediation:
“using plants to clean up
• Used less, harder to transfer to sites
• Hard when wanting to clean an element, rather than a compound (can’t get rid of –
only transfer into different forms)
• 10 fold cheaper than engineering solutions – uses plants, no energy input, in situ
• Technologies developed for remediating water (constructed wetlands), soil + air
• EXAMPLE: cabbage plantation grown next to zinc smelter in Poland
o Lead concentration built up in soil, cabbage extracts from soil
Phytomining: using plants to extract minerals
• Alyssium murale: accumulates nickel preferentially (hyperaccumulation), very tolerant,
used near mining sites
• Less destructive, paddock of plants instead of digging holes in ground
Selenium
• Necessary trace element for organisms (including humans) in low concentrations
• Mainly found in water, then enters soil and also found in natural rock formations,
released when rocks are disturbed (erosion, mining)
• Australia: low in soils, therefore low in grains (food)
• California: higher levels in bedrock + water, bring water to evaporate, salts
concentrated in dry pond, wind blows around + enters waterway – results in
deformation of offspring (animals + humans)
• Indian Mustard: a selenium hyperaccumulator, phytovolatilisation
Phytostimulation: only works for
compounds, stimulate reactions that
degrade compounds (not elements)
Phytostabilisation: toxic elements,
change to a stable form
Phytoextraction: when they remove
pollutant from the soil by taking it up
- Element: accumulates in plant,
easier to deal with – can kill
plant
Phytovolatilisation: transformation of
form of pollutant in plants, so can be
released in atmosphere
Phytodegradation: when a plant
degrades pollutant that is stored in
plant after taking up from soil
Document Summary
Using organisms to clean up pollution : mostly organo-chemicals (eg. herbicides + pesticides, oil spills, occurs to some extent naturally (at vegetated, polluted sites, some have adapted to certain chemicals in environment. Phytostimulation: only works for compounds, stimulate reactions that degrade compounds (not elements) Phytostabilisation: toxic elements, change to a stable form. Phytoextraction: when they remove pollutant from the soil by taking it up. Element: accumulates in plant, easier to deal with can kill plant. Phytovolatilisation: transformation of form of pollutant in plants, so can be released in atmosphere. Phytodegradation: when a plant degrades pollutant that is stored in plant after taking up from soil. Phytomining: using plants to extract minerals: alyssium murale: accumulates nickel preferentially (hyperaccumulation), very tolerant, used near mining sites, less destructive, paddock of plants instead of digging holes in ground.
