Grete Gansauer

BZ 572

November 29, 2012

Trees in Phytoremediation

Outline

Why trees make good phytoremediators

Species currently used in phytoremediation

Pollutant clean up and methods

Organic Remediation

Inorganic Remediation

Some Case Studies

Capturing Economic Value from projects

Why trees are awesome

They *can* grow fast

And use a lot of water (high transpiration

rates)

They are large

Their root systems are also large and deep

Large, microbially diverse rhizosphere

Potential for ecological restoration

They are woody

They grow in bad places

They are perennials

Their products have economic value

Tree species used for remediation

Poplar

Willow

Genipa americana

Mulberry

Legumes

Eucalyptus

Evergreens?

Riparian tree species are

common

High transpiration and

water uptake rates

Fastest growers

Clean up pollution in water

Not used for merchantable

timber

Species of Acacia accumulate Cadmium

Ornamental Mulberry

Methods of Tree-remediation

Stabilization

Rhizofiltration*

Riparian Buffer Strips

Extraction*

Volatilization*

Stimulation

Degradation

Detoxification

Riparian Buffer Strip in Wisconsin

Historical and Current Uses of Trees in

Phytoremdiation

Use of trees in Phytoremediation since the early 1990’s

Organic pollutant clean up:

TCE, TNT, PAH, MTBE

Inorganic pollutant clean up:

Cr, Cd, Pb, Zn

Phytoremediation in conjunction

with Biomass Fuels production

Willow being grown on contaminated

land for biomass production

Trees and Organic Remediation

TCE

Poplar volatilization, stabilization, stimulation

Naphthalene

Eucalyptus rhizodegradation

MTBE

Poplar hybrids

Pines

PAH

Mulberry

Using Eucalyptus to remediate Naphthalene

Trees and Metal Remediation

Potential for accumulation & phytoextraction

Cadmium

Willow

Legumes (Acacia, Mimosa, Anadenantera)

Genipa americana

Lead

Eucalyptus

Legumes

Mangrove

Chromium

Genipa americana

Genipa americana and Cr

South American Rainforest Species

Phytostabilization and Rhizofiltration of two

harmful Cr ions

Rhizofiltration of Cr3+ on roots

Phytostabilization of Cr6+

Cr6+ converted to Cr3+ in plant

Adsorbed Cr on roots, but did

not translocate Cr to the shoot

Cr lowered PS rate

Lower K concentration in leaves w/ Cr

Riparian Buffer potential?

Rhizofiltration of Zn and Cd as well

Genipa americana

Chromium in action

Meanwhile, in Europe… Phytoextraction and Biomass Fuels

Production

Short-Rotation Coppice Willow plantations

Biomass plantations on former agricultural

land (contaminated?)

Irrigated with waste water

Willow coppice regeneration.

Trees are harvested every 3-5 years

Willows being irrigated with industrial wastewater

Phytoextraction with Salix viminalis Concentration of Cd in willow-planted

soil was 12% lower than control soil (field study)

Willow-planted soils had “significantly higher Carbon”

Microbial stimulation potential?

Negligible difference in soil pH

Willows in alkaline soils accumulated the most Cd

High irrigation rates…even with waste water!

High accumulation of Zn and Cd in willow leaves

Removed 5% Zn and 20% Cd from the soil (greenhouse study)

Willows planted on former

agricultural land near a

wastewater treatment plant.

Biomass Biproducts

Metals accumulated in

shoot, shoot harvested

for fuel

Burned in a Fluidized

Bed Reactor

Metals not combusted,

still found in ash

Don’t re-scatter

contaminated ashes on-

site for fertilizer!

Questions!

What are two reasons that trees good candidates for

phytoremediation?

Name one Tree species I mentioned and how it can be used

for phytoremediation.

References 1. Arnold, C.W. 2007. Phytovolatilization of oxygenatied compounds from gasoline-impacted groundwater at an underground storage tank site via conifers.

International Journal of Phytoremediation. Vol. 9, iss. 1. pp. 53-69.

2. Aronsson, P. & Perttu, K. 2001. Willow vegetation filters for wastewater treatment and soil remediation combined with biomass production. Forestry Chronicle,

Vol. 77 iss. 2. pp 293–299

3. Barbosa, Rena Mirian T. et al. 2007. A physiological analysis of Genipa americana: a potenital phytoremediator tree for chromium-polluted watersheds.

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4. Burken, J.G. 1996. Hybrid poplar tree phytoremediation of volatile organic compounds. Americal Chemical Society. Vol. 212. pp. 106-110.

5. Dimitriou and Ioannis et al. 2012. Changes in organic carbon and trace elements in the soil of willow short-rotation coppice plantations. Bioenergy Res. Vol. 5.

pp 563-572.

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137.

8. Ma, X.X. 2004. Phytoremediation of MTBE with hybrid poplar trees. International Journal of Phytoremediation Vol 6., iss. 2. pp 157-167.

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Studies. Vol. 67, iss. 5. pp. 1515-1520.

10. Pereira, A.C.C. 2012. Heavy metals concentration in tree species used for revegetation of contaminated area”. Revista Ciencia Agronomica. Vol.

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11. Santana, Kaline B. et al. 2012. Physiological analyses of Genipa americana reveals a tree with ability as phytostabilizer and rhizofilter of chromium ions for

phytoremediation of polluted watersheds. Environmental and Experimental Botany. Vol. 80. pp 35-42.

12. Souza, V.L. et. al. 2010. Morphophysiological responses and programmed cell death induced by cadmium in Genipa americana (Rubiaceae). Biometals. Vol. 24. pp:

59-71

13. Stomp, A.M. et al. 1993. Genetic improvement of tree species for remediation of hazardous wastes. Tissue Culture Association, In Vitro Cell Division of

Biology. Vol. 29. pp 227-232.

14. Syc, Michael et al. 2012. Willow trees from heavy metals phytoextraction as energy crops. Academy of Sciences of Czech Republic Journal of Biomass and

Bioenergy. Vol. 37. pp 106-113.

15. Xingmao, M. et al. 2004. Phytoremediation of MTBE with hybrid poplar trees. International Journal of Phytoremediation. Vol. 6, iss. 2. pp 157-167