Summary: Four researchers in Italy and one in Russia consider phytoremediating street tree species for combating heavy metals, stormwater runoff and traffic noise.
Silver birch (Betula pendula) joins eight tree species -- black locust (Robinia pseudoacacia), English oak (Quercus robur), European hornbeam (Carpinus betulus), littleleaf linden lime tree (Tilia cordata), London plane (Platanus x hispanica), maidenhair tree (Ginkgo biloba), sycamore (Acer pseudoplatanus) and tree of heaven (Ailanthus altissima) -- in a list of nine best central European phytoremediators; Betula pendula in Inari wilderness, Northern Lapland, northeastern Finland; Monday, July 31, 2006, 18:55: Percita at Flickr, CC BY SA 2.0 Generic, via Wikimedia Commons |
Phytoremediating street tree species assist urban ecosystems with air purification, carbon sequestration and storage, microclimate improvement, noise reduction and runoff mitigation, according to an article for Arboriculture & Urban Forestry July 2017.
Tree bark, leaves and roots bring in contaminants that bind to acid aerosols, carbonaceous core-adsorbed or core-attached metals, hydrocarbons and organic compounds in airborne particulate matter. Airborne particulate matter and such related matrices as river sediment, road dust, soils and vegetation contain traffic-related elements (TREs) that constitute risk factors for human health. Bioindicating informants about environmental quality and phytoremediating accumulators of TREs beyond nutrient requirements demonstrate "applied aspects of the uptake of chemical elements from soil to plants."
Environmental quality improvement and maintenance encourage urban planners to emphasize bioindication and phytoremediation potential and stress tolerance in tree selections for heavy-traffic roads and urban-industrial areas.
Claudia Dadea, Tanja Mimmo, Massimo Tagliavini and Stefan Zerbe in Bolzano, Italy, and Alessio Russo in Vladivostok, Russia, find nine central European tree species as candidates.
Disturbed surfaces, extensive costs and intensive labor get in the way of conventional remediation by chemicals, containment, isolation of mechanical/pyrometallurgical separation of polluted, salinized, unsustainable lands. Phytoremediation, as plant-mediated phytoextraction, contrastingly has metal-accumulating plants disposed of or incinerated after these hyperaccumulators head heavy metals from the soil into the plants' "harvestable parts." Phytoremediating phytostabilization involves metal-tolerant plants immobilizing and inactivating metals through "in situ rhizospheric processes" of complexation (combination) and sorption (attachment) to impede air and groundwater contamination.
Metal-tolerant, phytoremediating street tree species juggle development of deep, dense roots in metal-specific, nutrient-poor, select natural habitats and translocation of trace elements to leaves and shoots.
Deep, dense root systems, high transpiration and large total leaf area keep urban street trees efficient absorbers, accumulators and transformers of contaminated brownfields and polluted landfills.
Review of 134-plus dendrology, tree biology-, tree identification-related sources lead four Free University of Bozen-Bolzano-based researchers and one Far Eastern Federal University-based researcher to nine species. They mention Acer pseudoplatanus, Ailanthus altissima, Carpinus betulus, Ginkgo biloba, Platanus x hispanica, Quercus robur and Tilia cordata with fast-growing, low-cost Betula pendula and Robinia pseudoacacia. They note the bioindicating, phytoremediating potentials of heavy metal- and xenobiotic- (foreign chemical substance-) tolerant salt-loving plants and of highly disease- and pest-tolerant deciduous tree species.
Coarse-, hairy-, resinous-, scaly-surfaced foliar and mycorrhizal fungi-friendly root trapping optimizes the potentially phytoremediating street tree species Tilia cordata's and Betula pendula's contaminant and particulate interceptions.
Ecosystem-greening services place in urban areas trees with emissions of pollen and of biogenic volatile organic compounds that anthropogenic source-released compounds provoke into producing air pollution.
Intrinsic hardiness and stress tolerance qualify all nine street-planted species as potential ecosystem service providers that bioindicate, biomonitor, phytoextract and phytostabilize heavy metals and other pollutants. Intrinsic bioindication capacities and drought, pathogen, pest, salt and temperature stress tolerances reap urban planning-related rewards from even species that release pollen and restrict air flow. The five researchers suggest starting large-scale municipal ecosystem restoration projects to see whether green infrastructure supports human health and urban air, climate, soil and water quality.
Heavy metals task nine commonly planted, potentially phytoremediating street tree species with tendering oxygen, tethering runoff, throttling noise, thwarting pollution and tweaking human happiness and health.
Acknowledgment
My special thanks to:
talented artists and photographers/concerned organizations who make their fine images available on the internet;
University of Illinois at Urbana-Champaign for superior on-campus and on-line resources.
Image credits:
talented artists and photographers/concerned organizations who make their fine images available on the internet;
University of Illinois at Urbana-Champaign for superior on-campus and on-line resources.
Image credits:
Silver birch (Betula pendula) joins eight tree species -- black locust (Robinia pseudoacacia), English oak (Quercus robur), European hornbeam (Carpinus betulus), littleleaf linden lime tree (Tilia cordata), London plane (Platanus x hispanica), maidenhair tree (Ginkgo biloba), sycamore (Acer pseudoplatanus) and tree of heaven (Ailanthus altissima) -- in a list of nine best central European phytoremediators; Betula pendula in Inari wilderness, Northern Lapland, northeastern Finland; Monday, July 31, 2006, 18:55: Percita at Flickr, CC BY SA 2.0 Generic, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Betula_pendula_Finland.jpg
Robinia pseudoacacia in Priverno, Latina province, Lazio region, central Italy; Sunday, June 14, 2009, 14:40: Fontema, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Robinia_Priverno.JPG
For further information:
For further information:
Dadea, Claudia; Russo, Alessio; Tagliavini, Massimo; Mimmo, Tanja; and Zerbe, Stefan. July 2017. "Tree Species as Tools for Biomonitoring and Phytoremediation in Urban Environments: A Review with Special Regard to Heavy Metals." Arboriculture & Urban Forestry 43(4): 155-167.
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Available @ https://earth-and-space-news.blogspot.com/2014/02/tree-twig-anatomy-ecosystem-stress.html
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Available @ https://earth-and-space-news.blogspot.com/2013/12/community-and-tree-safety-awareness.html
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Available @ https://earth-and-space-news.blogspot.com/2013/10/chain-saw-gear-and-tree-work-related.html
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Available @ https://earth-and-space-news.blogspot.com/2013/10/storm-damaged-tree-clearances-matched.html
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Available @ https://earth-and-space-news.blogspot.com/2013/08/storm-induced-tree-damage-assessments.html
Available @ https://earth-and-space-news.blogspot.com/2013/08/storm-induced-tree-damage-assessments.html
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Available @ https://earth-and-space-news.blogspot.com/2013/06/storm-induced-tree-failures-from-heavy.html
Available @ https://earth-and-space-news.blogspot.com/2013/06/storm-induced-tree-failures-from-heavy.html
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Available @ https://earth-and-space-news.blogspot.com/2013/04/urban-tree-root-management-concerns.html
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Available @ https://earth-and-space-news.blogspot.com/2012/12/healthy-urban-tree-root-crown-balances.html
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Available @ https://earth-and-space-news.blogspot.com/2012/10/tree-adaptive-growth-tree-risk.html
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Available @ https://earth-and-space-news.blogspot.com/2012/08/tree-risk-assessment-mitigation-reports.html
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Available @ https://earth-and-space-news.blogspot.com/2012/06/internally-stressed-response-growing.html
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Available @ https://earth-and-space-news.blogspot.com/2012/04/three-tree-risk-assessment-levels.html
Available @ https://earth-and-space-news.blogspot.com/2012/04/three-tree-risk-assessment-levels.html
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Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment-risk.html
Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment-risk.html
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Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment.html
Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment.html
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Available @ https://earth-and-space-news.blogspot.com/2011/12/tree-risk-assessment-tree-failures-from.html
Available @ https://earth-and-space-news.blogspot.com/2011/12/tree-risk-assessment-tree-failures-from.html
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Available @ https://earth-and-space-news.blogspot.com/2011/10/five-tree-felling-plan-steps-for.html
Available @ https://earth-and-space-news.blogspot.com/2011/10/five-tree-felling-plan-steps-for.html
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Available @ https://earth-and-space-news.blogspot.com/2011/08/natives-and-non-natives-as-successfully.html
Available @ https://earth-and-space-news.blogspot.com/2011/08/natives-and-non-natives-as-successfully.html
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Available @ https://earth-and-space-news.blogspot.com/2011/06/tree-ring-patterns-for-ecosystem-ages.html
Available @ https://earth-and-space-news.blogspot.com/2011/06/tree-ring-patterns-for-ecosystem-ages.html
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Available @ https://earth-and-space-news.blogspot.com/2011/04/benignly-ugly-tree-disorders-oak-galls.html
Available @ https://earth-and-space-news.blogspot.com/2011/04/benignly-ugly-tree-disorders-oak-galls.html
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Available @ https://earth-and-space-news.blogspot.com/2011/02/tree-load-can-turn-tree-health-into.html
Available @ https://earth-and-space-news.blogspot.com/2011/02/tree-load-can-turn-tree-health-into.html
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Available @ https://earth-and-space-news.blogspot.com/2010/12/tree-electrical-safety-knowledge.html
Available @ https://earth-and-space-news.blogspot.com/2010/12/tree-electrical-safety-knowledge.html
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