Guidelines suistainable urban forestry ROMA_Eng

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ESTIMATE REFERENCE
Carbon sequestration by urban forest estimated in few
hundreds Kg of carbon for hectare for year (various USA
cities)
Nowak D.J. and D.E. Crane, 2002. Carbon
storage and sequestration by urban trees in the
USA. Environmental Pollution, 116: 381-389.
MillionTreesNYC Project, which expects to plant one
million of trees in the city of New York, with a direct
carbon storage estimated in more than 1500 t/year
Morani A. et al., 2010. How to select the best
tree planting locations to enhance air pollution
removal in the MillionTreesNYC initiative.
Environmental Pollution 159:1040-1047.
Carbon sequestration between 17 t/ha (areas with high tree
density) and 1 t/ha (areas with scarce arboreal cover)
(various residential areas in Liverpool)
Whitford, V., et al., 2001. City form and
natural process—indicators for the ecological
performance on urban areas and their
application to Merseyside, UK . Landscape
Urban Planning. 57: 91–103.
Greenhouse gases absorption by the 28,43 Km2 of green
areas, trees and shrubs inside the administrative boundary of
the city of Barcellona estimates in about 4 millions t/year of
CO2 eq.
F. Baró, L. Chaparro, E. Gómez-Baggethun, J.
Langemeyer, D. J. Nowak , J. Terradas, 2014.
Contribution of Ecosystem Services to Air
Quality and Climate Change Mitigation
Policies: The Case of Urban Forests in
Barcelona, Spain. In AMBIO A Journal of the
Human Environment. 43: 466-479.
Estimates (obtained with different methodologies) of 160
t/year of CO2 sequestered by trees in the Parco Ducale
(Bologna); 54 t/year of carbon for trees in Villa Borghese
(Roma)
Calfapietra C. et al., 2011. La foresta urbana
per l’abbattimento di CO2. CNR and
Università di Firenze.
Carbon sequestration by trees inside the Grande Raccordo
Anulare (Roma) estimates in more than 2000 t/year
Attorre, F., and Bruno, F.,2010. Servizi
ecologici e valore economico degli spazi verdi
urbani. In “La gestione della natura negli
ambienti urbani”. Edited by WWF and
MATTM: 170-178.
Referring to the project Life+ GAIA (Green Areas Inner-city Agreement) in the Municipality of
Bologn , the Biometeorology Institute (Ibimet) of CNR of Firenze estimated carbon sequestration by
24 species suitable to be planted in urban environment, on the basis of scientific knowledge and of the
recommendations provided by the Municipality. For example for the little-leaf linden (Tilia cordata) a
quantity of CO2 stored of 3.660 Kg in 30 years in the city and of 5.070 Kg in 50 years in a green area
was estimated; for the field mapple (Acer campestre) and for the Norway mapple (A. platanoides)
respectively a quantity of 2.490 Kg and 4.807 Kg in 30 years in the city and of 3.400 Kg and 6.601 Kg
in 50 years in a green area; for the Turkey oak (Quercus cerris) a quantity of 4.000 Kg in 30 years in
the city and of 5.500 Kg in 50 years in a green are .
Also small green areas, if conveniently planned and managed, are able to reduce indirectly CO2
emissions, through the mitigation of temperature range, both in winter and in summer, thanks to a less
use of air conditioning and heating. Therefore, with a careful urban redesign, also courtyards could
represent an easy and cheap solution for improving citizen wellbein .
In particular, studies carried on by the Biometeorology Institute (Ibimet) of CNR of Firenze, have
demonstrated that vegetated areas have a cooling effect which increases, more or less in a linear way,
with their dimensions; thus they have a great value for summer temperatures mitigatio
1.1.2 Pollutants abatement
Atmospheric pollution represents one of the main environmental threats in urban areas.
Specifically, particulate matter (PM10 e PM2.5), nitrogen dioxide (NOx) and ozone (O3) are the most
important atmospheric pollutants in urban areas. Vegetation contributes to pollutants removal (NOx,
5
6 For estimates of all 24 species see
7 See, for example “Cortili verdi per combattere afa e gelo”. By Press Office of CNR.
8 See, for example “Cortili verdi per combattere afa e gelo”. By Press Office of CNR