TY - JOUR
T1 - Investigating carbonate formation in urban soils as a method for capture and storage of atmospheric carbon
AU - Washbourne, C.-L.
AU - Renforth, Phil
AU - Manning, D. A. C.
PY - 2012/8/1
Y1 - 2012/8/1
N2 - This paper investigates the potential for engineered urban soils to
capture and store atmospheric carbon (C). Calcium (Ca) and magnesium
(Mg) bearing waste silicate minerals within the soil environment can
capture and store atmospheric C through the process of weathering and
secondary carbonate mineral precipitation. Anthropogenic soils, known to
contain substantial quantities of Ca and Mg-rich minerals derived from
demolition activity (particularly cement and concrete), were
systematically sampled at the surface across a 10 ha brownfield site,
Science Central, located in the urban centre of Newcastle upon Tyne,
U.K. Subsequent analysis yielded average carbonate contents of 21.8 ± 4.7% wt CaCO3. Isotopic analysis demonstrated δ18O values between − 9.4‰ and − 13.3‰ and δ13C values between − 7.4‰ and − 13.6‰ (relative to Pee Dee Belemnite), suggesting that up to 39.4 ± 8.8% of the carbonate C has been captured from the atmosphere through hydroxylation of dissolved CO2 in high pH solutions. The remaining carbonate C is derived from lithogenic sources. 37.4 kg of atmospheric CO2 has already been captured and stored as carbonate per Mg of soil across the site, representing a carbon dioxide (CO2) removal rate of 12.5 kgCO2 Mg− 1 yr− 1. There is the potential for capture and storage of a further 27.3 kgCO2 Mg− 1
in residual reactive materials, which may be exploited through
increased residence time (additional in situ weathering). Overall, the
Science Central site has the potential to capture and store a total of
64,800 Mg CO2 as carbonate minerals. This study illustrates
the potential for managing urban soils as tools of C capture and
storage, an important ecosystem service, and demonstrates the importance
of studying C storage in engineering urban anthropogenic soils.
AB - This paper investigates the potential for engineered urban soils to
capture and store atmospheric carbon (C). Calcium (Ca) and magnesium
(Mg) bearing waste silicate minerals within the soil environment can
capture and store atmospheric C through the process of weathering and
secondary carbonate mineral precipitation. Anthropogenic soils, known to
contain substantial quantities of Ca and Mg-rich minerals derived from
demolition activity (particularly cement and concrete), were
systematically sampled at the surface across a 10 ha brownfield site,
Science Central, located in the urban centre of Newcastle upon Tyne,
U.K. Subsequent analysis yielded average carbonate contents of 21.8 ± 4.7% wt CaCO3. Isotopic analysis demonstrated δ18O values between − 9.4‰ and − 13.3‰ and δ13C values between − 7.4‰ and − 13.6‰ (relative to Pee Dee Belemnite), suggesting that up to 39.4 ± 8.8% of the carbonate C has been captured from the atmosphere through hydroxylation of dissolved CO2 in high pH solutions. The remaining carbonate C is derived from lithogenic sources. 37.4 kg of atmospheric CO2 has already been captured and stored as carbonate per Mg of soil across the site, representing a carbon dioxide (CO2) removal rate of 12.5 kgCO2 Mg− 1 yr− 1. There is the potential for capture and storage of a further 27.3 kgCO2 Mg− 1
in residual reactive materials, which may be exploited through
increased residence time (additional in situ weathering). Overall, the
Science Central site has the potential to capture and store a total of
64,800 Mg CO2 as carbonate minerals. This study illustrates
the potential for managing urban soils as tools of C capture and
storage, an important ecosystem service, and demonstrates the importance
of studying C storage in engineering urban anthropogenic soils.
U2 - 10.1016/j.scitotenv.2012.05.037
DO - 10.1016/j.scitotenv.2012.05.037
M3 - Article
SN - 0048-9697
VL - 431
SP - 166
EP - 175
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -