Skip Ribbon Commands
Skip to main content

Urban carbon sequestration​​

See Photos, Videos And Publications

Investigators: Erik Velasco

Description: A comprehensive climate change mitigation plan at city scale needs to consider the greenery's potential to offset carbon emissions.

​​​​​​​​​​​​​​​​​​​​​​​​​​Urban carbon sequestration​​

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​CENSAM stopped activities on Dec. 2017. For updates and information contact to Erik Velasco (

Many cities are developing policies to promote greenery as a measure to reduce their net greenhouse gas emissions. However, the potential to directly remove carbon dioxide (CO2) from the atmosphere by urban vegetation is still poorly supported by scientific evidence. Current assessments consider only the carbon accumulated by trees and usually neglect the contribution from soil respiration and the emissions associated with greenery management. Studies in mid-latitude cities suggest that the carbon uptake by urban vegetation is small compared to the magnitude of the anthropogenic emissions.

To investigate if the typically evergreen vegetation in (sub)tropical cities has a larger potential for carbon sequestration, we use CO2 flux data collected by eddy covariance (i.e. flux towers) and bottom-up estimations of CO2 emissions by anthropogenic sources to derive the biogenic contribution. We also conduct tree surveys and apply allometric equations and growth prediction models to estimate the annual carbon sequestration. More recently, we included measurements of below-ground CO2 production and started collecting samples of turfgrass clippings for carbon content analysis to evaluate the carbon exchange in a representative urban lawn.

Our results based on data from two residential neighborhoods of Singapore and Mexico City suggest that (sub)tropical vegetation may act as either an emission source or sink depending on the species and characteristics of the trees and the amount and conditions of pervious surfaces for soil respiration.

Lead researcher
- Erik Velasco (SMART, Singapore;
Alan Ziegler (NUS-Geography, Singapore)

- Elvagris Segovia (NUS-Geography, Singapore)
- Benjamin Lim (NUS-Biological Sciences, Singapore)
- Amy Choong Mei Fun (NUS-Biological Sciences, Singapore)
- Matthias Roth (NUS-Geography, Singapore)
- Luisa T. Molina (MCE2, USA)
- Rodrigo Vargas (Univ. of Delaware, USA)


​​ ​

bioenic CO2 flux.jpgCO2 flux contributions TK Sing.jpg 


​​ Videos
Singapore has the world's tallest vertical garden. Vertical greenery is
becoming an architectonic trend under the idea that it helps to
reduce  air pollution. But does it really work?
The Swedish National Public Television (SVT) visited Singapore and
talked with Erik Velasco, expert on air pollution and climate change.​

Photo Gallery Upload
Publications Upload

Back to Top