Urban carbon sequestration
CENSAM stopped activities on Dec. 2017. For updates and information contact to Erik Velasco (firstname.lastname@example.org).
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.
Does urban vegetation enhance carbon sequestration?
POSTER, Erik Velasco et al., ICUC-9, 2015.
CO2 sequestration by urban vegetation at neighbourhood scale in tropical cities
TALK, Erik Velasco et al., AGU-2013.
How much CO2 does vegetation capture in tropical cities? Case study of a residential neighbourhood in Singapore
POSTER, Erik Velasco et al., AGU-2012.
Soil characteristics and their influences on CO2 efflux in a tropical urban lawn