Carbon Sequestration Potential of Trees in Urban Vegetation Islands: A Case Study

Aim: Increasing levels of atmospheric carbon dioxide (CO2) and other “greenhouse” gases contribute to an increase in atmospheric temperature. Trees act as a sink for CO2 by fixing carbon during photosynthesis and storing excess carbon as biomass. The current study focuses on the contribution of vegetation within Janki Devi Bajaj Government Girls College, Kota towards carbon sequestration potential and climate regulation.

Study Design: Non-destructive method of biomass estimation was used to measure the GBH of individual trees on the campus.

Place and Duration: The study was conducted in Janki Devi Bajaj Government Girls College, Kota in Rajasthan, India from July 2022 to June 2023.

Methodology: Above-ground biomass (AGB) and below-ground biomass (BGB) were calculated with the help of field measures of diameter at breast height (DBH) of the trees using allometric equations and Carbon equivalent was calculated with scientifically verified formula.

Results: The present study enumerated a total of 849 trees belonging to 43 tree species on the campus. The most dominant species was Syzygium cumini (L.) Skeels with a total of 163 trees followed by Phoenix sylvestris (L.) Roxb (121 trees) and Eucalyptus obliqua L'Her (97 trees). The above-ground biomass (AGB) and below-ground biomass (BGB) of all the trees on the campus are equivalent to 373937 kg and 56090.54 kg, respectively. The total biomass accumulated is 430027.5 kg and the total carbon content of the campus trees is equal to 215013.75 kg. The total carbon sequestered by all the trees in a year is 788.38 tons. In other words, on average carbon sequestered by an individual tree on the campus is 928.60 kg/year or 0.93 tons/year.

Conclusion: Urban green islands are likely to have a wider impact on biomass accumulation in turn carbon storage and sequestration in comparison to other structural parameters like species richness or density. Thus, in urban areas, the amount of potential carbon storage is positively influenced by increasing biomass.