Urban tree carbon density and CO2 equivalent of National Zoological Park, Delhi

Abstract

In a highly urbanized city like Delhi, the urban forest plays a vital role in climate change mitigation by capturing and storing carbon dioxide (CO₂) from the atmosphere. Urban vegetation helps in increasing carbon sink and CO₂ equivalent (CO₂eq) and also provides other aesthetic and psychological environmental benefits. To understand how urban trees are vital for carbon sink, the present study aimed to quantify the carbon density and CO₂eq in trees at National Zoological Park (NZP), New Delhi, a tropical semi-arid region of India. For this, we estimated tree biomass or dry matter content of 25 species with the help of allometric equations which are available in published literature and applicable for the tropical region. It was observed that the highest diameter at breast height (DBH) was contributed by Ficus sp. while the maximum density among adult tree species found in Albizia procera. The total mean dry matter content, C density, and CO₂eq of NZP were 92.10 Mg ha^-1, 43.61 Mg-C ha^-1, and 168.83 Mg ha^-1, respectively. The highest biomass, C density, and CO₂eq obtained in the species of Ficus benghalensis followed by Ficus racemosa and Azadirachta indica. The data indicates that the trees having the capacity to store carbon are essential for the maintenance of a sustainable environment. Thus, the study suggests that there is a substantial scope to increase the carbon density and CO_2eq in urban city through adopting various management strategies viz. afforestation and reforestation program on degraded and abandoned land to maintain a clean and sustainable environment.

Keywords: Carbon sequestration; Dry matter content; Green space; Tree biomass; Urban vegetation.