Archive · 12 Dec 2025
Delhi's toxic air harms trees, reduces oxygen production: DU study
A study by Delhi University found that the city's polluted air is harming trees.
The researchers looked at ten common tree species in Delhi and found that winter pollution is especially bad.
It makes leaves thinner, reduces their water content, and lowers chlorophyll levels.
Chlorophyll is important because it helps trees make oxygen.
The study found that some trees, like Amaltas and Bargad, can handle pollution better, while others, like Saptparni and Bael, are more sensitive.
The researchers also found that pollution makes leaves more acidic and increases a stress chemical called proline.
This shows that pollution is making it harder for trees to stay healthy and produce oxygen.
Delhi's toxic air reduces chlorophyll levels in trees, impacting oxygen production.
Winter pollution has a more adverse effect than monsoon, making leaves thinner and reducing water content.
Amaltas and Bargad are the most pollution-tolerant trees, while Saptparni and Bael are the most sensitive.
Pollution increases proline levels and makes leaves more acidic, indicating stress and altered metabolism.
Leaf thickness and dry matter content vary among species, with some trees better able to withstand pollution.
- Who
- Researchers at Delhi University's Acharya Narendra Dev College
- What
- Conducted a study on the impact of Delhi's air pollution on tree species
- When
- Leaf samples collected during monsoon (August-September) and winter (November-December) 2023
- Where
- Four zones in Delhi: Ashram, Tughlaqabad, Dwarka, Kamla Nehru Ridge
- Why
- To understand how air pollution affects tree health and oxygen production
- Study Title
- Seasonal variation of biochemical and morphological traits of selected tree species in polluted urban areas of Delhi City
- Study Zones
- Ashram (polluted road), Tughlaqabad (industrial), Dwarka (moderately polluted residential), Kamla Nehru Ridge (least polluted)
- Tree Species Studied
- Bael, Saptparni, Neem, Amaltas, Bargad, Pipal, Pilkhan, Mango, Champa, Jamun
- Study Period
- Monsoon (August-September) and Winter (November-December) 2023
- Key Findings
- Winter pollution reduces chlorophyll, increases proline, makes leaves thinner, lowers water content
- Most Pollution Tolerant
- Amaltas, Bargad
- Most Pollution Sensitive
- Saptparni, Bael
- Moderately Tolerant
- Mango, Champa, Pilkhan, Jamun