Biodiversity Overview
- Biodiversity refers to the variety and variability of all living organisms on Earth.
- It is crucial for human well-being, a healthy planet, and economic prosperity.
- Currently, 25% of all species face the threat of extinction.
International Day for Biological Diversity
- Observed annually on May 22.
- Theme (2025): “Harmony with nature and sustainable development”.
- Commemorates the adoption of the Convention on Biological Diversity (CBD) on May 22, 1992.
Kunming-Montreal Global Biodiversity Framework (GBF)
- Developed by the CBD.
- 4 Goals and 23 Targets to be achieved by 2030.
- Key Targets:
- Conserve and manage 30% of terrestrial and marine biodiversity.
- Target 12: Enhance green and blue spaces in urban areas.
- Aligns with UN SDG Goal 11: Make cities safe, resilient and sustainable.
Importance of Urban Biodiversity
Health Benefits
- Trees provide food, water, fibre, reduce urban heat island effect, and aid flood control.
- Help in pollution abatement, carbon sequestration, and temperature control.
- Green belts can reduce:
- Noise by 5 decibels.
- Temperature by 3.5°C (Frankfurt example).
- Increase humidity by 5%.
- Offer recreational, spiritual, and mental health benefits.
Economic Benefits
- Urban trees offer annual services worth $967,000 (₹8 crore) per sq. km (Prof. Theodore Endreny).
- Urban greenery boosts:
- Local economy.
- Job creation.
- Real estate value.
- Tourism and ecological services.
Current Urban Green Cover Status (Forest Survey of India)
- Average urban forest cover: 10.26%.
- Examples:
- Mumbai: 25.43%.
- New Delhi, Hyderabad: 12.6%.
- Forest cover loss (2021–2023):
- Chennai: 2.6 sq. km.
- Hyderabad: 1.6 sq. km.
Strategies & Initiatives for Urban Biodiversity
Urban Planning and Green Infrastructure
- UN Habitat 3-30-300 Rule:
- 3 trees visible from every home, school, workplace.
- 30% tree canopy cover in each neighbourhood.
- Public green space within 300 metres of every residence.
City Biodiversity Index
- Prepared using:
- Native biodiversity extent.
- Ecosystem services provided.
- Level of governance.
- ICLEI Asia has prepared indices for cities like Kochi, Gangtok, Nagpur.
- Local Biodiversity Strategy and Action Plans (LBSAP) are formulated post-assessment.
Successful Models and Case Studies
Chennai’s Urban Greening
- Koyambedu Market Greening (2021):
- Natural regeneration of 141 plant species, 35 bird and 27 butterfly species.
- Mimics three-layered forest, better than Miyawaki model.
- Million Tree Plantation Strategy (2018): Aimed to plant 1 million native trees in 5 years.
- Guindy Race Course: Transformed into a lake to boost groundwater recharge.
- Pallikaranai Marsh: Partially restored, declared a Reserved Forest (Ramsar site).
Key Issues & Solutions
Challenges
- Unplanned urban development, encroachments, and pollution.
- Loss of home garden trees due to high-rise buildings.
- Disappearance of urban water bodies due to dumping and untreated sewage.
Recommendations
- Mandatory tree planting for plots > 2400 sq. ft. (at least 5 trees).
- Promote roof gardens and kitchen gardens for medicinal plants and herbs.
- Legal protection and ecological restoration of urban water bodies.
- Promote decentralized greening through RWAs, NGOs, corporates.
Urban areas have the resilience to support biodiversity, provided enabling environments are created. Cities must:
- Integrate biodiversity goals in planning.
- Ensure community participation.
- Achieve a balance between development and sustainability.
