Pune sees 34% decline in carbon sequestration as urban sprawl reduces green cover

Pune: The city has seen a 34% decline in its carbon sequestration capacity — the natural ability of life and ecosystems to store carbon — due to rapid urbanisation over the last decade, a recent study revealed.The study was conducted by Dr Pankaj Koparde of MIT-World Peace University (MIT-WPU), in collaboration with Pratiksha Chalke of Sustaina Greens LLP. The research, titled "Losing the Carbon Game? Changing Face of a Tropical Smart Metro City and its Repercussions on Carbon Sequestration, Heat and Flood Mitigation Capacity," was published in the journal Sustainable Futures in April 2025.The study also revealed that between 2013 and 2022, Pune's built-up areas expanded by 12%, leading to a substantial loss of green cover.This urban growth reduced the city's carbon absorption ability and weakened its flood mitigation potential by 13%.The study highlighted a reduction in water runoff retention potential within built-up areas, where human infrastructure expansion contributed to a notable decrease in the land's capacity to manage runoff. However, the capacity of the hills to manage runoff remained unaltered and at full capacity."The decline is largely attributed to the disruption of natural drainage systems and unregulated construction along riversides and floodplains. This, combined with continued landscape alterations, is likely to increase the city's vulnerability to floods, a growing concern given Pune's increasingly erratic monsoon patterns," said Koparde."Our results underline the irreplaceable role of native geological and ecological features such as urban hills and wetlands in maintaining urban environmental health. As tropical cities like Pune expand, sustainable development can only be achieved by leveraging these native assets rather than undermining them," he said.The study focussed on decadal changes in the ecosystem, such as carbon sequestration, flood mitigation, heat mitigation, and vegetation in Pune city from 2013 to 2022.The city lost around 34% of its carbon storage capacity within a decade, and it was pronounced in the hilly regions, especially at Taljai hill. "A decline in carbon storage potential could impact the city's ability to mitigate climate change effects and maintain a healthy urban ecosystem," revealed the study.Researchers provided suggestions, including afforestation, sustainable land management, enhanced vegetation around water bodies, and urban forest initiatives to increase the same.The city also saw an increase in built-up area from 30% in 2013 to 43% in 2022 — underscoring rapid urbanisation and loss of barren land.This barren land, due to its location at the junction of the Western Ghats biodiversity hotspot and Deccan Plateau, was a scrub-savanna vegetated space."Tagging scrub-savanna or grassland systems as barren lands and converting them into other land-use categories is exerting severe pressure on the unique biodiversity of the region and decreasing productivity. In the case of Pune city, the hills are at the stake of conservation, as they are in the midst of the city," stated the study.Heat mitigation was also observed mainly at the hills and less so at the built-up areas, indicating limited or no capacity to mitigate heat. "This observation underscores the integral role of natural green spaces, such as the hills, in ameliorating urban heat island effects while accentuating the challenges posed by urbanisation and human development in impeding effective heat mitigation strategies," the study showed.The research also highlighted that to enhance resilience to floods, it is crucial to preserve the existing riparian vegetation around the Mula-Mutha rivers. "This vegetation acts as a natural buffer, helping to stabilise riverbanks, reduce runoff, and improve water absorption," the researchers stated in the study.Koparde added, "We strongly advocate for urgent policy interventions including the protection and restoration of urban hills, wetlands, and riverside green buffers. Tools like ecosystem service valuation models and integrated urban planning frameworks must be adopted to ensure that future growth is ecologically balanced and informed by data."Pune: The city has seen a 34% decline in its carbon sequestration capacity — the natural ability of life and ecosystems to store carbon — due to rapid urbanisation over the last decade, a recent study revealed.The study was conducted by Dr Pankaj Koparde of MIT-World Peace University (MIT-WPU), in collaboration with Pratiksha Chalke of Sustaina Greens LLP. The research, titled "Losing the Carbon Game? Changing Face of a Tropical Smart Metro City and its Repercussions on Carbon Sequestration, Heat and Flood Mitigation Capacity," was published in the journal Sustainable Futures in April 2025.The study also revealed that between 2013 and 2022, Pune's built-up areas expanded by 12%, leading to a substantial loss of green cover.This urban growth reduced the city's carbon absorption ability and weakened its flood mitigation potential by 13%.The study highlighted a reduction in water runoff retention potential within built-up areas, where human infrastructure expansion contributed to a notable decrease in the land's capacity to manage runoff. However, the capacity of the hills to manage runoff remained unaltered and at full capacity."The decline is largely attributed to the disruption of natural drainage systems and unregulated construction along riversides and floodplains. This, combined with continued landscape alterations, is likely to increase the city's vulnerability to floods, a growing concern given Pune's increasingly erratic monsoon patterns," said Koparde."Our results underline the irreplaceable role of native geological and ecological features such as urban hills and wetlands in maintaining urban environmental health. As tropical cities like Pune expand, sustainable development can only be achieved by leveraging these native assets rather than undermining them," he said.The study focussed on decadal changes in the ecosystem, such as carbon sequestration, flood mitigation, heat mitigation, and vegetation in Pune city from 2013 to 2022.The city lost around 34% of its carbon storage capacity within a decade, and it was pronounced in the hilly regions, especially at Taljai hill. "A decline in carbon storage potential could impact the city's ability to mitigate climate change effects and maintain a healthy urban ecosystem," revealed the study.Researchers provided suggestions, including afforestation, sustainable land management, enhanced vegetation around water bodies, and urban forest initiatives to increase the same.The city also saw an increase in built-up area from 30% in 2013 to 43% in 2022 — underscoring rapid urbanisation and loss of barren land.This barren land, due to its location at the junction of the Western Ghats biodiversity hotspot and Deccan Plateau, was a scrub-savanna vegetated space."Tagging scrub-savanna or grassland systems as barren lands and converting them into other land-use categories is exerting severe pressure on the unique biodiversity of the region and decreasing productivity. In the case of Pune city, the hills are at the stake of conservation, as they are in the midst of the city," stated the study.Heat mitigation was also observed mainly at the hills and less so at the built-up areas, indicating limited or no capacity to mitigate heat. "This observation underscores the integral role of natural green spaces, such as the hills, in ameliorating urban heat island effects while accentuating the challenges posed by urbanisation and human development in impeding effective heat mitigation strategies," the study showed.The research also highlighted that to enhance resilience to floods, it is crucial to preserve the existing riparian vegetation around the Mula-Mutha rivers. "This vegetation acts as a natural buffer, helping to stabilise riverbanks, reduce runoff, and improve water absorption," the researchers stated in the study.Koparde added, "We strongly advocate for urgent policy interventions including the protection and restoration of urban hills, wetlands, and riverside green buffers. Tools like ecosystem service valuation models and integrated urban planning frameworks must be adopted to ensure that future growth is ecologically balanced and informed by data."