India Lost More Forest Cover Than It Gained Between 2015 & 2019, Shows IIT Bombay Study

Last Updated:August 05, 2025, 14:53 IST

Using a different method to track forest cover, the study revealed that India lost nearly 18 sq kms of forest for every 1 sq km gained from 2015 to 2019.

Even where forest cover seems to be increasing on paper, the real ecological benefits and resilience of those forests may be limited. (Image: PTI)

India saw a net loss in forest cover from 2015 to 2019 – losing nearly 18 sq kms of forest for every 1 sq km gained – revealed a new study led by researchers from IIT Bombay and SASTRA Deemed University who tracked changes in the country’s forest landscape using a newly-developed framework.

The findings sharply contrast with the recent India State of the Forest Reports released by Forest Survey of India biennially, which have typically declared an increase in forest cover. An increase of nearly 3,976 sq km in forest cover shown from 2017-2019, 1540 sq km in 2019-2021 and 156.41 km2 in 2021-23 – bringing total forest cover currently to 7.15 lakh km2, almost 21.76 per cent of the total geographical area.

“Our results clearly show that most of the newly added forests during 2015–2019 were islets, highly-fragmented and ecologically vulnerable patches, which do not help much in connecting large forest areas," said co-author Prof Vasu Sathyakumar from IIT Bombay. “Our data source has a globally validated accuracy of over 85 per cent, making our connectivity results reliable. If FSI’s data were made available in GIS-compatible format, our methodology could be readily applied to it."

However, the researchers noted that the two reports are not directly comparable, as FSI does not assess forest connectivity, and uses a different criterion from the Copernicus Global Land Service (CGLS) to identify forests – defining forests as areas with at least 10 per cent tree cover, based on 23.5 meters resolution satellite imagery, without distinguishing between fragmented and continuous forests. On the other hand, IIT Bombay’s new framework used the CGLS dataset that applies a 15 per cent canopy threshold and a 100 m resolution.

Despite this, the study underscores the need to rethink how forest data is assessed and analyzed in the country, and underscores the need to move beyond the current quantity-based afforestation approach to explicitly incorporate structural connectivity into forest planning.

WHY IS THE STUDY SIGNIFICANT?

The study has important implications, as it highlights questions about the effectiveness of afforestation programs across India. Even where forest cover seems to be increasing on paper, the real ecological benefits and resilience of those forests may be limited. It shows that large, connected forest support biodiversity, resilience and regeneration, while fragmented forest hinder wildlife movement and survival – critical for species like tigers that need expansive habitats to thrive and avoid human conflict.

“So, afforestation activities that led to creation of ‘islets’ – small, isolated forest patches – which are most vulnerable- may not meaningfully contribute to forest health or connectivity. The afforestation programmes such as CAMPA or the National Mission for a Green India can benefit by focusing on strengthening existing ‘cores’ – large and intact forest habitats – which are most resilient to deforestation and could potentially yield better-connected, and ecologically-sustainable forests," said co-author Prof. RAAJ Ramsankaran from IIT Bombay.

According to the study, nearly half of the 56.3 sq. km. of gross forest gain occurred in Andhra Pradesh, Tamil Nadu, Karnataka, and Rajasthan, while Tamil Nadu and West Bengal together accounted for almost half of the 1,032.89 sq. km. of gross forest loss.

THE NEW METHOD TO TRACK INDIA’S FOREST COVER

The new framework recently published in peer-reviewed journal Environmental Monitoring and Assessment uses remote sensing data and open-source digital tools to map forest types and their connectivity at both the state and national levels. It relies on an image processing technique to detect and classify the structure of forest landscapes. The researchers applied the analysis to digital forest cover maps of India for the years 2015 to 2019, obtained from the Copernicus Global Land Service (CGLS) Land Cover Map.

Unlike most previous studies on forest cover, which report only net gains or losses, this study mapped forest loss and gain separately. “Our framework is fully extensible to finer scales, such as districts or protected areas, and can be used to analyse the impacts of linear infrastructure like roads and rail lines on forest connectivity in a more focused manner," added Prof Ramsankaran. “This makes it a valuable tool for long-term forest monitoring, planning and informed infrastructure development in and around forested areas."

Srishti Choudhary

Srishti Choudhary, Senior Assistant Editor at CNN-News18 specializes in science, environment, and climate change reporting. With over a decade of extensive field experience, she has brought incisive ground repo...Read More

Srishti Choudhary, Senior Assistant Editor at CNN-News18 specializes in science, environment, and climate change reporting. With over a decade of extensive field experience, she has brought incisive ground repo...

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August 05, 2025, 14:53 IST

News india India Lost More Forest Cover Than It Gained Between 2015 & 2019, Shows IIT Bombay Study

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