Aravallis losing 13.8% more soil annually despite rising forest cover: Study warns of erosion crisis

India’s oldest mountain range, the Aravalli Range, has witnessed a sharp rise in soil erosion despite an overall increase in forest cover, according to a new study.

Researchers from O.P. Jindal Global University and Indian Institute of Technology Kharagpur found that the expansion of built-up areas across the Aravallis has grown by nearly 53 per cent, contributing to a 13.8 per cent increase in average annual soil loss between 2017 and 2024.

The findings, published in the journal Geographies, suggest that large-scale land conversion is undermining conservation gains made through afforestation efforts.

The research analysed land use and land cover patterns between 2001 and 2021, combining long-term moderate-resolution satellite data from 2001–2020 with high-resolution observations from 2017 and 2024 to better assess soil erosion trends.

The study identified steep slopes, fragile soils and mining zones as key hotspots of erosion in the mountain system.

Although the researchers observed a noticeable increase in overall forest cover at a broad spatial scale, finer analysis revealed rapid expansion of built environments and the decline of rangelands and croplands, which has accelerated erosive processes.

Scientists noted that the Aravallis are ancient and geologically primitive mountains, where soils are deep and ecosystems remain delicate and intricately balanced.

The mountain range is also among India’s most mineral-rich systems, containing both metallic and non-metallic mineral deposits and forming a crucial part of the country’s mineral resource base.

According to the researchers, replacing semi-natural vegetation with impervious built surfaces weakens the land’s natural protective mechanisms and increases vulnerability to erosion.

They further warned that ecosystem degradation in the Aravallis can have downstream ecological consequences, as the breakdown of the stabilising land matrix affects connected landscapes.

The study also found that human-driven landscape changes combined with rising climatic erosivity between 2017 and 2024 have intensified soil loss.

Researchers said the pattern reflects a broader global trend in ancient mountain systems, where the interaction between human activity and climate change is accelerating the degradation of fragile ecosystems.