Invasive Alien Plants Rapidly Transforming India’s Ecosystems: New Study Warns

A new study published in Nature Sustainability warns that invasive alien plants are spreading at an unprecedented pace in India, particularly in ecologically fragile regions such as the Western Ghats, the Himalayas and the north-east. Researchers report that their range has nearly doubled in these zones over the past two decades.

• Climate & Land-Use Change Accelerating Spread: The study highlights that climate change, land-use alterations and biodiversity disruptions are jointly driving the rapid expansion of invasive species. These pressures are creating severe socio-ecological risks and threatening millions who depend directly on natural ecosystems.

• Massive Exposure of People, Livestock & Farmland: By 2022, an estimated:
  • 144 million people,
  • 2.79 million livestock, and
  • 200,000 sq km of smallholder agricultural land were exposed to at least one new plant invasion.
  • Each year, around 15,500 sq km of natural areas are invaded, exposing 11,200 sq km of herbivore habitats to forage loss. Nearly 7 million people are affected annually by new invasions.

• Dominant Invaders Across Ecosystems: Almost two-thirds of India’s natural ecosystems now host at least 11 major invasive plant species, including Lantana camara, Chromolaena odorata, and Prosopis juliflora.
  • Chromolaena odorata is expanding fastest at 1,988 sq km per year, doubling its range in the Western Ghats and north-east within 20 years.
  • Prosopis juliflora, introduced to combat desertification, has spread widely in dry regions, displacing native grasses vital for wildlife and pastoral communities.

• Biome-Specific Drivers of Invasion: Wet-biome invaders (e.g., Ageratina adenophora, Chromolaena odorata, Mikania micrantha) expand with higher fire frequency, declining soil moisture and rising temperatures.
  • Dry-biome invaders (e.g., Prosopis juliflora, Xanthium strumarium) expand with lower fire frequency, higher soil moisture, increased grazing and greater rainfall.

• Threat to Livelihoods & Rural Stability: The study warns that invasions are heavily impacting agro-pastoral systems, reducing access to pasture, firewood and water. In some regions, communities are being forced to migrate. Species like Prosopis juliflora severely restrict access to essential daily resources, especially for marginalised households.

• Huge Economic Losses Over Six Decades: India’s economic losses due to invasive species between 1960–2020 are estimated at $127.3 billion (₹8.3 lakh crore), reflecting damage to agriculture, forestry and rural livelihoods.

• Call for a National Invasive Species Mission: Despite being among the world’s top invasion hotspots, India lacks a dedicated institutional framework or a national repository of effective management practices. The study’s authors urge the government to establish a National Invasive Species Mission focused on:
  • systematic scientific monitoring,
  • evidence-based management,
  • stronger quarantine systems,
  • inter-sectoral coordination, and
  • strategic long-term financing.

Source: DTE