Invasive plant species are taking over Indian forests, rapidly proliferating and severely affecting native biodiversity. This is harming the ecosystem, human health and causing economic and environmental losses. These are alien species that have come into the country with human and avian migrations. A study published in the Journal of Applied Ecology estimated that two-thirds of the country’s forests are threatened by 11 invasive plant species—including Lantana camara, Prosopis juliflora and Chromolaena odorata. The nationwide survey conducted by researchers from institutions including the Wildlife Institute of India and Aarhus University of Denmark found that alien plant species had invaded 3,58,000 sq km of forest area.
This adds to the burden of deforestation. According to Global Forest Watch, an online platform providing real-time data on forest cover change, India has lost a whopping 2.33 million hectares of tree cover between 2000 and 2023, 95 percent of which occurred in natural forests between 2013 and 2023 due to anthropogenic factors. The study also showed that invasive plants pose a threat to the top predators in the wild whose survival depends on a healthy, abundant herbivore population. The latter’s survival and health in turn depends on grazing in invasive plants-free habitats. The rise in man-animal conflict is partly because the herbivore population is depleting due to lack of food.
Invasive species affect crucial functions like the timing of nitrogen cycles, water availability and carbon storage on which native plants depend. This forces an adverse cascading effect on others dependent on forest resources, jeopardising the ecosystem and affecting other species. The losses incurred as a result are estimated to run up to about $182.6 billion.
Some forest research institutes in the country like the Bengaluru-based Institute of Wood Science and Technology are trying ways to put invasive plants to good use, while eliminating them from forests. Unlike deforestation, invasive species threaten the ecosystem in a non-anthropogenic manner. Therefore, solutions do not lie in legislation. The urgent need is for out-of-the-box technological approaches. The problem of invasive species has largely remained away from the public gaze till now. But it’s a potent threat to India’s crucial wealth—its forests.