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Picture Courtesy:  The Hindu

Context:

A recent study indicates that 2,554 vascular plant species worldwide could potentially survive in a warming Arctic if introduced. Researchers have already identified non-native species in Svalbard, including meadow rue, signaling that ecological change is underway.

What are Invasive Alien Plant Species (IAPS)?

Invasive Alien Plant Species are plants introduced outside their natural geographical range that establish, spread rapidly, and displace native vegetation, leading to ecological imbalance and socio-economic losses. Their success is often due to fast growth, high seed production, and absence of natural predators in the new habitat.

The expansion of invasive plants is being intensified by climate warming, habitat fragmentation, land-use change, infrastructure development, altered hydrology, fire disturbances, and increasing human and livestock movement, all of which create disturbed environments favourable for colonisation.

Major invasive plants in India: Prominent invasive species include Lantana camara, Parthenium hysterophorus (Congress grass), Prosopis juliflora, Chromolaena odorata, and Eichhornia crassipes (water hyacinth), affecting forests, grasslands, wetlands, and agricultural landscapes.

Extent of invasion: Invasive plants are estimated to have spread across over 2.6 lakh sq km of India’s natural ecosystems, degrading habitats, reducing fodder availability, and lowering native biodiversity.

High-risk regions: Regions with extensive invasions include the Shivalik–Terai landscape, Northeast foothills and floodplains, Aravalli hills, central Indian forests (Dandakaranya), and the Western Ghats–Nilgiri complex, where disturbance and climatic suitability favour rapid spread.

Most vulnerable ecosystems: Open and disturbed ecosystems such as dry grasslands, savannas, scrublands, shola–grassland mosaics, riverine plains, wetlands, and the Ganga–Brahmaputra floodplains are particularly susceptible to aggressive plant invasions. 

Importance of Arctic warming for the threat of invasive plants:

• Climate suitability is expanding: Rising Arctic temperatures are lengthening the growing season and reducing extreme cold, allowing many non-native plants to survive. Studies suggest that over 2,500 global plant species could find suitable climatic conditions in a warming Arctic. 

• Loss of natural barriers: Earlier, permafrost, snow cover, and short summers prevented plant establishment. Warming is causing permafrost thaw, earlier snowmelt, and exposed soil, creating favourable conditions for germination and root growth. 

• Increased human access and activity: Melting ice is opening the region to shipping, tourism, research, and infrastructure development, increasing the likelihood of accidental seed introduction through cargo, equipment, clothing, and vehicles. 

• Ecosystem disturbance and colonisation: Construction, trampling, and soil disturbance create open and degraded patches, which invasive plants can colonise more easily than intact tundra vegetation. 

• Emerging high-risk pathways and regions: Introduction risks are rising through transport contaminants, stowaways, and escape from cultivation, particularly in vulnerable zones such as Alaska, Greenland, Iceland, Fennoscandia, and northern Russia.  

Challenges in managing invasive alien species:

• Expanding invasion footprint: Invasive plants have spread across over 2.6 lakh sq km of India’s natural ecosystems, with Lantana camara alone invading nearly 40% of India’s tiger habitats, severely degrading forest understories and reducing prey availability. 

• High economic and ecological costs: Globally, invasive species cause losses exceeding $423 billion annually (IPBES, 2019), while in India species such as water hyacinth (Eichhornia crassipes) clog irrigation channels, reduce fisheries, and increase water loss through evapotranspiration, as seen in Vembanad and Loktak lakes. 

• Rapid spread in disturbed landscapes: Infrastructure expansion, mining, overgrazing, and forest fires create disturbed habitats that facilitate invasion; for example, Prosopis juliflora has transformed large parts of Rajasthan and Gujarat, reducing native grasslands and affecting pastoral livelihoods. 

• Biological advantages and control difficulties: Many invasive plants produce thousands of long-viability seeds, regenerate after cutting, and release allelopathic chemicals; Parthenium hysterophorus, for instance, spreads rapidly along roadsides and fallow lands and causes dermatitis, respiratory allergies, and crop losses. 

• Weak early detection and monitoring systems: India lacks a real-time national surveillance network, and once species become established over large landscapes, eradication becomes nearly impossible, shifting efforts to costly long-term control. 

Initiatives for managing invasive alien species:

Global:

Convention on Biological Diversity (CBD) calls upon member countries, under Article 8(h), to prevent the introduction of invasive alien species and to control or eradicate those that threaten ecosystems, habitats, or native species. The Convention provides a coordinated global approach through guidelines, priority-setting, and capacity-building. 

Kunming - Montreal global biodiversity framework recognizes invasive species as a major driver of biodiversity loss and sets Target 6, which aims to reduce the impacts of invasive alien species on biodiversity and ecosystem services by at least 50% by 2030 through prevention, early detection, and effective management.

Scientific assessment and global databases: The IUCN Invasive Species Specialist Group (ISSG) plays a key role in scientific monitoring and knowledge sharing by maintaining the Global Invasive Species Database (GISD) and the Global Register of Introduced and Invasive Species.

Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), 1975, regulates cross-border trade in species to ensure that international commerce does not threaten biodiversity, thereby indirectly reducing the risk of invasive species movement through global trade networks. 

India specific initiatives

National biodiversity planning: India’s National Biodiversity Action Plan (NBAP) integrates invasive alien species management into national conservation strategies by focusing on prevention, risk assessment, habitat restoration, and long-term ecosystem monitoring.

Dedicated action plan for invasive species: The National Action Plan on Invasive Alien Species (NAPINVAS), launched by the Ministry of Environment, Forest and Climate Change (MoEFCC), provides a comprehensive framework emphasizing prevention, early detection, rapid response, control, and ecosystem restoration, along with institutional coordination and capacity building.

Information and awareness mechanisms: The National Invasive Species Information Center (NISIC) serves as a knowledge platform that disseminates scientific information, risk alerts, management techniques, and awareness material to support policymakers, researchers, and field agencies.

Biosecurity through import regulation: The Plant Quarantine (Regulation of Import into India) Order, 2003, administered by the Department of Agriculture, regulates the import of plants, seeds, and planting material through inspection, certification, and quarantine measures to prevent the accidental introduction of harmful invasive species. 

Conclusion:
Invasive alien species pose a growing threat to biodiversity, ecosystem services, and livelihoods due to their rapid spread, high ecological adaptability, and rising pressures from trade, land-use change, and climate warming; therefore, a strategy centered on strong biosecurity, early detection, coordinated management, and ecosystem restoration is essential to minimize long-term environmental and economic losses. 

Source: The Hindu