A newly conducted research has brought to the fore an alarming threat looming over the native vegetation and biodiversity in the Gulf of Mannar. The cause of concern is the impact of an alien invasive plant, Prosopis chilensis.
The invasion by this alien species is compounded by the destruction of the coral reef across numerous locations, even though its exploitation for industrial purposes is legally banned. Furthermore, some islands have been negatively affected by human settlements.
Understanding Invasive Species
An invasive species is a non-indigenous organism that triggers harm to the native species of a particular region. Such species can lead to the extinction of local plants and animals, lower biodiversity, compete with the native organisms for scarce resources and even modify habitats.
These species can be introduced into a new area through various means, such as ship ballast water, accidental releases, and more frequently, by humans.
A Closer Look at Prosopis Chilensis
The Chilean mesquite, scientifically known as Prosopis chilensis (Molina) Stuntz, is a small to medium-sized legume tree with a shallow and widespread root system. This common ruderal weed grows either singly or in groups and thrives in arid and semi-arid regions where groundwater levels range from 3 to 10 m below the surface. It is a drought-resistant plant and is indigenous to South American countries like Argentina, Bolivia, Chile, and Peru.
International Instruments on Invasive Species
Several international treaties and programs focus on the containment and eradication of invasive species.
The Convention on Biological Diversity (CBD), established during the Earth Summit in Rio de Janeiro in 1992, identifies biological invasion of non-native plant species as the second biggest threat to the environment, closely following habitat destruction.
The Convention on the Conservation of Migratory Species (CMS) or Bonn Convention aims to protect marine, terrestrial, and avian migratory species. Another objective is to control or eliminate invasive alien species that are already present.
The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) pursues the aim to ensure that international trade does not compromise the survival of wild plants and animals. It also acknowledges the problems posed by invasive species involved in trade which can threaten the existence of living organisms.
The Ramsar Convention is dedicated to the conservation and sustainable use of wetlands. It also focuses on the environmental, economic, and social impact of invasive species on wetlands and discusses methods of controlling them.
Gulf of Mannar: Bridging India and Sri-Lanka
The Gulf of Mannar is an inlet of the Indian Ocean, located between south-eastern India and western Sri Lanka. The gulf is bounded to the northeast by Rameswaram, Adam’s Bridge, and Mannar Island. Several rivers, such as the Tambraparni of India and the Aruvi of Sri Lanka, drain into it. It is most noted for its pearl banks and sacred chank.
The Gulf of Mannar Biosphere Reserve (GoMBR) features 21 islands that serve as habitats for coastal birds moving as far as the Arctic Circle. The GoMBR is India’s first marine biosphere reserve, with many islands having sand dunes along their coastlines, populated by salt-dominant plant species. Interesting ecosystems found on these islands include corals, seagrass, and mangroves.
