By Umashankar Mishra
New Delhi: It is an invader nobody has seen on our borders but it can play havoc with the country’s biodiversity.
An alien weed, Ludwigia Peruviana, is posing a threat to biodiversity in parts of Assam, particularly the catchment area of river Dhansiri and eastern part of river Kopili, scientists have reported while expressing concern that it can spread to other areas in the northeast India.
The study, conducted by researchers at Assam Agricultural University and Tinsukia-based action group, Evergreen Earth, covered four distinct landscapes – marshlands, peat-lands, stream beds and bordering uplands spread over an area of 500 square kilometers. It was done in Karbi Anglong and Nagaon districts of Assam where the catchment area of Dhansiri and Kopili rivers is located. The weed is spreading rapidly in the region.
Popularly called primrose willow, Ludwigia Peruviana , is a native of Central and South America. Its flower is pale yellowish in colour and the plant grows to a height of about 12 feet. It is an aquatic plant, which is now challenging the existence of local vegetation in various swampy areas around the world.
The invader has already caused considerable damage to the plant community of marshlands, researchers have said in the study published in journal Current Science. The weed flourishes in sandy and mineral rich soil of wetlands.