Kochi: One of the biodiversity-rich uninhabited islands part of Lakshadweep has vanished due to coastal erosion and another four such territories in the sea are shrinking fast, claims a new study.

Parali I island, part of Bangaram atoll, which was 0.032 sq km in 1968 has been eroded to an extent of 100 percent, resulting in its inundation, says R.M. Hidayathulla in his research work.

Hidayathulla, who is from Androth in Lakshadweep, was awarded PhD in July by Calicut University for his work 'Studies on Coastal Erosion in Selected Uninhabited Islands of Lakshadweep Archipelago with Special Reference to Biodiversity Conservation.'

He conducted studies on the biodiversity of five uninhabited islands - Bangaram, Thinnakara, Parali I, II and III. Among these, Parali I - of Bangaram atoll in Lakshadweep, an archipelago of 36 islands in the Lakshadweep sea - has been inundated.

The study said the complete erosion and inundation of Parali I was pointing to the gravity of issues associated with the coastal erosion within the atoll.

It has been also noticed that all the five islets of Bangaram atoll had undergone coastal erosion.

"The results are indicative of the urgent measures to be implemented on each islet of the atoll to check further erosion," Hidayathulla told PTI.

His guide on the environmental studies, C.C. Harilal, said submergence of Parali I was noticed when he visited the Bangram atoll in 2011.

The data obtained were processed using Remote Sensing (RS) and Geographic Information System (GIS) softwares, Harilal said.

Only 35 islands?

"One island has submerged.. We can say Lakshadweep now is not an archipelago of 36 islands," he told PTI.

Hidayathulla said the assessment of the extent of geo-morphological changes associated with each island for a period of 35 years was carried out.

"As the absence of this island (Parli I) is noticed in both observations carried out in 2003 and 2007, it is assumed that the island has been subjected to complete erosion during the 1968-2003 period and an assessment of the exact year of its inundation requires data analysis for a span of 35 years extending from 1968," said the study.

Hidayathulla said a general trend in erosion has been noticed in almost all the islands he studied.

The magnitude of such events was higher in Parali group, evidenced by the complete erosion and inundation of the island Parali I, the study said.

Noted climate expert Chandra Bhushan hailed the work and said this was one of the very few studies done in India to establish the erosion and complete inundation of an island.

"It is now widely recognized that islands and coastal areas are going to get eroded and inundated due to rising sea levels because of increasing global temperature. India's coasts and islands, which are densely populated, are highly vulnerable," said Bhushan, who is also deputy director general of New Delhi-based advocacy group Centre for Science Environment (CSE).

"With the sea levels predicted to rise further, we should start preparing for building defenses to protect our coastlines and islands," he told PTI.

The magnitude of net erosion was higher in Parali I island (100 percent), which resulted in its inundation.

Apart from Parali I, net erosion was higher in Parali II (80 percent), followed by Thinnakara (14.38 percent), Parali III (11.42 percent) and Bangaram (9.968 percent), the study said.

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