Sea erosion hits Indian Ocean island paradise
Lakshadweep's blue lagoons and coral reefs threatened by coastal erosion and human activity
Port development and tourism promotion on the fragile islands are partly responsible
Study suggests harnessing wave and other renewable energy to replace diesel power generators
Lakshadweep with its 36 islands forms the northern part of the Chagos – Maldives – Laccadive Ridge and lie 400 kilometres off the Indian coast. With a total area of 32 square kilometres, the centrally-administered territory supports a population of 70,000 people.
A comprehensive study of the Lakshadweep by the National Centre for Earth Sciences Study (NCESS), Thiruvananthapuram, reveals severe coastal erosion by natural factors such as high wave activity, strong winds and tidal currents, as well as human activity that threatens the stability of the popular tourist destination.
Published in Springer Briefs in Earth Sciences - 2015, the study uses numerical modelling to assess the extent of erosion and suggests remedial measures that include reduced dependence on diesel for power generation and protection of the beaches.
The announcements made by the Lakshadweep administration on reducing diesel consumption and carbon emission include generating up to five megawatts of electricity with subsidies provided by the central government with the support of the UNDP’s GEF Biomass Power Project.
T.N. Prakash, head of coastal processes research at NCESS and lead author of the Springer study, tells SciDev.Net that the cost of wave power generation is estimated to be comparable to the present cost of shipping diesel from the Indian mainland to the islands.
N. P. Kurian, scientist and member of the board of studies in physical oceanography at the Cochin University of Science and Technology, tells SciDev.Net that the study is important for the fact that it “looks into the prospects and advantages of renewable energy sources like biomass, solar, wind and wave for multi-source power generation systems on the islands.”
The administration plans to popularise energy saving devices and appliances such as LED lighting systems powered by solar energy on the streets and in homes. Battery operated vehicles now plying on the islands are also due to be recharged off a solar grid.
Despite risks to the fragile reefs, the administration plans to facilitate visits by cruise ships and yachts on a model similar to that on the Maldives — a small island state that faces permanent inundation from sea-level rise by the end of the century. Since March, a ‘Long-Term Coral Reef Monitoring Programme’ involving a team of scientists has been in place in the Lakshadweep.
Prakash says that the “rare aquatic biodiversity and vast blue lagoons of the islands”, which are the main tourist draw, are also at risk from cyclones and deep depressions. He believes that a balance has to be found between conservation and tourism, described officially as the engine for socio-economic development of the islands.
Sheela Nair, researcher for the study, says that while short-term shoreline changes are seasonal, long-term changes need to be countered using layers of tetrapods, hollow concrete blocks and coir bags filled with pebbles — though these may hamper the fishing and tourism industries.
Coral reefs, lagoons and mangroves have already suffered from dredging activities for port development. Fisheries, inadequate sewage and solid waste treatment and unscientific tourism promotion on the islands are also contributing to the degradation, she says.
“While considering the limitation of resources in Lakshadweep, a new management policy with indigenous initiatives, a good mix of administration and science and technology inputs can be of immense help to the islands,” says Prakash.
>Link to full article in Springer
This article has been produced by SciDev.Net's South Asia desk.