Fishermen point scientists to ‘river in sea’

K. S. Jayaraman

Fishermen plying on the eastern coast of India have helped scientists discover a fresh water ‘river' that forms in the Bay of Bengal just after monsoon season1.

Arrows showing origin of the 'river in sea' n the Bay of Bengal all the way to the end. Locations from where fishermen colelcted water samples are named along the coast.
© Gopalakrishna, V. V. et al.
The ‘river in the sea’ forms in northern Bay of Bengal at the end of the monsoon and ‘vanishes’ gradually after a while. About 100 kilometres wide, it flows southward hugging the eastern coast of India and reaching the southern tip after two and a half months. The seasonal river in the sea was discovered by salinity measurements of sea water samples collected by fishermen along the coast.

The Bay of Bengal receives intense rainfall during the monsoon. This, and the run-offs from the rivers -- Ganges, Brahmaputra, Mahanadi, Godavari and Krishna -- bring around 1100 cubic kilometres of freshwater into the bay between July and September.

"This very intense freshwater flux into a relatively small and semi enclosed basin results in dilution of the salt in seawater," says one of the lead researchers V. V. Gopalakrishna, a scientist at the National Institute of Oceanography (NIO), Goa. The diluting effect gets concentrated in the upper 40 metres of the bay waters, resulting in a stark contrast between surface freshwater and saltier water below, he says.

The presence of low salinity water (called stratification in oceanography parlance) over the Bay of Bengal prevents vertical mixing of sea water. This results in the accumulation of more heat in the near-surface layers, Gopalakrishna says. The sea surface temperature remains above 28.5°C, a necessary condition to maintain deep atmospheric convection and rainfall. Similarly, strong salinity stratification close to the coast would mean more intense tropical cyclones, he says.

Rs. 95 crore for Raigad fishermen

In the highest compensation it has ever awarded, the National Green Tribunal has directed ONGC, the Jawaharlal Nehru Port Trust (JNPT) and the City & Industrial Development Corporation of Maharashtra (CIDCO) to pay Rs. 95.19 crore to the traditional fishermen families of Raigad district in Maharashtra.

V.R. Kingaonkar and Ajay Deshpande (Expert Member), sitting on the NGT (Western Zone) Bench in Pune, passed the order on February 27, on an application filed on behalf of the families who had alleged loss of livelihood by projects of these companies.

The sum will be distributed equally among 1,630 families.

To undo the damage done to the environment, the companies have also been directed to pay Rs. 50 lakh for planting mangroves and ensuring free passage of tidal currents in consultation with the Maharashtra Coastal Zone Management Authority.

The families which approached the NGT had claimed that project activities of these companies such as the reclamation of land, removal of Mangroves in the area that resulted in reducing breeding of fishes and narrowing the navigational route of the traditional boats had added to their misery by prohibiting them from their traditional right of fishing.

“The NGT held the companies responsible for causing degradation of environment due to destruction of Mangroves in the area, particularly, because of illegal reclamation, widening, deepening of channels and narrowing down width of Nhava- Sheva creek, which would disallow easy access to traditional route of the fishermen’s boats and destructing the aquatic life,” said Advocate Asim Sarode who represented the fishermen in the case.

Deltas Sinking and Shrinking as Dams Curb Steady Flow of Fresh Water to the Coast

CHENNAI: The deltas across the country are sinking and shrinking as dams and reservoirs has stopped the flow of fresh water to the sea besides the riuse in sea level, according to R Ramesh, director of National Centre for Sustainable Coastal Management.

Ramesh told Express on the sidelines of Multi Stakeholders Consultative Meeting on Coastal and Marine Zone Management at the M S Swaminathan Research Foundation that the dams and reservoirs have reduced the water flow to the coast and this is a global phenomenon.

He said that the major reason behind sinking and shrinking of deltas is sediment trapping by the dams built on the upstream rivers, which has resulted in oceans eroding and eating away deltas.

He said his Centre is also identifying the hotspots along the coastline that are vulnerable to pollution. He said National Centre for Sustainable Coastal Management has launched a study on the Indian coast and has completed nearly 50 per cent of it.

“We have completed the stretch between Kerala to Tamil Nadu and Kerala to Gujarat. Now we have to study the stretch between Goa to Gujarat and also between Tamil Nadu to West Bengal,” said Ramesh.

He said the study would identify eutrphication of estuaries as well as dangerous algae blooms besides various other factors. “We have hired the ship from National Institute of Ocean Technology and are conducting the study. The hotspots will be identified once the data will be collated,” he added.

He also said a national guideline for the development and implementation of Indian Coastal Zone Management plans in India has been developed. Currently, it is being implemented in Gujarat (Gulf of Kachchh), West Bengal (Digha to Sankarpur and Sagar Island) and Odisha (Gopalpur to Chilika and Paradeep to Dhamra). This will soon be implemented in other states also, he added. He said the ICZM guidelines would only be implemented in the vulnerable areas.

After Centre maps CRZ-1, TN Will Formulate Coastal Zone Management Plan

CHENNAI: Tamil Nadu will come out with its own Coastal Zone management plan once Ministry of Environment and Forest completes the mapping of Coastal Regulation Zone One as well as High Tide Line.

R Ramesh, director of Chennai-based National Center for Sustainable Coastal Management, an autonomous body of Ministry of Environment and Forest, told Express that the process to map CRZ-1 and High Tide Line is on the verge of completion and everything is likely to be in place in the next six months.

“Once CRZ-1 and High Tide Line is mapped then states will be coming up with a state costal zone management plan,” said Ramesh during the sidelines of Multi-Stakeholders Consultative Meeting on Coastal and Marine Zone Management organized by M S Swaminathan Research Foundation.

The CRZ-I consists of ecologically sensitive areas. These include mangroves, coral reefs, seagrass, salt marshes, protected areas or reserve forests besides horse shoe crab habitats, turtle nesting sites and bird nesting sites. It also includes geomorphologically important areas, which include sand dunes, sandy beaches, mudflats and inter-tidal areas besides heritage and archaeological sites.

He said that all these would be mapped in a digital format. He said the high tide line, the line on the land upto which the highest water line reaches during the spring tide, is also being mapped so that it could be used as a baseline for development as well as conservation activities along the coast.

“Both have been mapped aerially by the Survey of India,” he said. Ramesh also said the hazard line along Indian coast is being mapped by taking into account erosion and flooding of the coast.

It is being demarcated as the most landward boundary taking into account water level fluctuation, sea level rise and shoreline changes (erosion and accretion of the coast).

Govt moots ideas to sync green norms with growth

NEW DELHI: A number of steps have been taken in the past six months to speed up green clearances but the government is also examining 55 additional suggestions to achieve its twin goals of economic growth and environment protection.

Many of the suggestions, extended by a high-level panel of the environment ministry, will either be incorporated in the existing laws through suitable amendments or be made part of a new 'umbrella' law which may be introduced in Parliament during the Budget session.