Mangroves: Relics of the past?

Deccan Herald 19 Feb 08;

Mangroves have been protecting our shores from erosion and tidal waves. They enrich the marine life and recharge groundwater. But over-exploitation and neglect has seen their degradation. Unless we act now, it can be too late, finds out Jayalakshmi K.

The 2004 Tsunami had clearly shown the beneficial impact of mangroves. Six hamlets that had mangroves were left untouched largely!

Mangroves with their widespread mat of roots and rhizomes also trap sediments and help land building, preventing shifting of coastline sand. They dissipate winds, tidal and wave energy during storms. With their rich biodiversity of species they also aid fishermen.

Yet, the story all over India is dismal. In Kerala particularly, the mangrove area which was once 700 sq km is now a pathetic 17 sq km!

"Relics of the past" as aptly observed! It is all in the hands of private land holders, Revenue Department, and others. "The Forest Department does not own any of the mangrove land," said Sidappa, from the department.

"People see it as mosquito breeding centres and hindrances to their fishing boats and nets," he said. Coconut groves that almost start from the beach, stonewalling of beaches to prevent erosion, sand mining, etc. have meant there is no space for mangroves.

Call it development or degradation of natural resources, the last 50 years has seen the country lose 50 per cent of its mangrove area. Pollution and oil spills, impounding of river waters, cultivation, cattle grazing, over-harvesting of the mangroves, etc. are some of the main reasons for this.

Director of the Institute of Wood Science and Technology Suresh Gairola says, "India accounts for 5 per cent of the world's mangroves with Sunderbans in West Bengal accounting for 46 per cent of it," he said. While mangrove degradation has been ongoing, due to some conservation efforts, the area had slightly increased by 415 sq km between 1987 and 2003.

The Ministry of Environment and Forests has taken up mangrove conservation since 1987 with 100 per cent central assistance when it identified 35 main mangrove belts in the country. But it was evident at a workshop on mangroves that not many authorities at the state levels were even aware of such funds.

In Karnataka, mangroves occupy a minuscule 8.7 sq km spread across Honnavar, Karwar, Mangalore and Kundapur in the estuarine systems of Kali, Gangolli and Aganashini. "There are no big chunks like in Andhra here. They are more like natural barriers to individual farmlands, and in some places to sea erosion," says R K Srivastav, DCF, Kundapura, to this newspaper. "To have mangroves as part of reserve forests is not possible here. Mangroves and man exist alongside here! It is also not possible to conserve by planting."

Sand mining and diving for seashells has made it impossible for mangroves to take root. He however believes it can be taken up as a measure against erosion against the costlier option of stonewalling.

A study taken up on the Karnataka coast by IISc found poor quality of mangroves, in terms of reduced biomass and carbon stocks, thanks to human pressure. Mangroves are also excellent storage points for carbon.

In TN, invasion of other species as also cattle grazing and firewood removal has been the problem. Impounding of rivers has also led to fall in reception of freshwater in the estuaries, and this has caused degradation of mangroves, as proven by low density biomass.

With awareness and artificial regeneration taken up with fund assistance of the MoEF, it is hoped that things will improve. Ecotourism has helped in some places too. In Pichavaram, for instance, the local people have been paid to buy boats in which to take tourists on a cruise down the canals lined by mangroves. It is a source of income. In AP, walking routes have been made alongside the canals. In Karnataka too there is a proposal for a similar activity.

Creating artificial channels for inundations of the wetland has helped in TN where such intervention has resulted in a 90 per cent increase in mangrove area from 1989-2002. Since 2005, under the World Bank aided Emergency Tsunami Rehabilitation Project, the government has been able to increase the area further.

In AP, which has over 582 sq km of mangroves, some large chunks in the Krishna and Godavari estuaries, the fertiliser units that discharge nitrogen and ammonia effluents into the water was cited as a major threat to mangroves, as also aquaculture and spread of disease. The Forest Department has restored 20 sq km, says CCF Manoranjan Bhanja. Channel digging for artificial inundation has provided economic activity to the locals and has helped.

In Mumbai, the situation is bleak, as narrated by Shree Bhagwan, CCF, Thane. "Restoration of mangroves is the last priority where all land is reclaimed for land development by real estate sharks, to make Mumbai a Shanghai!" He believes that half of New Mumbai has been built on erstwhile mangrove land. Wetlands are being used to build slums, dump sewage and industrial waste and as garbage dumps!

However, with private participation like that of Godrej which has helped conserve 7 sq km of mangroves in Thane could be the solution. In Kerala, there is a plan to buy land from the private parties to conserve vanishing mangroves.

With the tools of satellite based remote sensing and imagery, it is now possible to monitor mangroves. Getting into the swamps can be a tough job and satellite pictures can be a big help. But it is unfortunate that while these tools are available, they are not being used to their full potential, according to space agencies.

More awareness among the public on the importance of mangroves, increased participation of all stake holders and an enlightened authority can reverse the fast-vanishing mangroves.