Jungle of the Roots: Mangrove restoration in Pulicat Lake

Mangrove samplings being prepared at CReNIEO in Pulicat

Pulicat: Destruction of natural mangroves in Pulicat Lake began with invading Dutch East India Company ships in the late 16th century. Ironically, the Tamil name for the lake, ‘Pazhaverkaadu’ translates to ‘jungle of the roots’. The Dutch axed away much of Pulicat’s rich Rhizophoraceae mangroves to construct the Fort Geldria in 1613, the erstwhile capital of the Dutch Coromandel in India.

Over the centuries, spreading urbanisation and industrial pollution have shrunk the mangrove vegetation to thin patches along the brackish coastline of Pulicat. The lake’s dwindling biodiversity has endangered around the 13,000 fisher-folk dependant on it. “The income of fishermen has fallen from Rs. 15,000–20,000 to Rs.1000–2000 a month. Women and youngsters have moved from fishery to wage-work at chocolate and paper industries,” said Mr. Meer Shah, Project Coordinator of Centre for Research on New International Economic Order (CReNIEO), an NGO dedicated to mangrove restoration along the Pulicat Lake since 2009.

The process of Mangrove restoration begins with a study of three land characteristics — Tidal Frequency, Soil Salinity, and Fresh Water Availability. Once a patch of land is identified as suitable, several Ecological Mangrove Restoration (EMR) canals are built through it to channel in fresh water.

A necessary count of 1000 to 2500 seedlings is required per hectare of land for proper restoration. These seedlings are either grown into saplings in a mangrove nursery or directly planted on the site. Wild seedlings that may not survive are transplanted into the nursery-grown saplings. Seeds are also scattered on the water surface to float around and find their own place to grow. The soil is loosely pressed after planting to avail sufficient oxygen for the plants. Compost or fertilizers are avoided, ensuring the magroves become dependant on natural nutrients.

CReNIEO has planted 50,000 saplings in the last eight years and provided community development services such as healthcare, livelihood and education to fishing communities in 25 villages surrounding the Pulicat Lake.

Mangroves are salt-resistant small shrubs and trees, well adapted to oxygen deprived, waterlogged mud. They act as a buffer zone and avert coastal erosion, blocking tsunamis and cyclones at the river estuary. They provide nursery and breeding shade to tiger prawns, mullets, shrimps, clams, oysters, green crabs and turtles. They encourage livelihood by fostering fishing and production of charcoal, firewood, timber, medicinal plants, shellfish and seaweeds. The Pulicat Lake Bird Sanctuary owes its diverse family of flamingos, sandpipers, herons, redshanks, gulls, spoonbills, parakeets, sunbirds and kingfishers to the mangroves vegetation.

Industrial pollution has massively affected the lagoon in the last 20 years. The Arani and Kalangi rivers carry in drainage replete with fertilizers, petrochemical waste and pesticides. Crab culture ponds and fish processing industries also discharge effluents into the lake. Toxic slurry of fly ash and hot water from the North Chennai Thermal Power Station (NCTPS) is another major source of pollution. In the last 10 years, two harbors have propped up along the coast — the Kamarajar Port and L&T’s Kattupalli Port. These shipyards have further thinned the mangroves.