The Fishbone model of irrigation has helped restore the mangrove cover in the Krishna Wildlife Sanctuary (KWS) in nearly 6,000 hectares since 2006. In this model, the water from a creek is diverted to the targeted site through feeder and field channels, converting the barren land with high saline content into fertile land that supports the survival of mangrove plant species.
The shape of the fishbone allows the water to reach every nook and corner of the field channels. “The feeder channel is indirectly connected to the irrigation canal of the Krishna. The river water mixed with the sea water in the backwater channels will help reduce the salinity in the soil on which the channels are dug up for raising the mangrove plants,” said Allaparthi Appa Rao, mangrove expert associated with the model since 2006 in the 192 sq. km-KWL. Mr. Rao leads the restoration initiative of the AP Forest department. The seeds of the mangrove plant species are sown on the banks of all the channels once the salinity is reduced to the required level for the survival of the plants.
“Restoring the cover through the model demands a mix of expertise in understanding tides, sea water parameters, irrigation and botany. On record, the mangrove cover in nearly 6,000 hectares has been raised since 2006-07 by adopting the model,” Mr. Appa Rao told The Hindu . The 6,000 hectares were previously used for aquaculture.
M.S. Swaminathan Research Foundation (MSSRF) Executive Director Dr. Selvam has been credited in popularising the model.
“Dr. Selvam [then Sr. Scientist, MSSRF] tested the model on a 10-hectare site in the Pichavaram mangrove forest in Tamil Nadu which paved the way for conservation and restoration of the mangrove in the KWL,” Masula-based MSSRF Senior Scientist Rama Subramanyam said.
