mumbai

Updated: Nov 04, 2017 14:56 IST

The health of mangroves in Maharashtra will now be monitored using real-time satellite images.

The state mangrove cell has approved a proposal from the Indian Institute of Space Science and Technology in Valiamala, Thiruvananthapuram, Kerala, and commissioned the research project to them on Thursday to track the health of mangrove forests using real-time satellite remote sensing data. Satellite images will be relayed to the forest department on a monthly basis in the form of reports to check area-wise increase, destruction cases and areas where restoration can be done.

Maps indicating the health of mangrove forests will be developed, which will include mangrove density, fragmentation, diversity, vegetation indices, erosion or accretion status, drainage density, sedimentation and blockages along river or estuary courses.

This is the first time any state in India has allocated its resources to survey mangrove cover along its coastline, said mangrove cell officials. “Many of the mangrove patches in the state, especially denser areas are inaccessible by foot or boats. We can see the edge of the creek but owing to degradation and siltation, it is difficult to enter these areas,” said N Vasudevan, additional principal chief conservator of forest, state mangrove cell. “We need an eye in the sky or more advanced technology to monitor the mangrove cover. This will help us to deploy manpower and resources from our space organisations and mangrove cell optimally.”

The proposal was received earlier this year and after several meetings to discuss the requirements from either side, it was cleared and the research project was awarded to the organisation, said Vasudevan. “We will now have more reliable data and periodic alerts available to us regarding vacant areas for plantation and problems with the health of the mangrove ecosystem,” he said.

According to a Forest Survey of India report, Maharashtra has 222 sq km mangrove cover, which is 4.7% of the country’s total mangrove cover (4,740 sq km). Of these, 143 sq km is open mangroves and 79 sq km dense mangroves. The report also said that in 2015, there was a 36 sq km increase in cover in Maharashtra, which was the highest recorded by any state in the country. Also, the cover has increased from 140 sq km in 1987 to 222 sq km in 2015.

HT had reported in January this year that the mangrove cell had tied up with the Indian Space Research Organisation (ISRO) to track real-time mangrove destruction in the state through an open source software — digital tracking through satellite maps – developed by Maharashtra Remote Sensing Application Centre (MRSAC). “This study is underway at ISRO and we are expected to receive the first set of results by this year end. Both research projects will help us understand the gap between destruction and restoration, and our where our focus should be,” said Vasudevan.

What will be tracked through satellite imagery?

The Indian Institute of Space Science and Technology will be developing a spatial database with baseline maps with mangroves within a buffer zone of 10km from the coast of five coastal districts of Maharashtra (Mumbai, Mumbai suburban, Raigad, Ratnagiri and Sindhudurg) with a scale of 1:6,000.

Additionally, canopy density, species distribution, hydrological network (surface water bodies such as estuaries, ponds, lakes, lagoons, rivers, streams etc.), and coastal geomorphology (tidal flats, mudflats, sand beaches, marsh land etc.), will all be identified through remote sensing data now.

(Source: The approved proposal by the Indian Institute of Space Science and Technology)

Mangrove cover that will be monitored

Location Moderately Dense Mangrove Cover (in sq km) Open Mangrove Cover (in sq km) Total (in sq km) Maharashtra 79 143 222 Mumbai City 0 2 2 Mumbai suburbs 24 24 48 Raigad 10 67 77 Ratnagiri 15 14 29 Sindhudurg 5 2 7 Thane 25 34 59

(Source: Forest Survey of India)