BANGALORE: A recent study has mapped the distribution and diversity of mangrove forests along the West Coast using high resolution satellite data and ground surveys.
The study has brought to light the success of afforestation programmes by the State Forest Department.Mangrove forests are trees and shrubs that grow in saline coastal environments in tropical areas around the world. They keep the coastline safe.
Researchers from the Centre for Ecological Sciences (CES) at the Indian Institute of Science (IISc), Bangalore, studied four estuaries along the Western Coast of Karnataka -- the Honnavar division of Uttara Kannada district - and showed that the area has about 3 sqkm of mangrove forests.
A common trend was an increase in area under vegetation in the last decade or so. This is contrary to the Forest Survey of India (Government of India), which indicates that the area has almost no mangroves.
This increase of natural vegetation was accompanied by a decrease in the area seen as open fields, providing strong evidence that that these open fields were converted to mangroves, by a combination of natural regeneration and forest department-sponsored afforestation programmes, a press release from IISc said.
All this information was obtained by simply analysing photographs from space obtained by the technique of remote sensing to take high-resolution ‘photographs’ of the globe. “The study period was about 12 months, done at the invitation of the Karnataka Forest Department, Honnavar Division,” said Dr T V Ramachandra, a co-author of this study who leads the Energy and Wetlands Research Group at CES, IISc, Bangalore. “(Considering how Land sat data is available for free), postgraduate students can implement similar work in other parts of (the) Indian coast.”
They have tried to find out the identity of tree species in a particular area from satellite images. The distribution of about five different species was found in the area.Ramachandra added, “It helps in decision making,” he added.
“The Forest Survey of India report indicated that there is little or no spatial coverage of mangroves in Karnataka. Hence, Karnataka has been deprived of Central funds for management and afforestation,” he observed.
Mangroves respond quickly to afforestation efforts. They are the filters the seas; they provide a breeding ground for fish and shrimp, stabilise the coastline and mitigate the impact of cyclones and tsunamis.
The paper appeared in the Journal of Geophysics and Remote Sensing on October 30.