A note on the ancient mangroves of Goa, central west coast of India

Abstract

Organic peat deposits were observed 1.5 to 2.5 m below hinterland coastal plains, 20 km inland from the open sea coast. Red mud overlies peat. Sedimentological and mineralogical data revealed that peat was deposited in protected areas under calm marine conditions which were conducive for plant growth. The area appeared to have been colonized by mangrove populations as evidenced by wood fragments and a reddish brown tree stump encrusted with wood borers. Considering the utility of in situ mangrove peats as markers of past sea levels and paleoshorelines, the present study revealed that the hinterland of Goa was once occupied by lumuriant mangrove swamps under shallow water, low energy, sheltered environments during the recent geological past when the sea level was 1 to 3 m lower than at present.