Spatio ecological characterization of structure function and change in the pichavaram mangrove forest Tamilnadu India

Abstract

Mangroves are shrubs and trees present in the intertidal areas of newlinetropical coasts. Worldwide, extensive pressure from anthropogenic and newlinenatural activities are causing degradation of mangrove forests and ultimately newlineleading to species extinction. Services provided by mangroves contribute to newlineecosystem balance and support livelihoods. This thesis aimed at studying the newlinestructure, functions and changes in the Pichavaram mangrove forest located in newlineCuddalore district of Tamil Nadu, and building a spectral library for newlinemangrove species found in this forest. The study of the mangrove forest newlinestructure explored species diversity, forest canopy and landscape composition. newlineNet photosynthetic rate, forest health, mangrove outwelling, socio-economic newlinedependency and response of mangroves to the 2004 tsunami were part of the newlinestudies of mangrove functions. The change in mangrove cover and shoreline newlinechange over a period of time formed part of the change studies. Spectral data newlinefor mangrove species were collected to classify and identify species based on newlinespectral reflectance. newlineMangrove structure: Phytosociological analysis was used to newlineunderstand species distribution. Importance value index calculated for species newlinepresent in the forest cover showed Avicennia marina dominating with 235, newlinefollowed by Rhizophora apiculata (14.61) and Excoecaria agallocha (10.54). newlineOther species scored less than 10. Simpson and Shannon diversity indices newlineindicated that the forest has low species diversity. Mangrove species such as newlineXylocarpus granatum, Kandelia candel, Bruguiera gymnorrhiza and newlineSonneratia apetala known to have been present according to historical newlinerecords for Pichavaram were not found/ very rarely spotted during the present newlinestudy. A study of the forest canopy density revealed that the centre of the newlinestudy area had high canopy density with mature Avicennia marina trees. newline