472 BIODIVERSITY OF MANGROVES IN ESTUARINE ECOSYSTEMS OF RATNAGIRI DISTRICT Pratap V. Naikwade 1 , Ranjit B. Bansode 2 , Sagar T. Sankpal 3 and Bharati B. Jadhav 4 1 Pitre College, Devrukh-415804, Maharashtra, India. Mob. 09595821891, Fax: (02354) 241058, 2 Department of Botany, Aathalye Sapre Pitre College, Devrukh-415804, Maharashtra, India. 3 Department of Chemistry, Aathalye Sapre Pitre College, Devrukh-415804, Maharashtra, India. 4 Department of Botany, Dr. B.A. Marathwada University, Aurangabad-431001, Maharashtra, India. Received on: 10 October 2013, accepted on: 12 December 2013 Abstract:Biodiversity is prevalent in the tropical estuarine system, particularly in the inter tidal forested vegeta- tion known as Mangrove. Mangroves are salt tolerant forest ecosystem of tropical and subtropical intertidal regions near river mouths with high productivity. They are open systems with respect to both energy and matter and thus couple upland terrestrial and coastal estuarine ecosystems. Mangrove vegetation contributes to the primary production in the aquatic environment in the form of leaf and litter fall.Ratnagiri is a coastal district of Maharashtra state, situated in the western ghat area of Sahyadri, Western coast of India. It has 167 km long sea coast of Arabian Sea which contains ecologically important area full of biodiversity. During the last 25 years, about 40% reduction in the mangrove cover of Maharashtra has been due to human interference and State Kharland Development Board. Some of the major problems faced by the littoral zone and the shore front areas of Maharashtra coast are related to coastal erosion, siltation, pollution, destruction of mangrove swamps, salt marshes, sea level rise, landslides and slope failure, pressure of population, industrialization, road transport etc. The national committee on mangroves, formulated by Ministry of environment and forests has identif ied man- groves of Ratnagiri as one of the 15 selected areas under threat. The earlier studies do not give the estimate about the number of species, area covered significantly varies and clear-cut information is lacking. So objective of present paper is to study biodiversity of mangroves along coast of Ratnagiri district for conservation of estuarine ecosystem and mangroves for sustainable development. Different estuaries of Ratnagiri districts were visited frequently for study. Plants were identif ied with the help of standard literature and floras. The studies revealed that Ratnagiri district shows biodiversity of mangroves with 20 species with 15 genera. Sonneratia, Avicennia were the more common genus with three species each. The present floristic diversity of Ratnagiri shows that species like Bruguiera parviflora recorded by the earlier workers have become locally extinct. Importantly, a rare mangrove species Xylocarpus granatum has been recorded from a few localities close to mangrove patch of Jaigad. Though this species has been categorized as Least Concern in the IUCN red list, the conservation notes on it emphasize on its declining populations all over the country due to severe habitat loss. Immediate efforts should be made by Government, concerned authorities, policy makers to conserve estuarine ecosystem and biodiversity of mangroves by different methods such as education and awareness programmes to local people about ecologi- cal values of mangroves for sustainable development. Key words: Anthropogenic, Coastal, Conservation, Endangered, Sustainable development INTRODUCTION Mangroves are salt tolerant forest ecosystem of tropical and subtropical intertidal regions near river mouths. It includes a variety of trees that grow in saline coastal sediment habitats in the tropics and subtropics. The term ‘mangrove’ describes both the ecosystem and the plant families that have developed specialized adaptations to live in this tidal environment (Alka Shiva, 2006; Tomlinson, 1986). Mangroves dominate three-quarters of tropical coastlines (Hogarth, 1999). Mangroves support the conservation of biological diversity by providing habitats, spawning grounds, nurseries and nutrients for a number of animals (Takle, 2007). These include several endangered species and range from reptiles and amphibians to mammals. The role of mangroves in the marine food chain is crucial (Kapetsky, 1985). Climate of any *Email: naikwade.pratap@gmail.com Journal of Aquatic Biology and Fisheries Vol. 2/2014/ pp. 472 to 475