Diversity and distribution of true mangroves in Myeik coastal areas, Myanmar

Abstract

A total of 21 species of true mangroves, namely Rhizophora apiculata, R. mucronata, Bruguiera gymnorhiza, B. sexangula, B. cylindrica, B. parviflora, Ceriopstagal, C. decandra, Avicennia alba, A. officinalis, A. marina, Xylocarpus granatum Heritiera fomes, X. moluccensis, Sonneratia alba, S. graffithii, Heritiera forms, H. littoralis, Aegialitis rotundifolia, Aegiceras corniculatum, Excoecaria agallocha and Nypa fruticans were recorded from five study sites; Kapa, Masanpa, Panadoung, Kywekayan and Kyaukphyar in Myeik area from December 2017 to July 2018. Among these, 2 species were Near Threatened (NT), 1 species was Critically Endangered (CR) and 1 species was Endangered (EN) under the IUCN Red List. Rhizophora apiculata, R. mucronata,Avicennia officinalis, Sonneratia alba, Aegiceras corniculatum, and Nypa fruticans were distributed in all 5 study sites whereas Bruguiera gymnorrhiza and Heritiera littoralis are rarely found only in one study site. Kapa was designated as an area of the most abundant species composition representing 17 species, whereas Kyaukphyar representing 12 species as the least composition. The mangrove area in Kyaukphyar is the most degraded area among the study sites, due to urban development and industrialization. The environmental parameters such as salinity and temperature of seawater, and temperature and pH of soils of each study site were presented.