Species composition and the fluctuation of mangroves in Ha Tinh province

Abstract

Mangrove ecosystems in Ha Tinh concentrate largely in estuaries such as Hoi inlet, Sot inlet, Nhuong inlet, Khau inlet. The results have identified 22 species mangrove flora of 22 genera, 18 familia, 2 phylums included Polypodiophyta and Magnoliophyta in the study area. Magnoliophyta dominate with 94.4% of total familia and 95.5% of total species. Among 22 species in Ha Tinh mangrove flora, there are 9 true mangrove species (MS) and 13 mangrove associated species (MAS). Mangrove flora in Ha Tinh province has a lot of valuable uses, such as timber, medicinal, food, etc. In particular, there are 18 species of medicinal plants, 9 species of timber, 4
species of food, 4 species of fiber, 4 species for tannin, 2 species of bonsai and one for other utility. However, the mangrove ecosystems in Ha Tinh are influenced adversely by the impact of climate change and extreme weather.
Besides, the operation of socio- economic activities were caused the change of mangrove areas. These have posed many challenges for local authorities in planning, rational use of mangrove ecosystems to conservation and development as well as maximize the role of mangroves. Therefore, this paper has applied remote sensing and GIS technology to determine the variation of mangrove forest area in Ha Tinh province. The study results showed that there were 1392.79 ha of mangrove forest lost during the period from 2000 to 2012, average 116,1ha/year, the only remaining area of 775.83 ha of mangroves.