ASSESSING THE CURRENT STATUS OF MARSH VEGETATION IN O LAU ESTUARY, THUA THIEN HUE PROVINCE USING GIS AND REMOTE SENSING TECHNIQUES

Abstract

Marsh vegetation (MV) are species living in marshland or coastal wetlands. The MV plays important roles as habitats, feeding and breeding grounds for species living in the wetland estuaries. The MV also contributes to reduce greenhouse gases, climate change resilience and creating livelihoods for local people. This study identified a number of species and distribution of marsh vegetation in O Lau estuary area. A number of environmental and biological characteristics were recorded based on field survey data and landsat 8 remote sensing image analysis. O Lau estuary wetland is recognized as high biodiversity area and has great potential for economic development. This study results showed that there are seven marsh species belonging to seven genera and six families with the averaged fresh biomass reached 2746.3 ± 607,9 g m^-2, the averaged canopy coverage reached 64,5 ± 14,2% and averaged shoot length acounted 1,38 ± 0,14 m for each sampling sites. Two marsh species Cyperus malaccenis and Phragmites australis gained the highest biomass value which Cyperus malaccenis had the greater value. Application of GIS and remote sensing with Landsat 8 image source, 30 m resolution, updated on April 25, 2019 have successfully estblished a map of the distribution status of MV and calculated the total area of ​​distribution in the region is 68,4 ha. The marsh vegetation are mainly distributed in Quang Thai, Quang Loi and Dien Loc communes and the largest area found in Quang Thai commune. This study findings would significantly contribute for assessing the status and build a database to serve the management stategies and conservation measures sustainable ultilization aquatic resources of the local cummunities around this wetland area.