Abstract:
The coastal areas of South Vietnam provide a good ecological condition for the
development of seagrasses. The species composition is rather diverse compared to other
ASEAN countries. We have recorded 15 species. Some of which are very interesting due to
their large distribution areas, high density and biomass, for example Enhalus acoroides,
Thalassia hemprichii and Halophila ovalis. They form thick meadows or patches in littoral
zones, bays, lagoons, estuaries, aquaculture ponds and mangroves. H. ovalis is widely
distributed in different ecological conditions. E. acoroides adapts to develop strongly in
lagoons and creeks, while T. hemprichii grows as large meadows in littoral zones.
Seagrasses can grow together in mixed vegetation. However, in some areas they form a
thick monospecific stand vegetation.
Studies on plant and animal communities associated with seagrasses in the coastal areas of
Khanhhoa province, where seagrasses are considered rather abundant, showed a high
diversity of flora and fauna. Benthic brown algae Sargassum spp. and Turbinaria spp.
occurring with seagrasses, form a diverse habitat. Red algae are dominant (34%) in species
composition of epiphytic algae. 62 species of macro zoobenthos and 87 fish species have
been found. A number species of algae, zoobenthos and fish with a high economic value,
have been reported. They are fished all the year round.