Biodiversity
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Landscapes and typical ecosystems
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Diversity in the Forest ecosystems
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Diversity
in freshwater ecosystems
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Diversity
in coastal and marine ecosystems
Vietnam is one of the centres of
high biodiversity in the world. Biodiversity is expressed through
diversity in species composition and diversity in landscapes, and
ecosystems as well.
Landscapes and
typical ecosystems
Terrestrial landscapes of
Vietnam can be distinguished into mountains, highland, delta flat and
coastal lower flat. The sea can be distinguished into coastal waters, off
-shore, islands, and coral reef,
etc.
Terrestrial landscapes have
typical ecosystems such as forest, grass, savanna, agriculture, urban etc.
Aquatic ecosystems include river, stream, lake, pond, swamp, and coastal
and marine ecosystems such as coral reef, sea grass, littoral, estuary,
mangrove, aquaculture pond, lagoon, and bay.
The continental area of
Vietnam has been ecologically divided into the following biogeographic
zones: North-east, North-west, Northern mountains, Northern delta flat,
Central North, Central coastal area, Central highland, South Eastern flat,
and Mekong river delta.
Coastal zone is divided into
natural areas as follow: Mong Cai - Do Son, Do Son - Lach Truong, Lach
Truong - Mui Ron, Mui Ron - Hai Van, Hai Van - Dai Lanh, Dai Lanh - Vung
Tau, Vung Tau - Ca Mau, Tay Nam Bo, and off-shore islands.
Results from a number of
studies show that there are 4 major biodiversity centres in Vietnam: Hoang
Lien Son, Northern Truong Son, Central highland, and South Eastern. In these areas, some new mammals, birds
and plants were discovered in the end of the last century.
Diversity in the Forest
ecosystems
Forests in Vietnam have a
diverse and abundant flora and fauna. Forest covers 28.8% of the total
land area of the country, as estimated at the beginning of
1999.
- Flora :
In his publications on the flora of Vietnam,
Nguyen Nghia Thin (1999) has reported 13,766 species of plants in Vietnam.
Of these, 2,393 are lower plant species and 11,373 vascular plant species.
Ten percent of the plant species are reported to be endemic. The total
number of vascular (flowering) plants in Vietnam are estimated to be
between 15,000 to 20,000 species.
- Fauna :
So far, 307 species of Nematode, 161 species of Helminthes, 200 soil worms (Ologochaeta), 145 species of Acartia, 144 species of Arthropods, 113 species of Collembola, 5,155 insect species,
258 species of Reptilia, 82
species of Amphibians, 828 bird
species, and 275 mammal species and subspecies have been recorded in
Vietnam.
In the system of nature reserves in Indochinese area of IUCN, species composition and endemism of Vietnam is considered higher as compared to others places in the sub-region. Of the 21 primate species occurring in the Indochinese sub-region, 15 species are recorded in Vietnam, of which 7 species and subspecies are endemic. According to statistics of Vo Quy & Nguyen Cu (1995), the number of endemic bird species in Vietnam is estimated at about 100 species.
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Box 3.2. Causes of biodiversity
degradation In
general, the following four categories of threats are responsible
for the loss and degradation of biodiversity in
Vietnam: -
Habitat
destruction and loss : habitat destruction and loss can be traced to
anthropogenic activities such as logging (including of mangrove),
human-induced fires, land conversion, destructive fishing methods,
and natural calamities like earthquakes, natural fires, typhoons and
diseases. -
Overexploitation:
Population pressure, poverty and paucity of livelihood opportunities
all contribute to the overexploitation and destruction of country's
biodiversity. -
Chemical
or environmental pollution: some ecosystems of wetland and swamps
are polluted by hazardous wastes from industrial plants, mine
tailings, agriculture fertilizers and pesticide run-off, and even
household wastes. Oil pollution due to shipping activities occurs in
the coastal estuarine waters. -
Biological
pollution: the introduction of exotic species can cause the
extinction of
indigenous species either directly through predation,
competition, and hybridization or indirectly through parasites and
habitat alteration. |
Diversity in freshwater
ecosystems
Inland freshwaters of Vietnam
are endowed with a rich diversity of flora and fauna including algae,
aquatic macrophytes, aquatic invertebrates, insects and fishes.
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1,402 species of algae have been identified in 259
genera belonging to 9
phyla.
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782 species of aquatic invertebrates have been
identified; of which crustacean has 48 species, and 4 genera, which are
described in Vietnam for the first time. Two groups of shrimps and crabs
have 52 species, of which 2 genera and 27 species ( 52% of total species)
are considered as endemic to
Vietnam or Indo-Chinese area (Dang Ngoc Thanh,
1999).
- 544 fish species belonging to 228 genera, 57 families, 18 orders are recognised in the country. Number of endemic fishes is estimated at approximately 35 species.
Diversity in coastal and
marine ecosystems
Results of inventories and
surveys so far conducted in Vietnam's coastal and marine ecosystems
indicate that 10,837 species of marine plants and animals exist, belonging
to various groups as follows:
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Flora: 537 species of algae, 662 species of macrophytes, 15 species of
seagrass. Mangrove flora has 94
species.
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Zooplankton: 468
species
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Benthic fauna: 6,337 species of benthos, 225 species of marine shrimps, 298
species of hard corals (Scleractinia)
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53 species of cephalopods have been
identified.
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2,038 fish species belonging to 717 genera, 178 families
have been recorded.
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Various animals: 50 species of marine
snakes, 4 species of tortoise, and 16 marine mammal species have been
identified.
Diversity in agriculture
(Agrodiversity)
Biodiversity of cultivated plants of Vietnam is
rather high. According to the statistics, 734 species of popular plants
belonging to 79 families are cultivated in
Vietnam.
Livestock: domestic animals in Vietnam are diverse in species composition such as cow, buffaloes, horses, pigs, and freshwater fish species. Indigenous fish species for aquaculture includes 21 species in 23 genera and 11 families. The production of cultured fish (sea and freshwater culture) accounts for a considerable percentage of the total fishery production in Vietnam.
Biotechnology developed in Vietnam since the beginning of 1980s. It has played an important role in conservation and development of biodiversity, particularly in culture technology (plant tissue-culture), artificial fertilization (domestic animals), hybridization, graftage and pure breeding of new domestic livestock, and development of technology to preserve genetic materials like in-vitro, cell frozen technology and embryo technology, etc.