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Bio-diversity is an important natural resource
and needs to be preserved and conserved to
maintain the ecological balance of the whole
region. Bio-diversity is the general term used
to reflect diversify and abundance in nature and
includes all living things.
In Ha Long Bay it can be divided into 2
categories:
-
The
tropical forest ecosystem
-
The sea
-shore ecosystem
1. The tropical forest ecosystem:
The total number of plant species living on the
rugged islands in Ha Long Bay is still not
known, as many islands remain unexplored. There
are probably over a thousand species of plants,
the distribution of which is not uniform.
Instead, several different communities (species
of plants that always grow together) are found,
such as: mangrove, seashore plants, those of the
slopes or sheer cliffs, the summit plants and
those that grow around the mouth of caves and in
gullies. These plant species have adapted to
live on the limestone islands in Ha Long Bay.
Researchers of IUCN in Ha Noi surveyed the area
and found seven rare and unique species of flora
in Ha Long. These species have adapted to live
on the limestone islands in Ha Long Bay and are
not found anywhere else in the world. They are
Ha Long cycad, violet chirita, Ha Long fan palm,
woolly chirita, Ha Long balsam, schefflera and
yellow slipper orchid. According to the
statistics of the Institute of Ecology and
Biological Resources, the tropical forest
ecosystem in Ha Long and Bai Tu Long has 477
magnoliophyta species, 12 polypodiophyta species
and 20 mangrove flora species. It also listed a
total of 4 amphibious species, 8 reptile
species, 40 species of bird and 14 species of
animal.
2. The sea -shore ecosystem:
including wetland areas and sea ecosystem.
The wetland ecosystem in Ha Long Bay and
surrounding area includes 6 sub- ecosystems:
-
Tidal and mangrove ecosystem:
It is estimated that Ha Long Bay and its
environs contain 20 species of mangrove
plant. These mangrove forests of Ha Long
Bay play an important role as habitats
to many creatures and have a high
biological capacity. They provide a home
to 169 species of Polycheata, 91 species
of cyanophyta, 400 species of fish, 200
species of bird, 10 species of reptile
and 6 other species.
-
Hard bottom ecosystem - coral
reefs:
Coral reef ecosystem is one of the
specific characteristics of Ha Long Bay,
having a high biological capacity and a
water cleansing ability. They are
concentrated in the areas of Trai Cave,
Cong Do Island and Van Gio Island and
other places. Coral reefs here mostly
feature fringe lagoons, reef flats -
both inside and outside, crest, slope
and platform reefs.
At present in Ha Long Bay, it is
estimated that there are 232 listed
coral species. These belong to the
Coelenterate and include Anthozoa (coral
class) and Hydrozoa. The coral reefs in
Ha Long Bay are the home of 81 species
of Gastropada, 130 species of Bivalvia,
55 species of Polycheata and 57 species
of Brachyura.
-
Cave and “ Tung”, “Ang” (Lagoon)
ecosystem:
This is a special ecosystem. "Ang"
refers to the reservoirs, lying among
islands; “Tung” is the closed lakes and
their smooth waters. These favorable
conditions create this special
ecosystem, which is such a beautiful
feature of the Bay. For example: Tung
Ngon is home to 65 species of coral, 18
species of sea- weed, 40 species of
benthos and 4 rare species listed in the
“Red Book of Viet Nam”. Numerous caves
and grottoes have been restored for the
purpose of conservation and tourism
development on Ha Long Bay, though some
still keep their primitive beauty.
-
Soft bottom ecosystem:
This is a sea-grass ecosystem. It is
comprised of only 5 species of
sea-grass, however it is the habitat for
many other species. It also has the
advantages of preventing the creation of
waves and cleaning the water environment
by absorbing organic waste. It is
estimated that, at present, the number
of species living in sea grass ecosystem
includes 141 species of sea-weeds, 3
species of Polycheata (sand worms), 29
species of mollusc and 9 species of
Grustacea.
-
Tidal flats without mangrove
forest:
are found in the low tidal areas.
Molluscs (Shells) and sandworms
(Bivalve) are typical species living off
the tidal flats and have a very high
nutritional value, examples: sea
cucumber, Arca granosa and Meretrix.
Almost all creature resources of the
tidal flats are being over exploited.
* Aquatic ecosystem:
This marine ecosystem includes
phytoplankton, zooplankton, zoo-benthos and
nekton.
-
Phytoplankton:
These are the small animals drifting
about in the water, they can autotrophy
through the process of photosynthesis.
They contribute to the dissolution of
organic matter and thus help against
water pollution. According to the
results of site surveys, there are 185
Phytoplankton species in Ha Long Bay.
Zooplankton:
These too are small animals drifting
about in the water, they are the second
link in the nutrient chain (next to the
phytoplankton). The distribution of
Zooplankton is dependent on the water
layers and time. It is estimated that
there are 140 Zooplankton species in the
Ha Long - Cat Ba area.
Zoo-benthos:
These creatures live on the bottom of
the sea and have very high nutritional
value. Surveys showed that there are 500
zoo-benthos species in Ha Long area, of
which 300 are mollusc species, 200
Polycheata species (sand worms) and 13
Echinodermata species.
-
Nekton:
These animals can swim in the water by
themselves and migrate to look for food.
They breed or shelter in winter. It is
estimated that there are 326 nekton
species in the Bay.
Species multiply: In
2002 a survey on assessing and auditing Ha Long
Bay’s bio-diversity was conducted by management
authorities and researchers. They surveyed 9
areas in Zone 1 of the World Heritage: Dau Be
Island, Hang Trai Island, Bu Xam Islet, May Den
Islet, Coc (Toad) Islet, Veu - Dau Go Islet, Ki
Da Islet, Soi Van - Van Gio Island and Cong Do
Island. First observations revealed that Ha Long
Bay had maintained its bio-diversity and
species diversity, and more new species were
discovered.
Current figures indicate there are a total of
1,847 species and 30 cave-grotto species groups
in Ha Long Bay. Almost all the typical
ecosystems found in a tropical sea area converge
in Ha Long Bay, for example: coral reefs,
sea-grass, mangrove forests, and "Tung" and "Ang".
Ha Long Bay is home to 189 species of fish, 500
species of benthos, 355 species of plankton, 140
species of seaweed, 7 species of sea-grass and
34 species of mangrove (according to data
provided by the ‘National Conference on Ha Long
Bay Bio-diversity’. [December, 2003, Ha Long
City]
3. Diversity of Gene:
In April 2003, a survey of three areas of Ha
Long Bay, [Dau Be, Hang Trai and Cong Do]
conducted by Viet Nam and Italy, in cooperation,
showed that the Bay is the habitat of some rare
species such as: Trochus Niloticus, Techtus
Pyramis, Epitonium Scalarare, Atrina Vexillum,
Lutraria Rhynchaena, Photololigo Chinensis and
Sepia Pharaonis. Particularly, around 19
species of sponge have been identified for the
first time. These species not only have a high
bio-diversity value but also provide an
important marine medicinal resource. Its
favorable natural conditions give Ha Long Bay
its high bio-diversity value, displayed by the
diversity of species composition and gene.
Documents relating to Ha Long Bay's
bio-diversity:
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Ha Long Bay - A World Natural
Heritage, published by the
Ha Long Bay Management Department, 2002.
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Eco-tourism Development in
Combination with Conservation of Ha Long
Bay Heritage Area, written
by Prof. Dr. Pham Trung Luong, Deputy
Director of Research Institute of
Tourism Development.
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Wild Plants of Ha Long Bay,
written by Dr. Nguyen Tien Hiep,
published by the Ha Long Bay Management
Department, 2000.
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Reports issued to the National
Conference on Bio-diversity of Ha Long
Bay World Heritage Site,
December 2003.
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Quang Ninh Profile,
Set 3 and other relevant important
documents.
Source: Halong bay
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