MINISTRY OF EDUCATION
AND TRAINING
VIETNAM ACADEMY
OF SCIENCE AND TECHNOLOGY
GRADUATE UNIVERSITY SCIENCE AND TECHNOLOGY
NGUYEN VAN GIANG
RESEARCH ON THE FISH FAUNA OF THE BANG GIANG – KY
CUNG RIVER BASIN IN VIETNAM
SUMMARY OF BIOLOGICAL DOCTRINE THESIS
HA NOI – 2018
The work was completed at: Graduate University Science and Technology -
Vietnam Academy of Science and Technology
Supervisors 1: Assoc.Prof. Dr. Nguyen Huu Duc
Supervisors 2: Dr. Nguyen Kim Son
Reviewer 1:
Reviewer 2:
Reviewer 3:
The thesis will be protected before the examination of PhD thesis at the
Academy, meeting at the Graduate University Science and Technology -
Vietnam Academy of Science and Technology at ... hour .... ', Date ... month
... 2018
The thesis can be found at:
- Library of the Graduate University Science and Technology
- National Library of Vietnam
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INTRODUCTION
1. The urgency of the thesis
Annually, the river basin of Ky Cung - Bang Giang provide important fisheries
to the people of Lang Son and Cao Bang, provides the main source of protein from
fish in the daily meals in each family. Though, So far no work has systematically
studied the fish fauna here. Besides that, the conservation of rare genetic resources
and biodiversity in the Bang Giang - Ky Cung River is a common concern of all
levels and sectors. However, in recent decades the Bang Giang - Ky Cung River has
been subjected to the strong influence of socio-economic activities: mineral
exploitation, domestic waste, industrial activities, increased use of chemical
fertilizers, pesticides polluting water resources, affecting the lives of fish and aquatic
species. Many species of economic value, rare species are rapidly reduced in the
number of strains, reducing biodiversity. Therefore, research into biodiversity
resources of fish species, assess the status of exploitation and adverse activities on
fish resources, contributing to the development of scientific basis for proposing
solutions to protect, use rational and sustainable development of fish resources of the
system. The Bang Giang - Ky Cung river system is urgent. On that basis, contributing
to the education and construction of animals in the country. Provide updated data, the
latest species composition, distribution characteristics, the status of resources, species
need conservation, so that local authorities refer to the development of biodiversity
protection plan. In general, fish in particular contribute to the overall development of
the locality.
Stemming from the above reasons, I chose the project “Research on the fish
fauna of the Bang Giang - Ky Cung river basin in Vietnam”
2. Objectives of the research
Identification of species composition, ichthyofaunistic diversity of Bang Giang
– Ky Cung river basin.
Cataloguing of fish species according to types of populated aquatic ecosystems
and habitats, distribution characteristics, determining the geographic distribution of
Bang Giang - Ky Cung fishery.
Investigation and assessment of the status of resources and fisheries in the
study area. Proposing some measures to protect and exploit rational fish resources in
the Bang Giang - Ky Cung river system, thus building the scientific basis for the
sustainable use and development of fish resources.
3. Main research contents of the thesis
Study on biodiversity composition of fish species in the Bang Giang - Ky Cung
river system.
Analysis of geographic distribution, distribution by aquatic ecology of fish
species in the study area.
Characteristics, properties zoogeography of the Cao Bang and Lang Son fish
fauna for the freshwater fish fauna of Vietnam.
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Assessment of the status of resources, demand for use, situation of exploitation
of people in the study area, serving for the management, protect fish resources,
measures for conservation of fish resources and development of fisheries resources in
the Bang Giang - Ky Cung river system.
CHAPTER 1. OVERVIEW
1.1. Freshwater fish study
1.1.1. History study of freshwater fish fauna of Vietnam
1.1.2. Brief history of the Bang Giang - Ky Cung river fish fauna
The first research in Cao Bang - Lang Son fishery was Vailant E., (1891,
1904), collected and classified 6 species and described 4 new species in Lai Chau,
recorded 5 fish species in Lang Son. Chevey P. (1930, 1932, 1936, 1937) studied the
composition of freshwater fish species in northern Vietnam including the fish fauna.
In 1978, in his book "The freshwater fishes of North Vietnam" Mai Dinh Yen
recorded fish fauna Cao Bang - Lang Son has 56 species belonging to 13 families 47
genara 5 orders.
Works "Freshwater fish of Vietnam" volume 1 of Nguyen Van Hao and Ngo Si
Van (2001) and "Freshwater fish of Vietnam", Volume 2, Volume 3 of Nguyen Van
Hao (2005), recorded 101 fish species belonging to 69 genera in Cao Bang - Lang
Son belong to 18 families and 5 orders.
In 2005, Nguyen Kiem Son conducted a survey on "fish fauna in Cao Bang
province. The result found 54 fish species belonging to 42 genera, 15 families and 5
orders.
In 2005, Ngo Sy Van, Pham Anh Tuan announced the fish fauna of two
provinces Cao Bang - Lang Son has quite diverse species composition of 107 species
of 74 varieties 22 families and 7 orders.
In China, there are studies on the composition of fish species: fish fauna of the
China Guangdong and Guangxi fish. The total number of species recorded in
Guangxi province is 290 species of fish, of which Tay Giang river borders Vietnam
receiving water from Bang Giang river - Ky Cung has recorded 125 species. In recent
years, the Guangxi fish fauna has recorded new species of fish: Acrossocheilus
malacopterus, Rectoris longibarbus and has recorded with distribution in Vietnam.
Thien Quang Huynh and I-Shiung Chen (2013), announced Opsariichthys
duchuunguyeni from the Bang Giang - Ky Cung River in Cao Bang - Lang Son
province, northeastern Vietnam.
Nguyen Van Hao, Vu Thi Hong Nguyen, Nguyen Thi Dieu Phuong (2015),
describe three new fish species belonging to Silurus Linnaeus, 1758, (Siluridae,
Siluriformes) found in northern provinces of Vietnam: Silurus caobangensis and
Silurus langsonensis.
As a result, there are 7 researches on the fish fauna of the Bang Giang - Ky
Cung river basin. The results show that there are 172 species belonging to 93 genera,
23 families and 7 orders.
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1.2. Overview of the natural and social characteristics of the study area
1.2.1. Natural features of the study area
1.2.1.1. Geographical location
The Bang Giang - Ky Cung river system is located northeast of Vietnam in Cao
Bang and Lang Son provinces. The area is 11,220 km2.
1.2.1.2. Morphological characteristics and topography
The Bang Giang - Ky Cung river system is located in the lower part of the
surrounding area, commonly known as the Cao - Lang low trough. Surrounding the
northwest, west and southwest are the highest mountain ranges in the Northeast, with
the highest peak being Pia Oac (1930 m). The Southeast is lowland with the highest
peak is Mau Son peaks 1541 m, Ba Xa 1166 m. In the North Pole, the highest peaks
are from 900 to over 1000 m.
In terms of river basin morphology, the Bang River has higher elevation and
basin slope than the Ky Cung River. The main river is also straight than the Ky Cung
River, the average width of the basin is smaller than the Ky Cung River. However,
the characteristics of the low trough is clearly shown
1.2.1.3. Climate characteristics
The location of the Bang Giang - Ky Cung river basin is relatively hidden for
the summer monsoon and directly welcomes the cold winter winds so it is dry and
less rain, and the rainfall increases gradually from the Southeast to the Northwest.
Also due to the location of hidden basins, deep in the continent that the rainfall
caused by the storm is low; Lang Son is 246mm / year and Cao Bang is 140mm /
year. Due to the strong influence of the winter wind and the obscurity of the sea, the
rainfall is reduced in the region, the shortest rainy season in the North.
1.2.1.4. Hydrological regime
Bang Giang river basin: The average density of rivers and streams in Cao
Bang province is 0.5 - 1.0 km / km2. Flood season from June to September every
year, peak flood in August, water volume in the flood season accounted for 70-80%.
In contrast, the dry season lasts eight months, the water in the season accounts for 20
- 30%.
Ky Cung river basin: The density of rivers and streams in Lang Son province
is relatively high, the average density of rivers and streams is between 0.6 - 1.2 km /
km2 compared to the average density of the whole country ( 0.6 km / km2). Divided
into two seasons: The flood season is concentrated in June to September each year,
the water volume this season accounts for 66 - 80% of the total water volume in the
year. Dry season lasts for eight months, but water volume accounts for 20 - 34% of
the annual flow.
1.2.2. Socio-economic characteristics
Cao Bang: Natural land area of 6,700,26km2. The population in Cao Bang is
522.4 thousand people, with a population density of 79.08 people / km2, Cao Bang's
economy is still underdeveloped. There are 28 ethnic groups in the province, 42.54%
of which are Tay majority; Nung ethnic group accounts for 32.86%; Dao ethnic