VIET NAM ACADEMY OF SCIENCE AND TECHNOLOGY
GRADUATE UNIVERSITY OF SCIENCE AND TECHNOLOGY
……..….***…………
NGUYEN THI TUONG VI
FISH RESOURCES IN ECOSYSTEMS IN COASTAL AREAS OF
QUANG NAM – DA NANG PROVINCES
Major: Hydrobiology
Code: 62 42 01 08
SUMMARY OF THESIS ON
DOCTOR OF PHILOSOPHY IN BIOLOGY
NHA TRANG – 2017
The dissertation was completed at:
- Institute of Oceanography – Viet Nam Academy of Science and Technology
- Department of Science and Marine Technology – Graduate University of
Science and Technology – Viet Nam Academy of Science and Technology
Scientific Supervisors: 1. Assoc. Prof. Dr. Vo Si Tuan
2. Dr. Nguyen Van Long
Institute of Oceanography – Viet Nam Academy of Science and Technology
1st Reviewer: Assoc. Prof.
2nd Reviewer: Assoc. Prof.
3rd Reviewer: Assoc. Prof.
The thesis had been defended at:
- Institute of Oceanography, No.01 Cau Da, Nha Trang City, Khanh Hoa Province
- At hour , Date 201
The thesis can be found at:
- General Sciences Library of Ho Chi Minh City
- Library of Graduate University of Science and Technology – Viet Nam
Academy of Science and Technology
- Library of Institute of Oceanography – Viet Nam Academy of Science
and Technology
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INTRODUCTION
1. Preface
Fisheries management policy is increasingly focused on protecting
ecosystems and individual fish resource groups. The first idea of
ecosystem-based fisheries management was mentioned in the
Stockholm Declaration in 1972, but until 2003 the FAO officially
published a publication dealing with the ecosystem approach in The
Ecosystem Approach to Fisheries (EAF) or the Ecosystem-Based
Fishery Management (EBFM). This is a new approach and effective way
of management. One of the concepts put into use is the ecological -
connectivity. Sheaves (2009) defines ecological - connectivity as the
movement of organisms from one habitat to another by the seasonal to
complete their life cycle. With an ecosystem-based fisheries
management approach, understanding the ecological - connectivity of
the important fish resource will enhance ecosystem management and,
at the same time, emphasize that in a marine protected area It is
necessarily includes many of the inhabitants.
Vietnam coastal has the distribution of tropical ecosystems such as
coral reefs, mangrove forests and seagrass beds. Like many other
countries in the world, the deterioration of ecosystems and the
deterioration of coastal resources have been occurring at fast pace in
many places over the last few decades. This is due to overexploitation
and lack of understanding of marine ecosystems as well as concern for
immediate benefits without paying attention to long-term ecological
consequences. There have been many studies of fisheries resources in
coastal ecosystems as a basis for proposing management solutions, but
studies often focus on the fishing industry structure, productivity,
groups of main species and the change of resources under human
impact. In recent years, there have been some marine areas that have
applied ecosystem-based fishery management approaches such as Phu
Quoc or some coastal habitats in the South China Sea, but this approach
is still unexplored. There is still a lack of scientific basis, especially the
data on ecological - connectivity . Therefore, many of the current
fisheries management documents is only focus on the size of the fish,
the size of the net or harvesting season. There are almost no clear,
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specific rules for the protection of spawning, nurseries areas or habitats
that play an important role in the life cycle of important species.
The coastal areas of Quang Nam-Da Nang have a diversified
distribution of typical marine ecosystems such as soft bottom, seagrass
beds, coral reefs, estuaries and mangrove forests. These ecosystems are
also under pressure from over-exploitation and exploitation by
destructive fishing gears. The protection and management of coastal
resources in the Quang Nam-Da Nang coastal zone has been difficult by
the delimitation of marine management boundaries based only on
geographic features, administrative, rather than ecological, biological
features. Therefore, the study on fish resource characteristics and
ecological-connectivity of important fishery resource in Quang Nam-
Danang coastal is a solid scientific basis for proposing ecosystem-
based management solutions. So we do the thesis: " Fish resources in
ecosystems in coastal areas of Quang Nam-Da Nang."
2. The objectives of the thesis
Provide data on fishery resource exploitation status and their
characteristics, and ecological – connectivity of important fishery resource,
this is the basis for proposing fishery management solutions in the coastal
of Quang Nam - Da Nang.
3. The contents of the thesis
1 - Basic characteristics of ecosystems and fish resources.
2 - Analyze and compare fish resources characteristics among ecosystems.
3 - Ecological – connectivity of the orange-spotted spinefoot (Siganus
guttatus) in coastal habitats.
4 - Analyze the impacts in fisheries management.
5 - Propose solutions for fishery management related to ecosystems.
4. The significance of the thesis
To provide data on fish resources, propose solutions to improve the
management effectition and utilization of fish resources in the coastal
ecosystems of Quang Nam-Da nang.
NEW FINDINGS OF THE THESIS
1. The thesis is considered to be the most comprehensive and complete
analysis of ecosystem characteristics, species diversity and status of fish
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resource exploitation related to ecosystems in coastal coastal Quang Nam-
Danang.
2. Specifically, this is the first study to discover and examine the
ecological connectivity of the orange-spotted spinefoot (Siganus guttatus) in
different ecosystems through outlining the life cycle of the fish from
juvenile to adult. Accordingly, the seed stock in the Thu Bon estuary and
the adult species in the coral reefs of Da Nang and Cu Lao Cham belong to
the same population.This is the scientific basis for proposing ecosystem-
based solutions for fisheries management.
3. It is the first study to propose ecosystem-based solutions for fisheries
management in the coastal areas of Quang Nam-Da Nang.
CHAPTER 1: OVERVIEW
1.1. Fisheries studies in the world
1.1.1. Exploitation status
Fisheries studies in the world mainly focus on the current status of
fishing, including the following main directions: (1) Quantification of fish
yield ( 2) Main resource species groups, (3) Fish biology (4) Fisheries
management.
In the above research directions, output statistics and stock estimation
are one of the main fisheries research directions, conducted to assess the
current status of marine fisheries exploitation in each area and from which
make comparisons or forecasts, warn the world fisheries trends to ensure
that resources are properly exploited. The methods commonly used in
stockpiling are hydrodynamic methods, mesh-traction methods, capture fish
yield conversion methods, or the method of establishing the relationship
between yield and biological productivity.
Beside the direction of research statistical yield, estimation of reserves
and fluctuations of fish resources, research direction the main source
species groups also receive the attention of many scientists. Studies on yield
statistics, fish stocks estimates and fluctuations, and major resource groups
are conducted to develop fisheries management policies so that appropriate
harvesting can be ensured sustainable development. At present,