Mangrove Conservation and Coastal Management in Southeast Asia: What Impact on Fishery Resources?

1. Welcome to My Presentation

2. Presented by
RASHIDUL ISLAM
REG: 05907
Level 3, Semester 2

3. A Presentation
On
Mangrove Conservation and Coastal
Management in Southeast Asia: What
Impact on Fishery Resources?

4. Outline
Abstract
Introduction
Objective
Study Area
Materials &Methods
Results & Discussion
Conclusion

5. Abstract
This paper focuses on relationships between mangroves and
coastal fish resources. A review of the literature highlights the
lack of quantified relationships. An estuarine fish community is
composed of three main assemblages, respectively from
continental, strictly estuarine or marine origin.

6. Introduction
One of the often stated reasons for rehabilitating mangrove
ecosystems is the importance of these systems to coastal fisheries.
This integrated approach has highlighted gaps in the information
available to managers, and allows us to suggest priority fields for
coastal management research, in biology as well as in economics.
Mangrove, Fishery, Estuary.

7. Objectives
 To reviews current knowledge about relationships between
mangrove extent and coastal harvests, focusing on Southeast Asia.
 To coastal environments and estuaries it appeared necessary to set
the problem at a larger scale
 To given practical guidelines in the field of coastal management

8. Study Area
Southeast Asia or Southeastern Asia is a subregion of Asia,
consisting of the countries that are geographically south of
Japan and China, east of India, west of Papua New Guinea
and north of Australia

9. Materials & Methods
In this field, four studies quantifying this relationship between
Mangroves and Coastal Resources have been published:
1. Turner (1977)
2. Martosubroto and Naamin (1977)
3. Paw and Chua (1989)
4. Robertson and Blaber (1992)

10. Contd.
Reference Formula X Y
Turner (1977) Y = 1.96 X — 4.39 Percentage of saline
vegetation in an hydro-
logical unit
Fish capture (tons)
Martosubroto and
Naamin (1977)
Y = 0.1128 X +
5.473
Hectares of vegetated
estuary
Annual shrimp yield
Shrimp production
(×1000 tons)
Paw and Chua (1989) Y = 0.8648 X +
0.0991
Logl0 of mangrove area Logl0 of penaeid shrimp
catch (tons)

11. Results & Discussion
1. Estuarine Environment and Coastal Fish Resources.
2. Length of coastline and surface of mangrove for the countries of
Southeast Asia.
3. The dependence of coastal resources on estuarine and mangrove
environment
4. Estuarine Fish Ecology and Rehabilitation.
5. Economic Significance of Changes in the Fishery Assemblages.

12. 1.Estuarine Environment and Coastal Fish
Resources
Three major factors can explain this nursery role:
1. Trophic resources,
2. Water turbidity,
3. Structural diversity.

13. 2.Length of coastline and surface of mangrove for the
countries of Southeast Asia
Country Coastline (km) Surface of mangrove
(km2)
Indonesia 54,716 45,421
Malaysia 4,675 6,424
Philippine 36,289 2321
Singapore 193 56
Thailand 3,219 2,641
Vietnam 3,444 2,723

14. 3.The dependence of coastal resources on
estuarine and mangrove environment
Example:
According to McHugh (1976) for instance, in 1961, 97% of the fish
biomass harvested by the US in this zone was of species living a part of
their life in estuaries; 1961 and 1971, 90% of the fish biomass
harvested in the Gulf of Mexico was estuarine-dependant. On a wider
scale, Houde and Rutherford (1993) calculated that estuarine-
dependant resources made up 50% of the total US commercial landings
in 1990.

15. 4.Estuarine Fish Ecology and Rehabilitation
The main features of estuarine fish communities in tropical
environments similar to those of Southeast Asia can be summarised as
follows:
The assemblage of continental origin
The estuarine assemblage
The coastal assemblage

16. Contd.
The different types of rehabilitation actions have been summarised
below under the following headings:
Coastal rehabilitation,
Modification of river hydrology,
And pollution mitigation

17. Contd.

18. 5.Economic Significance of Changes in the Fishery
Assemblages
Global estimates
Estimates based on specific assemblages
Valuation of biodiversity

19. Conclusions
This study indicates the lack of well established quantified relationships
between fish yields and area of mangrove. This concern could be
addressed in Southeast Asia by a detailed analysis of capture data as a
function of mangrove area in different countries, taking full account of
the spatial and historic variations in fishing effort.

20. Thank You