Tài liệu STRATEGIC ENVIRONMENTAL ASSESSMENT on shrimp farms in the southeast of Thailand docx

Minor Field Studies No. 176

_______________________________________________________________________

Swedish University of Agricultural Sciences

International Office

Uppsala, November, 2001

ISSN 1402-3237

STRATEGIC ENVIRONMENTAL ASSESSMENT

on shrimp farms in the southeast of Thailand

Teresia Lindberg and Anna Nylander

Supervisor in Sweden:

Hans-Georg Wallentinus, Associate Professor and Director of the EIA Center, SLU,

Department of Landscape Planning Ultuna, Uppsala

Supervisor in Thailand:

Magnus Torell, Project leader at ICLARM

The Minor Field Studies series is published by the International Office of the Swedish

University of Agricultural Sciences.

Minor Field Studies are carried out within the framework of the Minor Field Studies

(MFS) Scholarship Programme, which is funded by the Swedish International

Development Cooperation Agency (Sida).

The MFS Scholarship Programme offers Swedish university students an opportunity to

undertake two months´ field work in a developing country to be analysed, compiled

and published as an in-depth study or graduation thesis work. The studies are primarily

made on subjects of importance from a development perspective and in a country

supported by Swedish development assistance.

The main purposes of the MFS programme are to increase interest in developing

countries and to enhance Swedish university students´ knowledge and understanding of

these countries and their problems and opportunities. An MFS should provide the

student with initial experience of conditions in such a country. A further purpose is to

widen the Swedish human resource base for international development cooperation.

The International Office of the Swedish University of Agricultural Sciences

administers the MFS programme for the rural development and natural resources

management sectors.

The responsibility for the accuracy of information presented rests entirely with the

respective author. The views expressed are those of the authors and not necessarily

those of the International Office.

Swedish University of Agricultural Sciences

International Office

Box 7070

SE-750 07 UPPSALA

Sweden

Telephone: +46 18 672309

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Tryck: SLU/Repro, Uppsala 2001

Preface

This Minor Field Study (MFS) was performed by Teresia Lindberg and Anna Nylander, who

are both studying Eco-toxicology at Uppsala University in Sweden. The report is a Master´s

thesis for Teresia Lindberg.

The Swedish International Development Agency (Sida) finances a number of so-called Minor

Field Studies for students or young people to carry out a research project in a developing

country. The study usually takes place in one of Sida´s target countries and is part of a local

Sida-sponsored aid programme. The study was located on the south east coast of Thailand

with the Coastal Resources Institute (CORIN) at the Prince of Songkhla University in Hat Yai

as a study centre. The field work was carried out from the end of February until the end of

April, 2001.

A number of people have been a great help for us during our study. We would first like to

thank our supervisor Hans-Georg Wallentinus at the Department of Landscape Planning

Ultuna, SLU for help and support and Magnus Torell at ICLARM for providing us with very

useful contacts in Thailand.

At CORIN in Hat Yai we would like to thank Somsak Boromthanarat and Ayut Nissapa for

letting us work at their office and for helping us with contacts.

We would also like to express our gratitude to Siri Tookwinas at the Department of Fisheries

in Bangkok, Noparat Bamroongrugsa at the Prince of Songkhla University, Putth

Songsangjinda at the Department of Fisheries in Songkhla, Max Andersen at DANCED

(Danish Co-operation for Environment and Development) in Ranod and Jim Enright at The

Mangrove Action Project in Trang for assistance during our field study. A special

appreciation to Simon Funge-Smith at FAO in Bangkok who has been a tremendously good

source of information both in Thailand and when questions turned up in Sweden.

Sara Gräslund at the Institute of Applied Environmental Research at the Stockholm

University and Johan Sundberg at Sida have provided us with informative material.

Last, but not least our sincere thanks to all helpful and friendly Thai people and especially the

shrimp farmers.

Abstract

This Strategic Environmental Assessment was carried out in order to collect up-to-date

material about the situation of the coastal shrimp farming industry in the south east of

Thailand and to compare different shrimp farming methods. The semi-closed intensive shrimp

farming system, which is the most commonly applied farming method in Thailand, is

compared with a closed farming system where the water is recirculated and a system where

the sludge is removed on a regular basis. The study was performed in five provinces on the

southeast coast of Thailand where, during the spring of 2001, the authors interviewed shrimp

farmers as well as expertise at Departments, University institutions and Environmental

organisations.

The black tiger shrimp dominates the Thai production and about 90% of the cultivated

shrimps are exported for luxury consumption in industrialised countries. Marine shrimp

farming has expanded greatly during recent decades and can today be found in every coastal

province of the country. The intensive farms have been constructed by converting a variety of

land uses, including former extensive shrimp farms, mangroves, rice paddies and other

plantations.

The environmental and socio-economic impacts of the different shrimp farming systems are

described in the report and the alternatives are evaluated and compared with each other with

reference to the different impacts. The main environmental impacts are due to chemical use,

mangrove destruction, salinisation, eutrophication, sedimentation, extraction of ground water

and spread of diseases and genes. The socio-economic impacts are, for example, health

problems, loss of livelihood and fresh water resources, impacts on agriculture, marginalisation

and changes in employment.

According to the comparison, it is apparent that the semi-closed system has the most negative

environmental and socio-economic impacts. Both the closed recirculating system and the

sludge removal system have less negative impacts on the environment and on the social and

economic systems than the semi-closed farming system. Concerning mangrove forest

destruction, extraction of ground water and loss of mangrove values and products, the

alternatives give no impact at all.

The closed recirculating system is considered to be the most sustainable alternative due to the

many issues where no negative impacts occur. This is only true providing that the system is

successful despite some managerial problems. If the system should not work entirely, the

sludge removal system or a closed recirculating system without waste water recirculation are

still much more sustainable alternatives than the semi-closed farming systems that are used in

Thailand presently.

The major problems connected to the two alternative methods described in this report are the

high construction and operation costs. It is not realistic to expect a poor farmer to adopt one of

the alternative systems described in this report without external economic support. A

reasonable possibility for a farmer could be to continually invest in more sustainable methods.

Keywords: Shrimp farming, aquaculture, ecotoxicology, strategic environmental assessment,

environmental impacts, socio-economic impacts, intensive shrimp farming, chemicals,

mangrove forest, Thailand.

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1. INTRODUCTION .................................................................................................... 4

1.1 Objectives............................................................................................................................ 4

1.2 Methodology ....................................................................................................................... 4

2. SCOPE................................................................................................................... 5

3. DEFINITIONS AND GLOSSARY ........................................................................... 7

4. HISTORY.............................................................................................................. 11

5. PRESENT STATUS OF SHRIMP FARMING IN THAILAND ............................... 13

6. ENVIRONMENTAL SETTINGS ........................................................................... 16

6.1 Black tiger shrimp (Penaeus monodon).......................................................................... 16

6.2 The natural cycle of shrimp development...................................................................... 16

6.3 The mangrove forest ........................................................................................................ 16

6.4 Hatcheries ......................................................................................................................... 18

6.5 Grow-out techniques ........................................................................................................ 19

6.6 Inland shrimp farming..................................................................................................... 21

6.7 Production process and water treatment....................................................................... 21

6.8 Diseases of cultured black tiger shrimp ......................................................................... 23

6.9 Artificial shrimp feed....................................................................................................... 24

6.10 Chemicals and biological products ............................................................................... 25

7. DESCRIPTION OF THE ALTERNATIVES........................................................... 28

7.1 Zero alternative: Semi-closed intensive system ............................................................. 28

7.2 Alternative 1: Closed recirculating system .................................................................... 29

7.3 Alternative 2: Sludge removal system ............................................................................ 30

8. ENVIRONMENTAL IMPACTS ............................................................................. 31

8.1 Mangrove deforestation................................................................................................... 31

8.2 Physical barriers............................................................................................................... 32

2

8.3 Pollution by chemicals and water treatment products ................................................. 33

8.4 Sedimentation ................................................................................................................... 34

8.5 Salinisation and the extraction of groundwater ............................................................ 35

8.6 Eutrophication and water quality issues........................................................................ 37

8.7 Energy usage..................................................................................................................... 39

8.8 Diseases and genetic pollution......................................................................................... 40

8.9 Trawling for wild brood stock and for fish meal........................................................... 41

8.10 Decreased need for trawling wild shrimp .................................................................... 42

9. SOCIO-ECONOMIC IMPACTS ............................................................................ 43

9.1 Land conversion and loss of livelihood........................................................................... 43

9.2 Employment and inequity ............................................................................................... 44

9.3 Public health problems .................................................................................................... 45

9.4 Impacts on the agriculture .............................................................................................. 47

9.5 National versus local economy ........................................................................................ 48

10. EVALUATION OF THE ALTERNATIVES.......................................................... 50

10.1 Evaluation of the alternatives concerning environmental impacts ........................... 50

10.2 Evaluation of the alternatives concerning socio-economic impacts........................... 52

11. CONCLUSION AND DISCUSSION.................................................................... 55

12. MITIGATION ...................................................................................................... 57

13. SUSTAINABILITY ISSUES................................................................................ 62

14. UNCERTAINTIES............................................................................................... 65

15. REFERENCES ................................................................................................... 66

APPENDIX 1. GOVERNMENT REGULATIONS AND PLANNING ......................... 72

APPENDIX 2. CHEMICALS COMMONLY USED IN THAILAND ............................ 76

3

APPENDIX 3. DIRECT AND INDIRECT PRODUCTS FROM THE MANGROVE

FOREST................................................................................................................... 78

4

1. Introduction

1.1 Objectives

The aim of this study was to collect up-to-date material about the situation of the shrimp

farming industry in the southeast of Thailand and to compare the most common shrimp

farming method in Thailand with two other, hopefully more sustainable, methods. This was

done by making a Strategic Environmental Assessment (SEA). The reason for this study was

to assist the Swedish International Development Cooperation Agency, Sida, in their

investigation of possible future support to shrimp farming.

The present work is part of a larger study on shrimp farming, which is being performed by the

EIA-centre at SLU on behalf of Sida. One of the goals with this study is to be able to set up a

checklist for review of Environmental Impact Assessments (EIAs), including SEAs, for

shrimp farming. EIAs are always needed in project proposals, which are submitted to Sida for

assessment. Both the Rio Declaration and the Agenda 21 emphasise the importance of using

EIAs in development co-operation.

A purpose of this SEA is to add to Sida´s EIA-handbook. The report can hopefully also be

used to facilitate and improve the EIA-process for project directors and consultants.

1.2 Methodology

The study includes interviews with shrimp farmers and with expertise at Departments,

University institutions and Environmental organisations. Employees at feed processing

factories and independent researchers were also interviewed. Most of the shrimp farms were

family-owned, but some were big shrimp farming companies such as Chareon Pokphand

(CP-company) or research farms like the DANCED funded shrimp farm in Ranod and the

Department of Fisheries shrimp farm in Songkhla. Field observations and literature studies

were also performed in this study.

The material is summarised and compared in a Strategic Environmental Assessment (SEA).

This report is a back-casting SEA, which means that it investigates the impacts of already

existing shrimp farms.

Environmental Impact Assessment (EIA) is a process that examines the environmental

consequences of development actions in advance. EIA is also a document that should describe

and compare different alternatives. The zero-alternative, which describes the situation

providing that nothing changes in the future, should be included in the comparison. An EIA

shall take into consideration direct or indirect effects on:

• People, flora and fauna

• Land, water, air, climate and landscape

• Material assets and cultural heritage

• Interaction between the above-mentioned factors

The assessment how a project relates to environmentally sustainable development should be

performed in a holistic perspective. Therefore, equally environmental, health-related, social

and economic aspects should be considered.