South-East Asia's Environmental Future: The Search for Sustainability (1993): Part III - Selected issues: Change and the environment: 12. Coastal, inshore and marine problems: South-east Asia

South-East Asia's Environmental Future: The Search for Sustainability (1993)

Foreword

Preface

Acknowledgements

Abbreviations and glossary

Notes on contributors

Part I - The driving forces of change

Introduction

1. The dimensions of environmental change and management in the south-east Asian region

(introductory text)

Introduction

Trends of the mid-1970s to 1980s

Some explanatory variables

Projecting trends into the future

The conditions of resource management in the region

The main environmental issues

The need for a new concept of common resources

2. Population growth in south-east Asia: Pushing the limits

(introductory text)

Introduction

The population situation

Population growth and the environment

The future

3. Industrialization and urbanization in south-east Asia

(introductory text)

Trends in economic growth, 1961-1987

Structural change

Factors responsible for strong ASEAN growth

Trends in urbanization

Urban primacy and megacity issues

Levers to influence urbanization and urban structure

Conclusion

Development problems and the environment

4. Energy and mineral development: Environment and economics

(introductory text)

Introduction

Global economic development: energy and minerals

Environment and resource attributes of south-east Asia

Energy and mineral demand in the Asia-pacific region

Assessing environmental costs

Non-conventional and alternative energy and minerals

Economic development, environment and the future

Summary and conclusions

Editorial comment

5. The onslaught on the forests in south-east Asia

(introductory text)

The nature of the forest resource

Deforestation and forest degradation: Apportioning blame

Managing the forest: The role of government in land-use planning

Rebuilding the forests

The future of the forests

Notes on co-operative management

In defence of south-east Asia

(introductory text)

Editorial comment

Part II - Climatic change and variability

Introduction

6. Climate model predictions for the south-east Asian region

(introductory text)

Human-induced climatic change

Predicted climatic changes: The global view

Climate model predictions and the south-east Asian region

Uncertainties and unknowns

Climatic change and public policy

7. Enso, drought and flooding rain in south-east Asia

(introductory text)

Introduction

The El Niño-southern oscillation

ENSO and south-east Asia

Effects of ENSO on climate

Impacts of ENSO

ENSO in the past and future

Future work

A successful prediction using unconventional data

(introductory text)

Prediction of the 1991 ENSO event in Indonesia

Editorial comment

8. Climatic change and agriculture: Problems for the Asian tropics

(introductory text)

Climatic change in tropical Asia, 1910s-1980s

Problems in climate-agriculture relationships: Rice yields in three areas

Flow of impacts of climatic change on agriculture

Concluding remarks

Climatic change in Indonesia

(introductory text)

Introduction

The ongoing indonesian climatic change

Possible impact on rice

Editorial comment

Part III - Selected issues: Change and the environment

Introduction

9. Sustaining and expanding the 'green revolution' in rice

(introductory text)

An overview of the 'green revolution' in south-east Asia, 1970-1989

Problems of the green revolution

Areas for future endeavour

Ecological policies for sustaining high production in rice: Observations on rice intensification in Indonesia

(introductory text)

Introduction

An outline of Indonesia's achievements in the green revolution

The problems of expanding production in Indonesia

Assessing the yield potential of the green revolution

Diminishing biotic diversity and increasing vulnerability

Facing the problems of sustainability

Rice production and sustainability in the 1990s

Editorial comment

10. The problems of upland land management

(introductory text)

Introduction

The expansion and intensification of upland agriculture, 1850-1950

Upland agriculture, 1950-1990: Logging, roads, markets and cash

The environmental consequences of upland agricultural expansion: Sustainability and unsustainability

Attempted solutions

What is to be done?

Pitfalls of the intensification debate

Immediate needs in upland Java

(introductory text)

Editorial comment

11. The hazard of fire

(introductory text)

Introduction

Losses and impairments due to fire

Factors promoting the spread of fire

Reducing the incidence of large-scale fire

A wider view of the fire hazard

The need for management

(introductory text)

Editorial comment

12. Coastal, inshore and marine problems

(introductory text)

Introduction

Global trends

South-east Asia

The future

The south-east Asian response

(introductory text)

Aspects of the physical setting

National and international responses

Editorial comment

Part IV - Selected issues: places and people

Introduction

13. Threatened places

Natural and human hazards

(introductory text)

Introduction

Nature's threats

Human threats

Natural hazards and their management

Conclusion

The tragedy of the open access

(introductory text)

Introduction

Forest management in Nepal

Managing forest resources in Indonesia

Managing forest resources in Thailand and the Philippines

Management of marine resources

Discussion of common property management

Threatened places: A regional view

(introductory text)

Hazards and response

Traditional resource management

Editorial comment

14. On threatened peoples

(introductory text)

Introduction

Threatened peoples: Contrasts in composition and environment

Tribal peoples of south-east Asia: Causes and nature of threat

The indigenous socio-economic system: Is it sustainable?

The penan and the timber blockade

Responses to the problems of the threatened peoples of south-east Asia

Conclusion

Sustainability of indigenous socio-economic systems

(introductory text)

Editorial comment

15. Urban environmental issues in south-east Asian cities: An overview

(introductory text)

Introduction

Major causes of urban environmental degradation

State of urban environments in south-east Asia

Managing the urban environment: Some possibilities

Concluding remarks

Editorial comment

Part V - Conclusions and recommendations

16. Conclusions and recommendations

(introductory text)

A set of concerned conclusions

Recommendations for research and future action

The search for sustainability

Bibliography

South-east Asia

South-east Asia

As a parallel activity to the GESAMP global review, regional assessments were made. Gomez et al. (1990) prepared a report which covers the seas bordering the Association of South-East Asian Nations (ASEAN) and Hong Kong. The working group was composed of representatives of each country concerned. Another useful reference on the marine environment of the region appeared in 1988. The journal of the Royal Swedish Academy of Sciences, Ambio, published a special issue (Volume 17, Number 3) on the East Asian seas. An overview of the region's environmental problems (E. D. Gomez, 1988) was followed by articles on specific topics by different authors.

As mentioned above, the problems of the marine environment are more pronounced in marginal seas than in the open ocean. The seas of South-East Asia may be characterized as marginal. In the early 1990s, the Indonesian and Philippine archipelagos are inhabited by 250 million people, most of whom live in the coastal zone. The populations of the other ASEAN countries contribute another one-third of this number, in addition to those of the Indo-Chinese peninsula. The total population of South-East Asia in 1990 was placed at 440.8 million (WRI, 1990).

With population pressure exerting itself heavily in the coastal areas, there is great concern about habitat destruction. Among the most heavily affected are mangrove forests, the largest of which are in Indonesia. Big coastal areas in the more populous islands have been converted into fish and prawn ponds, with only the narrowest of mangrove strips remaining on the seaward side. Of about 2.5 million hectares of mangroves, some 700000 hectares were converted to various uses between 1969 and 1979. It is feared that an equivalent area will be destroyed before the end of the twentieth century. Malaysia ranks second in total mangrove area. Fortunately, of the more than 0.5 million hectares of mangrove coastline, perhaps less than 20 per cent have been converted to other land uses. The situation in the Philippines has been less positive. Of some 400000 hectares, only about 25 per cent remain. In the other countries, the position is not as bad. but all are threatened.

The coral reefs of South-East Asia are also under attack, although for a different reason. There is limited direct use of reefs except locally for mining lime. It is in the process of extracting fish and other marine products that the coral reef:s themselves are often negatively impacted. Illegal methods such as dynamite fishing have become widespread in the region. Overfishing of reefs has begun in many areas, whether it be for fish, invertebrates or seaweeds. A more serious threat in many regions, and particularly in the Philippines, is siltation resulting from the erosion of coastal areas due to deforestation and poor land-development practices. The Philippines provides one example of what can happen to coral reefs. E. D. Gomez (1989) presented a summary of their condition. Fully 70 per cent are in a poor-to-fair condition with less than 50 per cent live coral cover. The situation in the other countries is probably not much better.

The over-exploitation of fish stocks is becoming more evident. Any review of the fisheries of the region will show the drastic drop of stocks in the Gulf of Thailand in the 1960s. Later studies in the Philippines have revealed that demersal stocks and those of small pelagics have begun to decline. If long-term monitoring were undertaken, the trends could be documented in the various countries.

An equally severe problem, because of the sheer numbers of people in the coastal zone, is the organic pollution entering the sea. Most of this pollution is in the form of sewage, much of which is discharged untreated into rivers and coastal water bodies. To this is added the litter and other solid wastes that are so characteristic of areas near populated parts of the region, with the possible exception of Singapore. The amount of organic load in the coastal waters is becoming heavier. In some estuaries and embayments, eutrophication is increasingly evident as well as microbial contamination. More alarming, however, is the growing frequency of red tides, or paralytic shellfish poisoning in the region. The few occurrences in the mid-1970s became more frequent in the following decade; in the Philippines, eight cases were reported (Corrales and Gomez, 1990). The start of the 1990s is witnessing a further escalation of this trend.

In spite of the exploitation of oil and the large volume of oil shipping passing through the various straits of South-East Asia, pollution has not been out of proportion. The proceedings of a workshop held in Bali provides a review of the oil pollution in the region (Yap, de la Paz and McManus, 1988). Gomez et al. ( 1990) also contains a section on oil.

This review would not be complete without touching on mining activities affecting the marine environment. In addition to oil (2 million barrels per day) and gas (5 billion cubic feet per day), much of which is from offshore wells, there are tin-dredging operations that have caused problems in coastal areas, particularly in Thailand. In a few celebrated cases in the Philippines, the problem of disposing of copper-mine tailings into coastal waters has become prominent. Fortunately, these are not widespread.

Manila Bay

A few of the environmental problems of the Philippine marine waters and coastal ecosystems have already been mentioned in general terms. It would be well to illustrate on a finer scale some of the problems related to coastal waters adjacent to large population centres. For this purpose, Manila Bay can be used, as it may in some ways be compared with the Upper Gulf of Thailand, where the Chao Phraya River debouches after passing through Bangkok, and also with Jakarta Bay in northern Java.

Manila Bay is a semi-enclosed body of water comparable in size to the Upper Gulf of Thailand but with a narrow sill that connects it to the South China Sea. While several rivers empty into the bay, the two most prominent are the Pampanga River to the north, which drains a large agricultural region, and the Pasig River to the east, which, in addition to agricultural runoff, carries with it industrial and municipal effluents from the Metro Manila area. The more significant input of pollutants into the bay comes from the large metropolis, whose population is now in the order of eight million. Only a small fraction of the households in the greater Manila area are sewered.

Studies on marine pollution in the Philippines were reviewed by Deocadiz ( 1990), who indicated that Manila Bay is contaminated with pesticides, industrial wastes and oil, in addition to domestic wastes. While earlier studies tended to show rather high values of heavy metals, which may have been artefacts of the analytical methods used, later studies (for example, Soria and Theede, 1990) indicate only a mild contamination of Manila Bay by heavy metals. In sharp contrast, Acorda ( 1990) indicated that bacteriological pollution has been on the increase, to the extent that the waters of eastern Manila Bay have been declared unsafe for bathing. This bacteriological pollution is no doubt due to the high input of raw sewage into the bay. It is suspected that the organic pollution in the bay has contributed to the increasing frequency of red tides as mentioned earlier.