Hydrobiologia 285: 139-150, 1994. A. Sasekumar, N. Marshall & D. J. Macintosh (eds), Ecology and Conservation of Southeast Asian Marine and Freshwater Environments including Wetlands. © 1994 Kluwer Academic Publishers. Printed in Belgium.

139

Marine environmental issues of Southeast Asia: state and development L. M. Chou Department of Zoology, National University of Singapore, Singapore 0511, Republic of Singapore

Key words: marine, environment, management, resources, development, protection

Abstract The seas of Southeast Asia play an important role in the economy of the surrounding countries. The region's constantly expanding coastal population and development has made great demands on marine resources, with growing evidence seen in the further degradation of the marine environment and continued exploitation of living as well as non-living resources. Integrated coastal area management has never been considered in the past while environmental protection measures and policies have largely been at local or national levels. Implementation of regional study programmes less than 10 years ago and ratification of international as well as regional agreements aimed at protecting the marine environment in recent times indicate a more enlightened approach to the problem.

Introduction

Physical setting

The seas of Southeast Asia surround land masses which support intense as well as rapidly increasing coastal development. The expanding population of the region also places a growing demand on living and non-living resources, with marine resources playing a major role. The pace of coastal zone development and marine resource utilization has in many cases, resulted in the degradation of the marine and coastal environment. Management plans for such areas were non-existent or dismissed by policy makers as impractical and a hindrance to development and national economic growth. More recently, there has been a realisation of the long-term benefits of coastal and marine environment management strategies. This paper provides an overview of the state and development of the marine environment in Southeast Asia.

Southeast Asian seas stretch over a wide geographical area of 9 million km 2 , or 2.5 percent of the earth's ocean surface (Fig. 1). Filled with islands of varying size, they form the link between the Pacific and Indian oceans, separate the continents of Asia and Australia, and are characterised by high diversity habitats favoured by the tropical climate and heavy precipitation that transport nutrients from land to sea. Indonesia and the Philippines, the two largest island archipelagos in the world, have more than 20000 islands combined. Almost all the Southeast Asian countries have extensive coastlines and numerous offshore islands, most of which are coral or volcanic islands. The total length of coastline is 92451 km (Table 1) providing a variety of coastal and nearshore marine ecosystems which is recognised as being greater in Southeast Asia than in other parts of the Indian Ocean

140

Fig. 1. The seas of Southeast Asia. Table 1. Estimated coastline length of the Southeast Asian countries (World Resources Institute, 1992). Country

Coastline extent (km)

Brunei Darussalam Cambodia Indonesia Malaysia Myanmar Philippines Singapore Thailand Vietnam Total

161 443 54716 4675 3060 22540 193 3219 3444 92451

region (IUCN/UNEP, 1985a). The seas are characterised by both, extensive shallow continental shelves and deep basins, trenches and troughs.

The physical oceanographic features of the region have been adequately described by Wyrtki (1961) and Soegiarto (1981). The tropical waters experience little change in surface temperature and moderate tidal variation. Currents can be strong, however, in many areas they reverse their direction under the strong influence of the seasonal monsoons and therefore do not effectively flush pollutants out to the oceans. The monsoons give the area definite wet and dry seasons. Soegiarto (1985) describes the Southeast Asian waters as being ideal for the study of monsoonal effects on water circulation and also on the seasonal variation in the physical, chemical and biological properties. Stratification of the water column occurs in some of the deeper seas but over most of the Sunda and Sahul shelves, the temperature

141 remains uniform throughout the water column. Salinity is variable and lowered in nearshore areas, particularly after heavy rainfall. Bays and channels with restricted circulation also tend to have lowered salinity. Nutrient load in coastal and nearshore waters is high because of river outflows, and while the average surface primary productivity based on limited data indicate low production rates of 1 g C m- 3 h - ' in the open sea, higher rates are obtainable in coastal waters (Soegiarto, 1985). The river outflows contribute to the high level of silt in coastal waters. Nutrient levels are increased during the monsoons. In offshore waters, the surface layers have low nutrient levels (phosphate content of 0.2 ppm), while the deeper layers have greater nutrient content (3 ppm). In the tropics, nutrients remain trapped in the deeper layers unlike the temperate seas where annual turnover due to seasonal climate variation brings up bottom nutrients. In tropical open seas, nutrients are brought to the surface by upwelling or divergent water movements at the surface, which are usually localised or seasonal.

Population growth and urbanisation

Table 3. Urban population as a percentage of total population in Southeast Asian countries (World Resources Institute, 1992). Country

Cambodia Indonesia Laos Malaysia Myanmar Philippines Singapore Thailand Vietnam

Urban population % of total population 1960

1990

10.3 14.6 7.9 25.2 19.3 30.3 100.0 12.5 14.7

11.6 30.5 18.6 43.0 24.8 42.6 100.0 22.6 21.9

since 1950 and it is projected to grow a further 63 % (724 million) by the year 2025. Growth rate remains high in spite of a slower increase compared to the 1960s and 1970s. A population shift towards urban centres is apparent (Table 3). Most of the region's main cities and towns are located within the coastal zone, and over 70% of the region's population is estimated to be presently concentrated in coastal settlements. The continued expansion of the coastal population places a heavy strain on the coastal and marine environment and their resources.

The region's current population of 444 million (Table 2), represents an increase of over 1400% Living marine resources Table 2. Population and growth in the Southeast Asian countries (World Resources Institute, 1992; Kuntjoro, 1987; UNEP, 1987). Country

Brunei Darussalam Cambodia Indonesia Laos Malaysia Myanmar Philippines Singapore Thailand Vietnam

Population (millions) 1950

1990

2025

0.14 (1971) 4.4 79.5 1.8 6.1 17.8 21.0 1.0 20.0 30.0

0.22 (1985) 8.3 184.3 4.1 17.9 41.7 62.4 2.7 55.7 66.7

14.0 285.9 8.6 30.1 72.6 111.5 3.3 80.9 117.5

The wide variation of geomorphological features together with the physico-chemical, oceanographic and climatic conditions make the region's seas highly productive and supportive of rich and extensive marine habitats, and is recognised as the faunistic center for the entire Indo-Pacific (IUCN/UNEP, 1985b).

Coral reefs Southeast Asian seas contain 25 to 30% of the estimated 600 000 sq. km of coral reefs worldwide (Smith, 1978). All the morphological reef types are represented and coral diversity remains high

142 with almost all the known extant coral genera present (Gomez, 1988). The most extensive reefs occur in Indonesia and the Philippines. Diversity of reef fishes and reef-associated organisms is also high. The reef supports both resident and visiting fish species, and is valuable for artisanal and commercial fisheries. Coral reefs can potentially supply 12 % of the world's fish catch (Munro & Williams, 1985). In Sabah, East Malaysia, reef fishes make up 25% of total fish catch (Mathias & Langham, 1978). An estimate of 25% has also been reported for the Philippines (Carpenter, 1977). In Trengganu, West Malaysia, the figure reaches 30% during certain months (De Silva & Rahman, 1982). Apart from fish, other major biological groups of the reef which provide a source of food include molluscs, crustaceans, echinoderms and seaweed (McManus, 1988). Reef resources are also exploited for uses other than food. The marine curio trade removes shells and coral, while the aquarium trade demands fish and other invertebrates. Most are exported to countries beyond Southeast Asia. Coral and limestone blocks make excellent building and construction materials. Increasing attention has been focused in recent years on the reef ecosystem as a rich source of natural bioactive substances. The region's high biodiversity reefs, with many species still undiscovered, are an enormous potential source of pharmaceutically important products. Coral reefs are also valuable in their natural role as breakwaters while the breakdown of the limestone framework provides a source of sand for beaches. The visual impact and colourful splendor of reefs make them important as a natural resource for tourism and when properly managed and developed can provide employment and an effective source of revenue. Rates of primary production on reefs are high (Lewis, 1981), although that of the surrounding waters are low. This is due to the complex but efficient recycling of material within the reef community and to its ability to fix atmospheric nitrogen (Longhurst & Pauly, 1987), thus making them comparable to the tropical rainforest ecosystem. The region's coral reefs are being impacted by

growing and diverse human influence. Excessive harvesting of edible fish, shellfish and other reefrelated organisms for food has led to rapid depletion of stocks. The marine curio and aquarium trades have had devasting impacts on the ecosystem (Wood & Wells, 1988). The fast removal of target species has affected the ecological balance of many reefs permanently. Giant clams for example, have been depleted from many reefs. Destructive fishing methods such as the muro-ami, blasting, poisoning are detrimental to the ecosystem. Coral mining weakens the framework of reefs and the activity also destroys live corals and other organisms overlying the limestone foundation. Mining of buried fossil giant clam shells in Indonesia is also damaging. Man's activities on land, such as deforestation, mining and reclamation, increase the sediment level in the sea which in turn affects coral-growth by direct smothering or reducing light penetration. Sedimentation resulting from coastal and marine tin mining in Phuket has affected the reefs there (Chansang, 1988). Extensive land reclamation in Singapore since 1963 has affected the deeper zones of reef slopes (Chou, 1988). Some countries in the region are beginning to recognise the importance of this ecosystem and have designated reefs as marine reserves in order to prevent the further degradation and loss of this valuable resource.

Fisheries Fish forms the major source of protein in the region and there is a heavy dependence on the sea for this resource. Per capita consumption of fish in the Asean countries is high (Table 4), forming over half of all animal protein consumed. Table 5 shows annual marine catch amounting to almost 8 million tonnes from the region's seas in the late 1980s, representing a significant increase over the late 1970s. Pauly & Chua (1988) pointed out that annual marine catch in the six Asean countries increased almost fourfold from 1.5 million tons in the early 1960s to 5.5 million tons in the early 1980s. The

143 Table 4. Fisheries consumption in the ASEAN countries (Kent & Valencia, 1985; World Resources Institute, 1992). Country

Per capita consumption (kg/yr)

Brunei Darussalam Indonesia Malaysia Philippines Singapore Thailand

24.1 14.0 30.1 33.8 39.6 20.8

value of fishcatch in Southeast Asia amounts to 3 % of the gross national product of these countries, which is greater than the 1% in most developed countries throughout the world (Kent & Valencia, 1985). Most of the catch within the region consists of demersal species, caught by artisanal as well as commercial fishermen. Indications are that the fisheries stocks in the region have been overfished. In the Gulf of Thailand and west coast of southern Thailand, fish stocks have been exploited at a level of 40 % above the maximum sustainable yield (Arbhabhirama etal., 1987). In the Philippines, demersal and small pelagic fisheries have been declining since the mid 1970s due to excessive effort. In Indonesia, trawling has been banned since 1980 (Sardjono, 1980). The problem appears to have been aggravated not only by the rapid increase in catch in the 1960s and 1970s, but also by serious Table 5. Average annual marine catch in the Southeast Asian countries (World Resources Institute, 1992). Country

Mangroves Southeast Asian mangroves represent more than 30% of the world's mangroves and are the most diverse in species composition. Almost half of the 40 tree species have commercial importance (Hundloe & Boto, 1990). The areal extent of mangroves in the Asean countries cover over 50000 km 2 (Table 6). Their direct value comes from the traditional use of mangrove wood for fuel and building materials. The bark is used for the production of tannin while some species have edible leaves or fruit (IUCN/UNEP, 1985a & b). Mangrove trees are also used in the production of chipboard and Saenger et al. (1983) identifies many other uses of the mangrove ecosystem in the region. The indirect value of mangrove ecosystems lies in their role of sustaining other natural resources such as fish, crustacea and shellfish, and they have been shown to support nearshore fish production (MacNae, 1974; Unar & Naamin, 1984).

Average annual marine catch 1987-89 (thousand metric tons)

Brunei Darussalam Cambodia Indonesia 1971 Malaysia Myanmar Philippines Singapore Thailand Vietnam

degradation, and in some cases loss, of the marine environment brought about by a rapid increase in coastal populations and development (Pauly & Chua, 1988). Pauly (1989) points out that classical fisheries development methods using incentives such as soft loans, tax rebates, etc. can no longer be applied as the fisheries resources of the region have already been overfished.

3 6.5 60 598.6 552.5 1478.1 14.7 2629 620.8

Percentage change over 1977-79 73

Table 6. Areal extent of mangroves in the Asean countries (Sources: Darsidi 1984, Aksornkoae 1986, Chan 1986, Corlett 1986, Tech. Staff, Philippine National Mangrove Committee 1986, Zamora 1987). Country

Area (km 2)

Brunei Darussalam Indonesia Malaysia Philippines Singapore Thailand TOTAL

184 42510 6288 878 5 2873 52738

- 34 - 10

40 25 -5 35 51

144 In Indonesia alone, the value of mangrove forestry products both for export and domestic use, amounted to an estimated US$26 million in 1978 while mangrove-linked fisheries amounted to US$194 million (Salm & Halim, 1984). Chong et al. (1990) showed that tropical mangroves were more important as feeding grounds than as nursery grounds for juveniles of commercially important fish species. Their study also confirmed that mangroves were important nursery areas for commercially important prawn species. Mangrove forests are also important in protecting shorelines against erosion and modifying the effects of typhoons on coastal areas. They trap sediment washed down by rivers and restrict freshwater runoff from land so the salinity of the coastal area remains stabilised. The region's mangroves support a high diversity of over 300 plant species and more than 1000 marine invertebrate and vertebrate species, in addition to 177 bird and 36 mammal species associated with mangroves. Some of these, like the proboscis monkey, Nasalis larvatus, of Borneo are of scientific interest. While a better scientific understanding of the full potential of the mangrove ecosystem is required to enable a proper valuation of the resource, non-sustainable exploitation and destruction are occurring at an accelerating pace in the region (Paw & Chua, 1991). Population growth has increased the pressure on mangroves for fuel and building materials. Mangrove related fisheries are being rapidly exploited. The ever increasing demand on mangroves for timber, chipboard and paper has led to large scale deforestation of the resource. Policy makers have long regarded mangroves as wasteland that encourages the breeding of mosquitoes and have cleared extensive areas for agriculture, aquaculture, as well as residential and commercial development. In the Philippines, the extent of the mangrove ecosystem was reduced by about 65 % from 418 990 ha in 1967 to 146 139 ha in 1978 (NEPC, 1980). Between 1969 and 1979, 700000 ha in Indonesia was cleared for agriculture (Soegiarto, 1980). Development in Singapore has reduced the extent of mangroves from 10 to 12% of total land area

150 years ago to an estimated 1% in 1980 (Chou et al., 1980). Seagrasses The valuable role of the region's seagrass ecosystem is already recognised. Seagrasses thrive in shallow waters and are known to be widespread and with a high biodiversity (Fortes, 1988). However, data on the extent of this ecosystem in the region remain limited (Fortes, 1989). The major economic importance of seagrass beds stems from their provision of critical nursery grounds for many commercial species of fishes and shrimps (IUCN/UNEP, 1985b). The ecosystem, with its high primary productivity, supports large invertebrate and fish stocks in surrounding areas. Genera of commercial importance which are dependent on seagrass beds for some stage of their life history include Penaeus, Lutjanus, Lethrinus, and Siganus. Seagrasses also form the major source of food for dugongs, green turtles and juvenile hawksbill turtles, all of which are of interest from the scientific or conservation point of view. The economic value of the fishery associated with a seagrass ecosystem in Tarut Bay, Saudi Arabia, has been estimated to be US$8 million. If the seagrasses were consumed directly by green turtles, the turtle yield would be US$46 million (Basson etal., 1977). Fortes (1989) provided a review of economic valuations of seagrassassociated fisheries. These values although theoretical, provide an indication of the importance of the resource. The indirect value of the ecosystem is usually ignored. These communities bind sediments, reduce turbidity, retard erosion and lower levels of pollution. Little attention has been paid to the importance of the seagrass ecosystem. A high percentage has been affected by industrial, agricultural and sewage discharge, coastal reclamation and dredging, and overfishing. Destruction of this ecosystem has been known to cause the collapse of the shrimp fishery in some parts of the world while overfishing leads to changes in the ecosystem, often resulting in population explosions of other

145 species such as sea urchins which eventually destroy the natural balance (Stauffer, 1937; Rasmussen, 1977; Stoner, 1980).

Soft bottom habitats and rocky shores Soft bottom habitats consist of two categories, open and enclosed. The open habitats include inshore shallow seabed areas of sand and silt as well as the sandy and sand-mud beaches on exposed shores. Throughout the region, sand and clay predominate, influenced by river inputs. There is a higher biodiversity and greater biomass of flora and fauna on these shallow seabeds than on deeper offshore seafloor. Molluscs and echinoderms are usually associated with these shallow soft bottom areas which serve as significant fishing grounds suitable for trawling. Stocks of a wide variety of fish species and shrimps are available. The sandy shores, themselves with limited flora and fauna, are important as nesting grounds to turtles. The main threats to these habitats are beach sand mining and overfishing of stocks. Development of beaches for recreational use which occurs throughout the region is so intensive in some areas that it places additional stress on the environment. Enclosed soft bottom habitats include lagoons, mudflats, bays and estuaries. These are widespread in the region, and are extremely productive when they support mangrove and seagrass communities. Mudflats with their covering film of microalgae and are highly productive. They are usually associated with river mouths and the nutrient-rich organic sediments support the growth of benthic organisms. The estuarine areas of the region support major fisheries, and mudflats are used throughout the region for the culture of the blood cockle, Anadaragranosa,which forms a significant industry. Coastal lagoons are converted for the aquaculture of milkfish (Chanos chanos), tilapia (Oreochromis spp.) and catfish (Puntiusjavanicus).These habitats are often subjected to heavy pollution because of the natural convergence of human populations to the vicinity of major rivers.

Rocky shore habitat is widespread in the region and range from limestone to volacanic rocks. They support a high diversity of life. The upper intertidal zone is dominated by barnacles, limpets, nerites and oysters throughout the region. Corals are usually associated with the lower intertidal and subtidal zones, where abalones and spiny lobsters also occur. Commercial fish species include serranids, lutjanids, lethrinids and breams. This habitat appears to have been less exploited.

Non-living marine resources Hydrocarbons Some areas of the region's seas contain rich deposits of petroleum and related products (Valencia, 1983) which contribute to the economy, particularly of Brunei Darussalam, Malaysia, Indonesia and Thailand. A large source of petroleum and gas reserves along the Sunda shelf remains untapped (Bilal, 1985). This resource in the Asean region currently amounts to 3.5% of total crude oil production and 2.5% of natural gas production worldwide. Offshore production of crude oil increased from 20% to 50% in 1980, and offshore exploration is expected to increase and extend further into deeper waters. In the extraction of offshore crude, precautions to prevent pollutive damage to the marine environment are being taken but accidental spills and blowouts have occurred from time to time. Fisheries resources and ecosystems such as mangroves, coral reefs and estuaries are particularly vulnerable to oil spills. Drilling operations themselves tend to increase the sedimentation levels of the surrounding waters.

Minerals Submarine tin deposits up to depths of 65 m can be exploited but cost considerations and presentstate technology have so far confined mining activities to nearshore waters. Silica sand and iron

146 sand deposits occur throughout the region and continue to be exploited. Mining of these minerals in the sea involves dredging and disposal of tailings, and results in increased siltation of the waters. This in turn decreases marine primary productivity which in turn decreases fishery potential. Coral reefs are particularly susceptible to high siltation rates, and the decreased clarity of water affects marine-related tourism and recreation. Sediment budget changes around the area being mined can alter coastal geomorphology, as well as affect power plant cooling. Coastal activities such as mariculture can also be seriously affected. Pollution caused by such mining has occurred in various locations of the region, notably the Strait of Malacca and around Phuket.

Marine pollution Marine pollution levels are higher in the coastal waters than the open seas. This issue is of great environmental concern, particularly with the continuing trend of increasing coastal population. Fast growing coastal cities in the region, many without adequate sewage treatment plants contribute to the degradation of coastal waters and shallow marine habitats. Open drainage canals keep pouring raw effluents and industrial wastes directly into coastal waters. The majority of Southeast Asian rivers are so polluted with wastes, including raw sewage, that they are considered biologically dead. Case studies of coastal pollution throughout the region have been highlighted by Hinrichsen (1990). One of the problems concerning marine pollution in the region is the lack of reliable long-term data (Gomez, 1988). Hungspreugs (1988) gives an overview of the status of heavy metals and other non-oil pollutants in the region. Existing information on heavy metals in seawater remains insufficient. Heavy metal levels in benthic sediments appear to indicate high contamination of some parameters within localised areas around high density coastal settlements. Hydrocarbon contaminants have also been detected in benthic sediment of harbours and estuaries. Chlorinated

hydrocarbons, used as pesticides in agriculture have also been detected in the coastal environment but not at alarming levels. Red tides, both toxic and non-toxic, caused by blooms of dinoflagellates have been increasing in frequency and locality within the region (Maclean, 1989). Although the causative factors have not been positively identified, pollution from landbased sources is strongly suspected. The occurrence of red tides has an impact on the mariculture industry as it usually results in fishkills of immense proportions. Paralytic shellfish poisoning caused by ingestion of fish and shellfish during red tide blooms have resulted in fatalities throughout the region and is of growing concern. The discharge of raw sewage into coastal waters has raised the coliform count to beyond acceptable limits. Shellfish in these areas usually have high coliform counts in their tissues. This increases the risk of exposure to human pathogens and disease transmission.

Degradation of the marine environment The factors contributing to the degradation of the marine environment have been identified to be mostly human activities (Gomez et al., 1990; GESAMP, 1990). Rapid development of the coastal zone and population growth have resulted in the present situation. The uncontrolled exploitation of living marine resources sometimes using destructive methods has led to the loss of habitats and species. Many of these living resources are being removed at a rate far exceeding the natural sustainable levels. With non-living resources, the extraction process itself causes environmental degradation. Nearshore mining activities have often contributed to erosion of beaches and loss of reef habitat due to sedimentation. Coastal waters have been subjected to pollution through the discharge of urban and industrial wastes. To support the physical growth of coastal cities, reclamation of foreshore areas and changes in the coastal geomorphology by man-made construction are common. These changes have caused further impact on the ma-

147 rine environment by altering current patterns and increasing the sediment load particularly when water circulation of the area becomes reduced. An economic assessment of logging versus fisheries and tourism in Palawan, Philippines (Hodgson & Dixon, 1988), showed that the loss in benefits from fisheries and tourism due to sedimentation caused by logging, far outweighed the benefits generated from logging. Southeast Asian seas contain some of the most intensively used shipping routes. Marine transport plays an important role in the region. A large volume of oil is transported through the region each day. Bilal (1985) estimated that 3.8 million barrels per day leaves the region while another 3 million barrels pass through the Strait of Malacca en route to Japan. Such large volumes being transported daily poses a high risk of accidental spills. The 1975 grounding of the Showa Maru in Singapore Strait resulted in the largest oil spill incident in the region. Mangroves in the surrounding Indonesian islands which were seriously affected showed no sign of recovery or regeneration 3 years after the spill (Soegiarto & Polunin, 1981). Oil discharge also comes from normal shipping operations such as loading, bunkering and deballasting. Adding to the problem is the spillage from small craft which discharge oily bilge waters. The transport of hazardous substances is another risk factor that needs to be considered. Accidents of this nature at sea however have so far been uncommon. Gomez et al. (1990) reported three incidents in the Philippines. In 1977, 350 tonnes of sulphuric acid were lost at sea and in two separate incidents in 1978, 500 tonnes of caustic soda spilled from a sinking barge and 20 000 bags of fertilizer were lost from a vessel hit by a typhoon.

Environmental cost Environmental degradation has led to loss of living resources and critical habitats. Although difficult to quantify it is evident that the cost can be enormous. Some indication is provided by the cost of cleaning up oil spills. A 50-tonne oil spill

off the recreational east coast of Singapore in 1988 cost US$200000 in cleaning up operations alone. Malaysia spent US$1 million to clean up the Diego Silang oil spill in the Strait of Malacca. These costs do not take into consideration environmental damage in terms of loss of living resources and critical habitat, as well as loss of earnings by fishermen and loss of revenue from tourism (for recreational areas). Habitat restoration efforts are also costly. The Singapore River and Kallang Basin were cleaned and restored to a non-polluted condition in a 10-year US$150 million programme. At Pattaya, Thailand, the unrestrained growth of beach facilities has resulted in severe deterioration of coastal water quality which now requires millions of dollars for restoration. It is obvious that restoration of degraded habitats is expensive in terms of direct costs. When seen as a total of other related or implied costs, it appears appropriate that protective measures or policies on sustainable development be given serious consideration, since it makes more economic sense in the long term.

Environmental protection measures and policies Many Southeast Asian countries have become aware of the environmental cost of marine pollution and habitat degradation and are beginning to focus attention on the management of coastal and marine development, as well as on the restoration of degraded habitats and denuded resources. Examples demonstrating this trend are the 1989 Langkawi Declaration on the Environment issued by the Commonwealth heads of government, the 1990 Baguio Resolution on Coastal Resources Management issued by the Policy Conference on Managing ASEAN's Coastal Resources for Sustainable Development, and the 1991 Singapore Resolution on Waste Management issued by the Conference on Waste Management in the Coastal Areas of the ASEAN Region. In order to conserve genetic resources and biodiversity, governments are beginning to establish more nature reserves and protected areas,

148 many of which include the marine environment. Most of these however, still have a long way to go in terms of effective management and enforcement. Some management plans fail especially when they do not take into consideration the needs of traditional users. Others fail because of strong pressure from the commercial sector or weak political will. Many of the countries are 'caught in a trap of debt and development' (Hinrichsen, 1990). More resources have to be exploited to pay interest on growing debts. In 1988, 28% of Philippine's export income went towards servicing debts. Many of the countries need to balance the growing needs of an increasing population against declining resources. World trade is forcing developing nations to export more of their natural resources in order to meet national development goals. Planners and economists have to face the challenging task of effecting sustainable development for long term gain. Some of these measures appear to have worked in small villages where community-based conservation measures have been implemented to maintain living marine resources at sustainable levels. At Apo island in the Philippines, the local fishing community was shown that the destructive fishing methods which they were using were destroying the reefs and causing fish stocks to decline. They have now implemented certain conservation measures and are enforcing them as a community. This includes the assertion of their rights over the reefs of the island and the prevention of fishing by people of other communities. More attention is being given to habitat enhancement as a means of increasing productivity and biodiversity. Artificial reefs have been established in all the Asean countries, some at community levels while others at national levels. Results appear to be encouraging but more studies are required to determine their effectiveness in contributing to biomass increase, instead of simply aggregating fish from the vicinity. Experiments using artificial seagrass are also being conducted in the region. In recent years, more projects of a regional nature have been implemented to deal with the marine environment. The Asean-USAID project

on 'Coastal Resources Management' examined selected coastal sites within the Asean countries in order to prepare coastal zone management plans for them which would serve as models for the region. The Asean-Australia project on 'Coastal Living Resources' provided valuable data on the state and development of coral reefs, mangroves and soft-bottom communities, and is now examining the inter-relationships between them. The Asean-Australia 'Tides and Tidal Phenomena' project also provided information on oceanic current patterns and tidal levels and is presently continuing as the 'Regional Ocean Dynamics' project. An Asean-Canada project is investigating the establishment of environmental criteria for the development and management of living marine resources and human health. The East Asian Seas Action Plan initiated by the United Nations Environment Programme was adopted in 1981 by the governments of Indonesia, Malaysia, Philippines, Singapore and Thailand. The plan provided a means by which the countries may deal with common marine resource problems. A more recent issue fast gaining interest is global climate change and the associated sea-level rise. The implications on the marine and coastal environment in the region is being examined by a task team within the East Asian Seas Action Plan. The information being obtained from the results of these regional projects is useful in the planning of long-term management strategies to slow down the further degradation of the marine environment and irreversible decline of the resources. An integrated approach will be important as this open-access resource is utilized by various sectors of the community. Reducing the level of conflict between these sectors will help to achieve the goal of sustainable development. References Aksornkoae, S., 1986. Thailand. In Mangroves of Asia and the Pacific: Status and Management. Technical Report of the UNDP/UNESCO Research and Training Pilot Programme on Mangrove Ecosystems in Asia and the Pacific (RAS/79/002): 231-261. Arbhabhirama, A., D. Phantumvanit, J. Elkington &

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