COMMUNICATIONS

ENVIRONMENTAL PLANNING FOR AQUACULTURE DEVELOPMENT :
INTEGRATING AQUACULTURE IN COASTAL ZONES ¹

BY Dr James F MUIR,
Scotland

¹ The following text is based partially on, and quotes extensively form “Environmental management of aquaculture development” draft report for TCP/CYP/9152 by J F Muir and D J Baird, December 1991. I am grateful to the Government of Cyprus and to FAO for the opportunity to develop this and related material

1 Background; the case for environmental planning

1.1 Introduction

The Mediterranean region has a long history of involvement with human society, culture and economy, and has had to absorb a wide range of human influence, in the form of settlement, land-use, trade and communication. The more modern transformations of urbanisation and intensification have also come about, with their concentration of resources, energy and wastes (see eg. Grenon and Batisse, 1989 - the Blue Plan). There is increasing pressure on resource use through population growth and economic activity, whether in the form of primary production, manufacturing, or the increasing tertiary level service sectors. The region also has important terrestrial and aquatic habitats, and the high quality of Mediterranean areas in aspects such as history, culture, landscape and environment is particularly important with respect to tourist and residential development, above all around the coastal margins of the basin. The sea itself has always played an important part in the region, both in supplying fish and other aquatic products, and in supporting trade and cultural communication between the different peoples of the region.

Aquaculture contributes a growing part of the fishery sector within the Mediterranean (see, eg Charbonnier, 1989). The newer and more intensive forms of aquaculture which are increasingly common in the region overlie a number of traditional or established practices which have evolved and become accepted within the regional landscape, and in some cases may even enjoy special and protected status. Newer aquaculture systems may be more intrusive however, and may be seen to demand resources and practices which are not traditionally provide. Now, however, even the older forms of aquaculture are changing quite rapidly, in response to changes in resource availability, economic demand, and technical inputs. The region can, therefore, already count on a large and diversified production base, but one which may be expected to move significantly in coming years, both in response to market directions, and to deal with the increasing restrictions facing any resource-sensitive form of primary production.

1.2 The need for environmental planning

Stimulated by scientific and technical progress, local and region development support, and by prospects of market price and profitability, aquaculture in the Mediterranean has expanded significantly over recent years.

It is moving from extensive semi-national methods in traditional areas based on lagoons, shellfish beds and ponds, towards modern intensive approaches using ponds, tanks, raceways, cages and longlines, in which many new areas and environments are becoming involved (see eg ADCP 1989). Such is the pace of development and of evolution of new techniques, and such are the economic consequence of success or failure, that structures of planning and development, and the legal and instutional framework in which they exist, may be inadequate for responding to the needs of the sector, or for creating and maintaining an appropriate climate for support resource allocation, management and control.

The Mediterranean region provides a range of climatic regimes and aquatic ecosystems. To be effective and ‘sustainable’, production systems must operate within these ecosystems and within the biological and ecological constraints of the stock produced. Consequently it is the direct interest of the producer to be environmentally protective. Nonetheless, justifiably or otherwise, the environmental impact of aquaculture is causing increasing concern. Fears are expressed over matters such as effects on predators and others adjacent species, possible genetic contamination of wild stocks, and the impacts of waste nutrients. While much of this concern might be allayed by well-considered planning and by responsible management practices, this is an area which may be subject to extremes of public opinion. Although there may be little basis on scientific grounds for immediate concern about the effects of current or prospective aquaculture development, the environments concerned - sensitive both ecologically and politically, may require particular care in their management.

The experimental and relatively small-scale nature of most aquaculture activity has permited, even favoured a liberal development approach, with few restrictions and considerable financial and technical support. However the emerging size of the industry and the scale of its individual production units, raise questions concerning physical and economic development, resources demands and environmental protection. While there are definite and possibly significant prospects for expanding aquaculture, development will have to come about within increasing resource constraints, and against competition from other sectors, many of which may be better established within the economic and political framework. In line with local and international understanding and concern, such development would also become subject to increasing and more stringent environmental scrutiny.

These issues, therefore, require an informed and responsive system of planning and management, to protect the environment, other users of resources, and interests of the public, and to ensure efficient longer-term development of the industry. Any proposal for planning and management for a sector such as aquaculture, which involves basic resources such as land water, and which impinges on so many other different areas and activities, will also need to be made part of an integrated and cross-sectoral approach, is based on concepts such as integrated land the management, on watershed management, and on coastal area management.

2 Environmental issues in the planning process

2.1 Introduction

Development over the last two decades has resulted in a viable but as yet (in relative terms) small-scale industry, which may face significant expansion, particularly into marine aquaculture in coastal and offshore areas. Although aquaculture has not developed in as significant or diversified a manner as other food production sectors, there are similar issues to be resolved. So far the industry has been usually regulated on an ad hoc basis, without overall longer-term planning and development. While this approach has at least been workable, it may not be feasible if a larger and more environmentally dominating industry develops. Elements of control and good practice must be enforced, but it may be necessary to simplify and standardise the processes of planning, approval and monitoring. Good planning can define and provide for the overall context for growth, but care will be required to find the correct balance between development opportunity and regulation.

Environmental planning in the Mediterranean has come into particular focus in Cyprus, where aquaculture was blamed for a troublesome spread of filamentous algae which caused disturbance to coastal areas and major concern for tourist interests. The problem was if anything more probably a response to the enrichment of coastal waters from intensive agriculture and domestic wastes-not least the tourist establishments themselves. However, such was the public concern that aquaculture was placed under an effective moratorium. More disturbing perhaps than the problem and the debate it created was the realisation that the existing system has few mechanisms for assessing the situation and acting appropriately on the evidence available, and that many far more serious issues might be obscured from public awareness and excused from political action.

This problem is not unique (see eg Garvey and Bennet, 1991), and the rise of aquaculture as a new and apparently demanding user of aquatic resources has highlighted in many countries the absence of appropriate planning frameworks (see eg Van Houtte et al, 1989). The environmental impacts of coastal aquaculture have recently been addressed at the international level by GESAMP (1991), from whose approach the following principles-widened to embrace fresh water aquaculture-can be derived:

-   (coastal aquaculture has the potential to produce food and to generate income contributing to social and economic well-being;

-   planned and properly managed aquaculture development is a productive use (of the coastal zone) if undertaken within the broader framework of integrate (coastal zone) management plans, according to national goals for sustainable development and in harmony with international obligations.

-   the likely consequences of (coastal) aquaculture development on the social and ecological environment must be predicted and evaluated, and measures formulated in order to contain them within acceptable, predetermined limits;

-   (coastal) aquaculture activity must be regulated and monitored to ensure that impacts remain within predetermined limits and to signal when contingency and other plans need to be brought into effect to reverse any trends leading towards unacceptable environmental consequences.

2.2 Required actions

A set of specific actions consequent on these principles was also identified (GESAMP, op cit), of which the following (grouped together, and again slightly adapted for the complete aquaculture sector) may be relevant to the regional situation:

-   formulate (coastal) aquaculture development and management plans, to be integrated into overall (coastal zone) management plans; formulate integrated (coastal zone) mana gement plans;

-   assess the capacity of the ecosystem to sustain aquaculture development with minimal ecological change; apply the environmental impact assessment (EIA) process to all major aquaculture proposals; select suitable sites for (coastal) aquaculture; monitor for ecological change.

-   regulate discharges from land based aquaculture through the enforcement of effluent standards; apply incentives and deterrents to reduce environmental degradation from aquaculture activities; improve the management of aquaculture operations; establish guidelines for the use of bioactive compounds in aquaculture;

In order to set the scene for incorporating them into a planning and regulatory approach for aquaculture development and environmental management, the following areas would normally have to be considered further;

-   the national resource base; physical, environmental and social; their characteristrics and appropriateness for needs and consequences of aquaculture; sustainability and environmental acceptability with respect to economic development; the availability of resources and/or resilience of environments potentially affected by aquaculture activities.

-   The national institutional context; the institutional structure and the legal and other support framework available, and its appropriateness and relevance to the needs for support and/or control of the sector.

-   objectives of national plans; the implications of these given the resources requirements and the physical, economic, social and environmental characteristics of the aquaculture sector; approaches in complementary or competitive sectors, and the positioning of aquaculture amongst these in a rational and equitable manner;

-   the regional context; ie issues of production, markets and competition, regional environ mental and aquaculture development policy andplanning, and the structures available or envisaged for regional coordination and support;

3 Aquaculture systems and their relationships

3.1 Introduction

The relationship between aquaculture and competing users of resources rests fundamentally on the nature and quality of resources demanded. This section reviews aquaculture systems in this respect, particularly in terms of land and water resources. Two fundamental types of system can be used for aquaculture production:

-   land-based, in which production units are installed in fixed positions on land, with water supplies provided to them, and;

-   Water-based, in which structures are set up within defined bodies of water.

Each type involves different considerations for siting, construction, operation and management.

3.2 System choices

Although the range of systems, species and techniques used is very large, for any given set of circumstances the range of options will quickly be narrowed by a small number of major constraints. The use of a particular species may define the types of system suitable (eg due environmental) or feeding requirements, or market value), which will in turn define the sites required. A certain site will define which systems are feasible to establish, which will in turn suggest particular species. A particular system will support certain species and require particular sites.

Although there might be infinite combinations of these main elements, certain quite clear relationships exist between them which serve to narrow down the possibilities, allowing the developer to concentrate on ensuring that species, system and sits match satisfactorily. A successful combination of these elements will do much to ensure viability. In general, systems are defined according to two main criteria;

-   the type of system; ie ponds, lagoons, tanks, raceways, cages, enclosures, rafts*, ropes*, trestles* etc. (*for molluscs)

-   the intensity of production; typically described as extensive, semi-intensive, intensive, etc.

Thus characteristics of marine aquaculture systems are given in Table 1. In selecting an appropriate system for a particular set of circumstances, the developer will need to assess the importance of each factor and put a weighting on it. Thus if water area is in short supply, a system requiring less water area is a major consideration. If there is a shortage of skills, a less complex design may be important. The system employed will clearly have a bearing on capital and operating requirements, and hence the costs, of a project. Thus for the same quantity of product using different intensity of production, the capital and operating inputs vary substantially. It is this variation in characteristics which makes it so important to select systems appropriate to the sites and resources available.

Table 1: Aquaculture systems; outline design characteristics

4 Land resources

4-1 Introduction

Land use will depend on the type of system involved, its intensity and whether it is substantially land or water-based. Other important aspects include the layout and efficiency of use of land-related to topography and design, and the quality of land, and hence its specific usage within a site. Even with water-based form of aquaculture there are some requirements, eg for service bases, access, etc. For a more complete perspective on land use, the following may be considered:

-   land requirements for actual development, including access, protection areas, non-productive areas (eg pond walls) - accounting/planning aspects are discussed later;

-   effects on surrounding land, which although not directly used may be impacted by the presence of aquaculture;

-   ‘ghost land’ ie the land resources involved in supplying necessary inputs-eg feed materials, seed, services, etc for aquaculture production - important in overall resource planning;

-   opportunity costs of land use in terms of foregone alternative uses (see economics section later)

For land-based systems, use can be estimated directly from productivity intensity figures-thus at 2 tonnes/ha/yr, an annual production of 100 tonnes would require a nominal (100/2) = 50ha. In practice, however, at least 10% and up to 30–40% would be added to this for roadways, walls, service areas, protection belts and landscaping etc. In the case of water-based systems, though most of the space occupied in production is associated with a particular water body, with the exception of fully self-contained ship or barge-based systems, land is usually required for service, access and operational buildings. In some cases, accommodation will also be required. For production of up to 100–200 tonnes, at least 0.5 ha is usually needed, and this will increase for larger systems.

As Table 2 suggests, intensity and land use also has implication for development costs, as structures, pond walls and other structures will vary in number, cost, complexity with the type of system employed. This in turn will interact with questions such as the costs of the land in determining the approach to be employed.

Table 2: Demonstration of the implications of intensity of production

Note : where * is shown, capital inputs described are unlikely to be found in normal uses.

The assessment of land quality, particularly soils, is a very important aspect of land use, site selection, development and management. This is particular the case in pond farms, where soil quality has a great influence on construction and maintenance costs, and on pond productivity, but would also be important in selecting sites and developing designs for tank, cage, enclosure and lagoon farms, and for components such as water supply channels, building foundations, and river or coastal protection structures.

4.2 The effects of land use

Although it is often claimed that aquaculture is particularly suited to poor quality land, unused or marginally useful for agricultural production, this is not necessarily the case. Most freshwater pond farms in the tropics are built on arable land, although marginal areas may sometimes be used, particularly where land is in short supply. In communities where fish farming is firmly established, areas of arable land involved can be substantial; Among rice growers in Central Luzon, philipines, for example, an average of 20%of farm areas is devoted to rice-fish culture (Tagarino 1985). In the philippines and Indonesia and elsewhere productive rice fields have been converted to fish ponds. In Taiwan, estimated that land devoted to aquaculture doubled between 1965 and 1985 to 70,000 ha (Lee 1987), with major impact on land utilisation. Whilst in several prefectures - Kaohsiung and pingtung-much land either marginal or unsuitable for agriculture, some change in use of prime agricultural land undoubtedly occurred.
Of particular concern is the extent to which aquaculture has developed in land area which is not important for agriculture, but has cirtical ecosystem value - eg salt-marshes, wetlands, mangrove systems-commonly the highly productive and complex water-land interface areas. In parts of SE Asia, substantial areas of mangrove land has been converted to aquaculture, with extensive destruction of habitat, effects on nursery grounds, destabilisation of soils, etc. Although measures are now being taken to reduce effects - shelter belts, reseeding, use of pumped sites, etc, many '000s of hectares have already been affected.

Aquaculture has been involved in land use conflict in several parts of the tropics, particularly in highly urbanised or overcrowded areas. In Singapore and Hong Kong shortages of land have adversely affected production of fish for the aquarium trade (Tan and Siow 1989) whilst in China, shortages of land near reservoirs has led to development of water-based «cove culture» for fish fingerlings for restocking (Lu 1986). In Bangladesh, eg Sundarbans, Khulna, competing land use between shrimp farming and seasonal rice, vegetable production; salinised soils have reduced land capability, important effect on lower-income households.

Water-based aquaculture does not use land but it does occupy areas of lakes and rivers, and this can result in copetition for resources similar in many respects to the competition for land. The best-known example is that of the pen culture industry in Laguna Lake, philippines in which rapid and uncontrolled expansion during the late 1970s and early 1980s resulted in an area of some 35,000ha, equivalent to more than one-third of its surface area, being occupied by milkfish (Chanos chanos) pens (Beveridge 1984). Access to fishing grounds and navigation routes used by lakeshore communities was severely disrupted, thus causing a great deal of social tension. The presence of the fish-pens in the shallow inshore areas were also believed to have disrupted fish spawning and nursery grounds, thereby depressing fisheries yields.

There may be less concern for land use for freshwater aquaculture, as much land used for ponds is agricultural and, unlike coastal aquaculture, little evidence of large areas of other types of land being converted to freshwater fish production. Moreover, intensification of production is apparent in many parts of the tropics such as Taiwan, where production rose from an average of 1.4t ha-1 to 3.6t ha-1 between 1965 and 1985 (Lee 1987). However, changes in land use are not irrevisible, being principally determined by economics (Hanning 1988). In Israel, for example, the area of land devoted to fish farming fell by 20% from 3,529 ha to 2,818 ha between 1979 and 1988 despite massive increases in production (Sarig 1989). Cages and pens are more temporary in nature and can and have been readily dismantled as economic and political situations change (Beveridge 1984, 1987).

Other points to consider include:-

-   effects of land clearance, disruption of vegetation cover, stability of soils, access to forage crops

-   albedo effects, change in reflection/absorption characteristics, temperatures, hence air and water movements, effects on vegetation-localised effects but may also affect eg coastal plains;

-   siltation, effects on water courses, also protection eg from coastal movements, erosion etc.

-   effects on traditional landuse, access, foraging, grazing temporary settlements;

4.3 Ghost land requirements

Based on concepts of total land to supply resources; becomes particularly revealing for land-use planning, assessment of intensive systems; eg if I ha pond uses 3 tonnes of grain in fish production, which in turn has required 1.5 ha of land for production, total land requirement for stock production is 2.5 ha. In practice this can be complicated, though standard factors now available for converting resource inputs into equivalent land areas (including even fish inputs).

4.4 Opportunity cost implication

Some of the main opportunity cost aspects for aquaculture land include alternative uses for;

-   coastal land for tourism, residential areas; usually very high value, also intolerant of aquaculture developments;

-   mangrove and marsh lands for ecosystem value, but how to put a value on this? See later environmental economics.

-   reservoir area and upland river valleys for agriculture, forestry, other upland activities; water use usually valued, often provides main decision point rather than land.

-   lower river valleys, floodplains for agriculture, commerce; in populated areas, serviced land of this type becomes more and more valuable for housing, light industry, intensive agriculture/market gardening.

4.5 Land-use planning

One of the first approaches may be establish an ‘Aquaculture land-use Inventory’, to define the extent to which land is used, the types of land involved, and the implications for and of development. processes such as GIS analysis (see next) may help to define location priorities and highlight potential conflict, provided aquaculture needs can be sensitively enough defined.

Also need to develop effective means for integrating aquaculture demands with others, and preferably reach approaches for ‘integrated land and water use management’ eg in which aquaculture can place complementary and positive role rather than negative and depleting role. Thus examples of:

-   land reclamation in integrated projects, eg Sundarbans, Lower Mekong delta, in which aquaculture provide economic ‘engine’ for diversified development, holds back exploitative use locally, encourages settlements;

-   Role in water retention, storage and land stabilisation, eg with hillside reservoirs, storage ponds, freshwater retention after monsoons in saline areas drinking areas for animals, subsidiary water supply for humans;

-   Role in sanitation, public health, waste treatment, safe use of farm and domestic wastes;

-   Use in silt retention as temprary phase prior to land reclamation in stabilising downstream landforms;

-   Use in integrated coastal management, funding protection works, water controls;

5 Water use

5.1 Introduction

Aquaculture is a net consumer of water and most forms require considerable quantities. Stocks require oxygen, and water, naturally and/or artificially oxygenated, is the only source, except for eg Ophicephalus (Channa) spp .and Clarias spp. Which may be grown in anaerobic ponds, by switching to air breathing in the absence of dissolved oxygen (Muir 1981; Bevan 1986).

Dissolved oxygen depends on the amount of entering the system, and/or processes within the system itself-depends highly on system design.

-   Intensive systems; short water residence times rely heavily on inflowing water, carrying capacity determined largely by respiratory requirements of stock and tolerance to low dissolved oxygen, relative to supply in inflowing water (Haskell 1955; Shepherd and Bromage 1987; Fivelstad 1988).

-   Water supply contributes less in systems with long water residence times, such as extensive or semi-intensive ponds, where internal processes such as phytoplankton photosynthesis and mixing (Boyd 1982) are more important.

Water resource availability is a key factor in determining where aquaculture may develop. The World water resources can be roughly divided into freshwater and marine resources (Table 10a.1). production statistics vs resource volume demonstrates low utilization of marine resources. In theory freshwater aquaculture may use water at almost any stage in hydrological cycle; in practice, surface waters, only 0.3% of resources, most commonly used. Much water abstracted from rivers or streams though some already used for irrigation. Groundwater considerably more abundant; though sometimes locally important, used less globally (Phillips et al 1990)

5.2 Water demands

Surveys of water demand show extreme variability, eg seven European countries reported by Alabaster (1982) Unfortunately, difficult to assess the reasons for this variability without more detailed information in fish production and management techniques. Results of a more detailed analysis shown in Table 3, shows quantities used per tonne of production vary enormously, as determined not only by seepage and evaporation but also by intensity of production (i.e stocking density and the use of feeds and fertilisers) and management.

Lowest requirements for air breathing walking catfish Clarias batrachus in Thailand. Above this, various tropical and subtropical pond systems have comparatively low unit water demand. Highest demands for salmonids (and carp) in intensive flowthrough, with water used as sole input to supply oxygen and remove metabolites. Krom et al(1989) attempted to categories systems by flow regimes. Low flow, extensive or semi-intensive types - water added to counteract evaporative and seepage losses, predominate in tropics. Seepage varies at least a factor of 10 up to 2.5cm day-1, depending on soil type and pond surface area (Boyd 1979). Evaporative losses may be as great as 2.5cm day-1, though in sub-tropics more typically around 0.5 cm day-1 (Huet 1972, Hepher and pruginin 1981, Teichert-coddington et al 1988). If total losses of 1–2 cm day-1 typical if tropics, each ha pond will consume 100–200m3 water per day. Total requirement for ponds estimated by Hepher and pruginin (!981) to vary between 35 and 60,000 m3 ha-ly-1 to maintain average depth 1.5 m throughout the growing season (240 days), counteract losses estimated at between 1 and 2 cm day-1.

Intensive production of species tolerating poor water quality (e.g. catfish) possible with little increased water use (Colman 1990). Intensification usually requires more use to maintain water quality (Krom et al 1989). Intensive, high flow-rate freshwater systems to occur but rare in tropics. Such systems open (flow-through) or closed (some recycling). Most in urban area or where water is scarce (Hepher 1985, van Rjin et al 1986, Krom et al 1989). High water use where water plentiful and/or no laws or costs to restrict use. In EIFAC survey, European freshwater farms, water consumption per tonne varied more than 100-fold (Alabaster 1982). Where conservation of water us necessary or desirable, some sort of cost penalty may need to be enforced. Intensification has resulted in different approaches - in most species (Salmonids, channel catfish and shrimps) accompanied by increased water use. In contrast, intensification of common carp and tilapia culture in Israel has resulted in a decrease in water requirements (Hepher 1985; Sarig 1988a), primarily because of the high cost of water in Israeli aquaculture (17.5–21.3% of production costs. Sarig 1988b) and priority being given to water conservation.

Table 3 Water requirements per tonne of aquaculture production.

The very high water requirement of salmonid culture in part explained by sensitivity to poor water quality and need to maintain high dissolved oxygen and low metabolites. However large differences between these flow-through systems and other pond systems suggests that water quality control within pond system (production of oxygen and assimilation of metabolites) is major factor improving water use efficiency.

5.3 Value and demand

Compared with other industries, aquaculture has a very high water demand, except for the atypical Clarias systems in Thailand. Aquaculture also adds fairly little value to water resources, thus it may have a low priority when in competition with other industrial or agricultural resource users with similar requirements.

Value vs pollution may also be high in comparison with other industries, further justifying consideration of aquatic resource use for aquaculture (Muir and Beveridge 1987). These analyses argue for integration of aquaculture with other industries or agriculture. There may however be positive effects, eg for aquaculture to add value to a water resource, eg fish production in sewage fed ponds to improve water quality and generate income from a waste material (Edwards et al. 1987; Little and Muir 1987). Researchers in Scandinavia are also attempting to improve water quality in acidified freshwater lakes through selective pollution by cage culture (Solbe 1987).

Table 3a Typical water requirement of industry and agriculture in comparison with selected aquaculture systems. Figures for water requirement of pork and beef production refer to the total water requirement (i.e., feed plus drinking water). (Modified from schwab et al. 1971 and Muir and Beveridge 1987).

Table 4 : Production loading from aquaculture and other industrial and agricultural sources.
(Source: Muir and Beveridge 1987).

5.4. Effects of water demand

Abstraction may adversely affect conditions in surface waters by:

-   changing channel shape and patterns of sedimentation, affecting siltation and water movement;

-   reducing spawning or nursery areas for fish stocks;

-   causing barriers to migratory fishes;

-   altering thermal regimes;

-   altering biological communities through loss of dilution capacity between inflow and outflow.

A major impact is that on water quality, as discussed elsewhere; also have an adverse impact on the environment, with water being lost or temporarily diverted from the catchment area. Loss of water resources through transfer of between different stages of the hydrological cycle. Transfer/recharge of groundwater to surfacewater can result in loss or resources, with consequences for other groundwater uses and land resources. Eg groundwater for penaeid shrimp culture resulted in salinisation of groundwater and surrounding land and subsidence of coastal land by up to 3m in some parts of Taiwan (Chien et al.1988)

Evaporation (and lesser extent transpiration) may be significant loss. Evaporation occurs at all waterair interfaces, dependent on water and air temperatures, relative humidity of the air and wind velocity. Although evaporation will occur in all facilities, only likely to be a significant in ponds with long retention times. Losses from open water varies from 0–0.8 cm/day in Europe to 2.5 cm/day or more in tropical regions (Huet 1970).

Seepage; transfer from surface water to groundwater, proportional to soil porosity and may be significant in earthen ponds-varies from 0.01–0.66 cm/day (Hepher and Pruginin 1981;Boyd 1985). Combined seepage/evaporation losses significant in long retention time ponds (up to 100% in seasonal rainfed), may have significant impact on resources where pond culture is extensive.

Fast flowing intensive systems, low evaporation and seepage losses but severe impacts may arise as a result of abstraction and temporary diversion of surface water. Localised depletion may result in reduced flow in irrigation canals, rivers or streams, impacts on indigenous fisheries (paticularly migratory), potable other industrial or agricultural water supplies and recreational water users (Alabaster 1982). Conflicts between aquaculturists, eg for irrigation canal water supplies for penaeid shrimp culture (ASEAN 1978). May become acute where demands greatest at times of minimum water (e.g. Atlantic salmon smolt farming in Scotland)

5.5 Resource allocation and potential conflict

Use for aquaculture often regulated either specifically or as part of the right for fishing or agricultural purposes (Van Houtte et al 1989); in practice few constraints. Where water is scarce conflicts can arise, eg Israel, where water has to be paid for, many cases more profitable to use water for crop irrigation than aquaculture, Fish ponds have been destroyed or deepened to from irrigation or dual purpose fish culture/irrigation reservoirs and fish culture restricted to only part of the year (Hepher 1985, Milstein et al 1989a 1989b).

Until late 1960's, Taiwan's aquaculture based heavily on traditional chinese fresh and brackish water, integrated polyculture systems. Due to successful industrial development, consumer buying power increased, bringing changes to the fish market, move away from quantity systems, producing carp and milkfish to more intensive systems producing quality species like eel, grouper, and shrimp. Aquaculture based on small family units, 1–3ha, passed on from generation to generation. Shortage and very high cost of land have meant most culture systems have intensified, requiring constant care and attention 24 hours a day, 7 days a week-uneconomic if families were not involved and paid labour bad to be hired.

In 1981 aquaculture consumed 11% of Taiwan's total consumption, which amounts to some 21 million MI, most drawn from shallow boreholes, usually about 8m deep, where unpolluted and temperature stable water (25–26 C) all year round. During last 5 years often uncontrolled development for intensive shrimp farming stretched this resource, and overpumping has led to serious land subsidence, even exceeding 2m. Pollution problems and disease have also affected the industry and where major contributing factors to the eventual collapse of the shrimp farming industry from 80.000 t in 1987 to 20,000 t in 1988.

The recent development of competitive culture systems on main land China and through out the rest of Asia; has meant that the future of the Taiwanese aquaculture industry is not certain. However, recent government control over licensing water use and effluent discharge, combined with better management practices, should help to direct the industry as it evolves in the future. Meanwhile, the Taiwanese experience provides a good educational model to other developing nations on how aquaculture should be planned (Chen, 1990).

Some other areas of potential conflict include:

-   reservoirs and rivers; demands for drinking water, irrigation, recreation;

-   river supplies, problems during dry-weather flow, waste uptake and accumulation, residual flows available for other requirements;

-   water quality effects downstream or around the installation; escaping stocks, etc.

-   problems of diminished amenity, effects on tourism, eg angling sailing, visual conflict.

6 Environmental management issues

6.1 Introduction

The first point is that aquaculture should be subject to environmental management-to protect its surroundings, to ensure good practice, to reassure others and to protect its own needs. The second is that by taking steps to participate in such management, the industry should be seen as acting responsibly for the benefit of the community, and as showing the lead to other users of similar resources. However the industry is small by many standards, and compared with the overall size of resource-eg inland area, lagoon, coastal area or coastline length, its scale would be modest. A part from the conclusion that its impact might be insignificant, this also suggests that its environmental management, thought stringent and tough if necessary, should not be over-elaborate and burdensome. The approach used should take account of:

-   simplicity; it should be as easy to operate as possible, and be clear and understandable to all those involved, including the public;

-   rationality; it should be based on logical and scientific foundations, providing testability and, once operational, offering predictive power;

-   equity; it should operate fairly on all those involved with ‘using’ the resources, according to the degree if use; this should extend to apply to all users, as well as aquaculturists;

-   capacity; of the institution (s) charged with carrying it out; subject perhaps to a modest amount of training and/or equipment, it should be within the operational capability of the system, whether established within the public or the private sector, or both;

-   cost; the system system should not be too burdensome, and either overload or excessively inhibit the activities it is designed to cover, or place too great and imposition on the agencies responsible for its operation.

The main components to environmental management approach would therefore be:

-   at the installation stage; an environmental impact assessment procedure appropriate for reviewing new project proposals, or amendments or supplements to existing projects, prior to their establishment and possibly retrospectively;

-   at the operational stage; an environmental management procedure capable of monitoring the effects of aquaculture activities, and if necessary providing guidance for modifying installations and/or operations to minimise impacts;

An initial step might be to consider the potential effects of marine and freshwater aquaculture. These have been sufficient studied to allow prediction of the nature and scale of potential impacts in most situations (eg Hakanson et al, 1988) Effects on the quality of receiving waters and the associated sediments are the areas of most concern, particularly in relation to the input of nutrients. There is also a variety of other issues, such as chemical treatments and genetic pollution.

6.2 Environmental Impacts

6.2.1 Nutrient inputs

Aquaculture systems cannot avoid discharging nutrients, and in most cases they are readily absorbed within the normal processing capacity of the aquatic environment. Indeed in certain conditions the enhanced nutrient levels may have beneficial effects on secondary productivity and on local fish yields. The main approach to control is to attempt to reduce the quantity produced, or to reduce its specific impact, if for example there is evidence of particular local sensitivity. This can be done by improving feeding efficiency - which is in the interests of the farmer, or on land-based farms by installing mechanical and biological filtration. Cages can also be moved to less sensitive areas, or to locations where nutrients might disperse more readily.

6.2.2. Sediment deposition

Aquaculture sediments are in themselves usually very localised and are rarely problematic, though care has to be taken to avoid excessive accumulation in sensitive areas, or excessive nutrient and reduced gas release under the deoxygenated conditions which can arise within deep sediment layers. Control of the effects of sediments can be carried out by feeding control, and/or by trapping them on screens or in chambers, though physical removal may in some cases be costly. Coarse sediments in particular can be reasonably easily removed from pond and tank systems, and if in a freshwater medium can be quite useful soil fertilisers. However marine materials, particularly from cages, are difficult to collect and handle and due to their saline content are better disposed of within the marine environment.

6.2.3 Chemical treatments

There are other important operating features which may have impacts on the environment. The use of disease chemicals, which can include compounds ranging from antibiotics such as oxytetracycline to parasite treatments such as malachite green and organophosphate pesticides (reviewed in NCC 1989, 1990), is a widespread practice, particularly in intensive farming operations, and requires careful, compound-specific regulation and monitoring. This is particularly the case where materials or their breakdown products have an unknown and/or possibly longlasting fate or effect in the biomass or sediments into which they pass.

6.2.4.Escapes of stock

Cages may become damaged (eg storms), or ponds or thank may flood or overflow, resulting in the uncontrolled release of large numbers of stock. More commonly, small numbers may be periodically lost to the local environment during handing, draining, etc. If the species cultured is native to the region, the impact might be minimal, but if the release is large relative to the size of the local population, the possibility of ‘genetic pollution’ or dilution of the local gene pool may occur. If the species is an imported variety (eg tilapia), the possibility exists that it may become established within the local environment, and may possibly spread to other ares, with unforeseen consequences for the native fish community. It is firstly important to avoid unnecessary introduction of non-indigenous species, particularly if it appears that local stocks might be sensitive to competition. Once farmed, good practice should include regular checking of cage netting, screens and pipes, to avoid escapes.

6.2.5 Predator control/Hazards to wildlife

Predator control remains a problem, and although farmers may site their operations well away from known populations, the presence of a farm will encourage visits, and possibly the buildup of predator colonies near the site. Although a range of behavioural methods have been applied, there are no completely reliable yet harmless methods for predator control, and some accommodation usually has to be found between farmer and wildlife. It should be possible for this to be done without threatening predator population viability.

6.2.6. Visual and positional impacts

Most of these problems can be resolved by careful siting and marking of project units and/or by good quality landscaping, possibly also with some degree of public access, to highlight the positive and interesting aspects of the industry. In some cases, judicious use of colour and shape can greatly improve visual impact of fishfarming installations (see eg Cobham Resources 1988), and in some circumstances-eg with ponds, waterways and careful landscaping and planting, significant improvements may be achieved over pre-development conditions.

6.3 capacity management

Aquaculture is only one of a range of man's activities which can influence the quality of water, and although at times conspicuous in a particular location, is usually of only limited significance as a source of nutrients. In Denmark, Sweden & Finland, for example, marine aquaculture has been estimated to account for less than 1% of the total loading of nitrogen entering coastal water (Hakanson, 1988), with the remainder attributable to agriculture runoff and industrial and domestic effluents. The most useful and effective method of assessing the contribution of effluent from aquaculture (or indeed any other contributor) is therefore to consider the total mass of nutrients (estimated from mass-balance calculations e.g. Baird & Muir, 1990) as the loading on receiving waters, and to estimate impact according to the capacity of the system to absorb this loading, together with any other inputs which may be received.

This has led to the development of ‘carrying capacity models’, e.g. cage farms in lakes (Beveridge, 1984), Which can be used as management tools to control input of nutrients such as nitrogen and phosphorus at sustainable levels. The aim of such models is to allow estimation of the maximum quantities of nutrient input which water bodies (e.g. lakes, bays, rivers, aquifers) can sustain before a pre-defined change in water quality will occur. Perhaps the best known o these models is that described by vollenweider (1976), in which the sensitivity of lakes to phosphorus loading is predicted from information on the lake's mean depth and turnover time.

Although this particular model could not be directly applied in the marine environment. (Makinen, 1991), it illustrates the simple principle that the sensitivity of a habitat is related to its shape (area-volume characteristics) and the amount of water flowing through . Thus in marine coastal areas, sheltered bays will generally be more sensitive to nutrient loadings than open bays or capes.

6.4. The development of environmental information

Much of the information currently available for aquaculture projects has been collected on an ad hoc basis, mainly consisting of a small number of environmental impact studies e.g. reports on power station and harbour developments. These typically include information on the adjacent benthic and littoral community, with a small quantity of localised hydrodynamic and water chemistry data. These data are typically collected to obtain site-specific information, and do not constitute a basis for assessing the current state of the marine coastal environment.

The development of procedures for regulating and monitoring the marine aquaculture sector offers an ideal opportunity to develop a strategic approach to monitoring the marine coastal environment. The approach advocated here is that the Fisheries Department should take responsibility for this process, by developing a monitoring program (a suggested scheme is outlined below), but that the aquaculture industry should also be directly involved, for two reasons: firstly, it emphasises the fact that the aquaculture industry depends on a clean water supply for its existence, and thus the safeguarding of the marine environment is in its own interest, and secondly that as a new industry, it should be in the forefront of the development of better practices of environmental management.

6.5 Zoning for aquaculture?

The question of specific zoning for aquaculture purposes has been considered in a range of countries and individual locations. Four levels might be defined, which are, in increasing order of the degree of predefined planning control:

-   Not to specify any particular zones or locational constraints, such as minum acceptable distances, or specified ‘no-development’ Zones, but to assess each proposal on its particu lar characteristics, resource demands, and potential consequences. This provides the major advantage of flexibility, particularly if the technical locational constrains are not too well defined, eg because of the lack of knowledge of detailed site requirements and/or consequences to other users. The main disadvantages are the lack of ready guidelines for developers and the consequent uncertainty, and the potential lack of protection afforded to other users if the full consequences of development are not initially apparent. This approach is however quite widely used, particularly in the early developmental stages.

-   To define specific ‘non-aquaculture’ zones, but to allow development elsewhere on the basis of site and project justifications. This level removes much of the ‘lack of protection’ concern of the first approach, though to be properly effective, and reasonably equitable should not overemphasise the number and extent of protected zones, which in some cases might easily be claimed on rather spurious grounds.

-   To define minimum distance standards, either with or without protected zones. Although these minimum distances may be rather arbitrary, this does offer some readily calculable guidance for site location, and may for example be combined with a review clause allo wing individual case exceptions to be made, or for overall adjustment if it is found that specified distances are too lax or too strict. For illustration, typical specifications for the UK industry are shown in table 5. These guidelines are almost entirely arbitrary. though based loosely on concepts such as risk of disease transmission, and potential visual disturbance. It must be emphasised that these are industry and environment specific, and cannot be transplanted to other situations without careful analysis of actual locational constraints.

Table 5 Suggested separation distances for UK aquaculture industry

Note : subject of local agreements, eg between fishfarmers, or between fishfarmers and other, these distances may be reduced, also sitting around, eg headlands, or with tree cover may reduce visual distances.

-   To specify particular zones for aquaculture, with or without distance standards. This has at least the merit of appearing to be a positive support for the sector, though there may be the risk that if site requirements are not properly understood, the allocated zones may not be suitable, or may be severely though unintentionally limited in potential. On the positive side, and assuming the provision of adequate and suitable resources, this approach may imply some degree of protection for the sector competing users.

Under various planning provisions, a number of Mediterranean countries already make primary site or zone restrictions affecting aquaculture. Primarily aimed at allocating tourist development, residential, agricultural and industrial use on the coastal margins, this has now resulted in the definition of specific coastal development zones.

7 Environmental management in practice

7.1 Introduction

Environmental impact assessment (EIA) procedures generally have four basic aims:

-   to encourage developers to consider the potential environmental problems that could occur as a result of their proposed developments

-   to allow regulators to assess the potential impacts of specific developments in wider environmental context

-   to provide ‘pre-impact’ information on the state of the local environment

-   to allow regulators/decision-makers to make rapid assessments, on a cost-benefit basis, of the desirability of a particular development.

A variety of approaches have been advocated for the assessment of environmental impact, ranging from simple procedures such as checklists, to more sophisticated techniques such as matrix manipulation or networking (for a review, see Shopley & Fuggle, 1984). While techniques such as networking allow the complex higher-level interactions between different components, within proposed development projects to be identified, they suffer from a number of practical problems, among the most serious of which is their general incomprehensibility to the end-user. In many cases, this can result in their findings being downgraded in importance, or even ignored by those unfamiliar with the techniques employed.

7.2 A procedure for aquaculture

This procedure advocates the preparation of an environmental impact statement (EIS) using a standard checklist approach, with the added assumption that the person preparing the EIS has access to a database of information concerning various aspects of the environment of Cyprus, the details of which will be made explicit below. The key feature of this aproach is that if applicants have guidance as to the technical requirements of the EIS, and access to the relevant data, the preparation of the impact report should be straightforward. This would reduce the work required of external consultants, particularly in relation to collection, processing and analysis of water samples, and the collection, identification and enumeration of biological samples, since much of the background information about proposed sites would already be available.

This approach has a number of additional advantages:

-   it is ‘user-friendly’

-   it reduces the volume of the report (by excluding irrelevant information)

-   the report becomes easier for non-technical personnel to evaluate

-   it is cost-effective, for the reason listed above

Checklist and background details would be available to potential developers, and would assit them in preparing succinct and effective environmental impact statements, and that in turn the relatively standardised content would simplify the task of project assessors, and enable projects to be judged on a reasonably comparable and objective basis.

Unless specifically demanded by controlling authorities or the industry itself, this approach could avoid the need for any specific zoning or distance regulations. However existing planning zone framework could define the areas in which aquaculture proposals were unlikely to be accepted, although there may be difficulties in the formal definition of aquaculture within the activity categories used (see the accompanying legal report). Reference to this framework should at least make it possible to define for example a three-tier ‘acceptance ranking’, ie;

-   ‘improbables’-areas unlikely to be acceptable; too many conflicts of interest and/or difficulties with respect to existing zoning;

-   ‘possibles’-areas which might be acceptation; subject to resolving local issues, and within reasonably compatible zoning categories.

-   ‘suitables’-areas which are likely to be acceptable; should have little conflict of interest, and no diffuclties with respect to existing zonings.

7.3 The regulatory and monitoring framework

The second component of environmental management would be that of operating a suitable and effective regulatory and monitoring system. The framework for this should be rational and equitable, and should through selection and control aim towards the best use of water resources. Some of the important aspects would include.

-   conformance with procedures for EIA preparation; and subsequently strict adherence to EIA guidelines;

-   operation of a license system, with an approval process, and recovery or recognition of costs; license continuation would be subject to compliance with monitoring requirements (stats/surveys/inspections); there should be no attempts to penalise the industry, rather to promote and ensure good practice;

-   the development of a database for interrogation; the ultimate goal would be a carrying capacity model (N,P,C) for the coastal zone, in conjunction with localised models for specific site areas.

Both industry and the relevant regulatory authority would actively participate in the monitoring and management process. The concept is based on simplicity and the minimum of intervention necessary for protection. It is also assumed that the EIA process will eliminate unacceptable systems, and/or the use of unsuitable sites. Given the nature and overall levels of waste output, it is not considered appropriate to set specific concentration-based limits, though it is suggested that land-based farms should as a matter of course install primary waste water treatment systems. This is based on the principle that where viable means are available, they should be employed, and this might ultimately be extended to offshore areas. In the absence of objective criteria at present for specific localised impact, and given the need to ensure reasonable equity of application, we do not propose to set standards, but would recommend that land-based producers proceed with initial installation, with a view to steadily improved treatment over a specific timescale-perhaps 2 to3 years.

The role of the regulatory authority would include producing and maintaining a database of information on the current state of the marine and freshwater environments. This database should contain up-to-date information on nutrient status and other characteristic of potential receiving waters, the location of protected and/or protected species or communities, and the location of aquaculture and other significant users of water resources. The authority would define and control good practice through the issuance of production licences and renewal on an annual basis, and would encourage participation with the industry. However, it should not apply such controls penally and summarily, but should rather use them to move the industry progressively towards higher standards.

The industry should be required to carry out appropriate monitoring and control procedures according to the system/environment involved including:

1. Operating efficiency;record feed inputs (quantity and type used, nutrient content-N&P) and production statistics(stock sales, standing stock, mortalities) to calculate food Conversion ratio (FCR);operators should also record predation incidents and steps taken for predator control;

2. Assessment of impact on sea-bed around the cage site would be monitored on an annual basis, either by diver survey or remote video camera-this could be supplemented with simple benthic sampling if justified by the information to be gained;

3. Effluent treatment;all land-based marine farms should install an appropriate effluent treatment systems, which allows interception and collection of suspended solid effluent (wastes and uneaten feed). The system should be adequate to cope with expect quantities of effluent load appropriate to the production levels specified. The treatment system should also be subject to a minimum annual inspection (with perhaps a 24 hour warning), to establish that it is being effectively operated. Farm operators should keep up to date records on the quantity and disposal of effluent sludge, and should also carry out simple shoreline surveys.

7.4 Developing an environmental database

There is great interest among those involved in the conservation of the natural environment in the collation of basic environment data in the form of databases. For some, however, this is merely an excuse to collect large quantities of loosely collated information, the nature of which often reflects the bias of the collector, and the structure of which often limits the analytical, predictive and developmental power of the database. The aim should, therefore, be to produce a properly structured database of information on key environmental parameters obtained from a well-organised extensive field survey programme, coupled with a more intensive sampling programme at a small number of well-defined monitoring reference sites.

For the latter, the number of sites to be chosen for monitoring should be decided beforehand, based on the capacity to process samples and the optimum sampling effort per site. Obviously, such a database will take a number of years to become fully functional, and will require a high degree of coordination, in order that consistent and representative information is collected. However, if this is properly formulated at the outset, it can represent significant savings in scientific effort and provide substantial gains in informational quality. Such a database might also have an important role in key international activities such as the Mediterranean Action Plan, and given its wider interest and applicability, might well justify funding from a wider range of sources. In particular it might be valuable to use such an approach as the basis for developing a programme of international collaboration to facilitate research in key areas (especially taxonomy & ecology), which in turn would be of key importance in the development of a regional level coastal management strategy.

In general, compliance with the EIA guidelines, and any specific regulatory measures arising from the evaluation procedures should be carefully monitored and enforced. Enforcement would be achieved through annual licence renewal procedure. Impacts can only be assessed by reference to background information. Ultimately, the aim should be to develop a carrying capacity model for the coastline (or perhaps separate sub-models for ‘aquaculture zones’) if appropriate, there may also be a watershed or aquifer carrying capacity model for inland areas, involving ‘baseline’ or ‘status’ studies of managed watersheds/groundwater systems.

The development of suitable models allows the estimation of the impact of loadings on the nutrient status of environments, particularly in relation to the phenomenon of eutrophication. Initial EIA allowances would be made on the assumption of minimal eutrophication effect, and operators would be licensed for an appropriate discharge level, based on intended production and specified feeding effciency. Additional output could only come about through improved use existing feed input allowances, reduced nit nutrient input per production, or through additional EIA presentations to request further quantitative discharges.

Depending on the findings of the background studies, the regulator would be empowered to amend loading allowances and/or to require cage farm operators to move location, though the basic principale should be that if a loading allocation is made on the assumption of particular environmental limits, the right to operate to these limits would be maintained. If changes are required to these limits, they should be applied ‘across the board’ to all users.

The regulatory framework should emphasise the ‘best economic use of water resources’- this may in the long term rule out certain forms of aquaculture, or may move practice towards more environmentally-acceptable directions. For shore-based operations, effluent production can in any case be limited by the installation and appropriate management of waste treatment systems (e.g.filters, sludge collectors).

There are thus no explicit recommendations within this framework concerning zoning for aquaculture, as it is expected that these are almost ‘self-defining’ through the EIA process, and through the potential economic burden of modifying systems and/or practice to comply with requirements in more sensitive areas. In practice, therefore, avoidance of conflict with other of coastal areas (e.g.tourism, fisheries) can be achieved by de facto allocation within coastline areas.

7.5 Operational and resource requirements

The following resources and activities would be required for a typical environmental management programme:

-   personnel (chemist, oceanographer, biologist)

-   equipment (analytical, survey)

-   training & quality control

-   liaison with other government departments(e.g.reservoir water quality, groundwater quality etc.)

The adoption of a programme on the scale described above has significant resource implications, and increased levels of staffing, training, equipment and running costs are likely in most circumstances.

A database and monitoring system is only as good as the data it contains and uses - if data are suspect, then ‘advice’ becomes meaningless. Some problems already appear to exist between Government Departments in terms of chemical analysis methods for water, with freshwater analysis methods being erroneously applied to seawater samples, and the use of poor sensitivity methods (e.g portable analysis kits) being employed for low-level nutrient analysis. These problems could be easily solved by all laboratories adopting the procedures outlined in ‘Standard Methods for Water Analysis’ (the book published by the American Public Health Association). This could be further Strengthened by periodic interlaboratory calibration exercises, or at least some method of quality control.

One of the basic features of such a system is that the private sector should contribute to its costs. In the sense of individual companies, particularly fish farms, paying for monitoring of their own production sites, this is by no means unusual, and indeed in N Europe it is common for producers to pay some $5000–15000 per year per site;typically $50 to $200 per tonne of production. This is frequently over and above eg seabed lease charges. The departure in this case is that monitoring charges are aggregated and used to support the more strategic and coordinated studies described earlier.

In practice the licence cost might be increased to reflect a more realistic polluter-payment for monitoring procedures. Costs would vary with the amount of nutrients discharged, thereby relating price. directly with potential environmental ‘use’. Costs of inputs to the EIA should if possible also be recovered. Typical charges might be as follows:

-   Initial EIA application; use of background data;$500–1000, plus standard charges as appropriate for benthic and water quality analysis, current measurement sampling;

-   License fee; annual charge of $500–1000, plus $50–$80 per tonne of feed used;thus approximate costs would be:

• for a 50t farm   : $300 – $5000$ $60–100/tonne
• for a 100t farm : $5500 – $9000;$55–90/tonne
• for a 500t farm : $25500 – $41000;$51–82/tonne

The aquaculture licence systems might be expected to generate a useful share of the costs of developing the monitoring and management programme. Ideally, this mechanism could be used to cover other users of water quality, extended eg on the basis of allowed load of N, P, oxygen deficit or BOD equivalent, in which case far more of the real costs of environmental management could be recovered. Political process apart, in practical terms one of the biggest problems may be that of identifying a suitable administrative mechanism allowing licence funds to be allocated directly into support of the study and monitoring programme.

PLANIFICATION DE LA RECHERCHE EN AQUACULTURE

Par Philippe FERLIN, IFREMER

Depuis quelques années, la recherche en aquaculture, aprés avoir connu des périodes fastes, basées sur la certitude que tout investissement dans ce secteur allait rapporter des résultats mirobolants, se heurte à une certaine lassitude aussi bien du coté des pouvoirs publics que des producteurs, déçus par tant d'échecs ou de lenteurs. Cette situation vient souvent d'un manque de dialogue entre les principaux pôles de décisions concernés et les scientifiques eux-mêmes. ll est donc nécessaire d'analyser la nature des besoins de ces pôles et aussi leur attente.

La recherche aquacole est effet une recherche dont la gestion se situe à la croisée de 3 pôles de decisions:

-   l'administration chargé du dévelopment de l'aquaculture,

-   les producteurs eux-mêmes,

-   le Ministère, Secrétariat d'Etat ou Conseil national chargé du dévelopment de la recherche et de la technologie.

Chacun de ces pôles de décision a ses propres objectifs, ses propres moyens et ses propres systèmes ou structures de fonctionnement. Le but de cette note est de bien identifier ces différences, voire divergences, de faĉon à ce qu'au niveau national, la planification de la recherche puisse répondre aux besoins de ces divers acteurs.

1- IDENTIFICATION DES BESOINS ET DES OBJECTIFS

a) Producteurs

Le secteur productif est l'utilisateur final de la recherche, mais ses besoins identifiés par lui-même sont limités à des recherches à court terme, répondant à des problèms brutalement apparus ou des évolution dont le dévelopment peut mettre à court terme ses exploitations endanger. Parmi ces problèmes, on peut citer:

-   l'apparition d'une épizootie brutale,

-   la lutte contre la concurrence grandissante de produits en provenance de l'etranger à meilleur prix,

-   la nécessité d'ouvir de nouveau marchés, etc.

Les objestifs de la recherche aquacole voulus par les producteurs sont généralement des objectifs à court terme (de l'ordre quelques mois à un ou deux ans). Sauf exception, un producteur ou même un groupe de producteurs peut difficilement investir dans des recherches à plus long terme, même si cet investissement s'avére rentable. Il faut cependant dés maintenant remarquer que certains problèmes immédiats rencontrés par les producteurs ne relévent pas d'une recherche àcourt terme, mais àlong terme:ainsi, le traitement d'une épizootie brutalement apparue, peut demander plusieurs années de recherche. Ceci peut amener une première contradiction entre les besoins des utilisateurs des résultats de la recherche et les possibilités des acteurs de cette dernière.

b) L'administration chargée de la gestion du secteur

L'administration en charge de l'aquaculture, prend en compte si elle en est proche, les besoins des producteurs, mais elle y en ajoute d'autres liés à son rôle économique et social de«development» ou d'aménagement», et depuis peu d'années de garant de «l'équilibre écologique». Parmi les problèmes pris en compte, figurent ainsi:

-   l'étude des sites aquacoles, en vue d'une planification territoriale,

-   le développment de technologies plus douces,

-   l'introduction d'espéces étrangères,

-   la gestion de la pêche d'alevins, etc.

Ses objectifs sont donc généralement des objectifs à moyen terme, relativement finalisés, recouvrant ou non ceux des peoducteurs. Ils portent généralement sur des recherches technologiques, zootechniques, economiques ou socio-économiques.

c) Le Département chargé de la recherche (s'il existe)

L'aquaculture dans cette structure n'est généralement pas traitée comme un secteur à part, mais n'est considéré que comme un secteur d'application de recherche «générique», développant de nouvelles connaissances de base ou de nouvelles methodologies, utilisables dans le domaine plus vaste de la production biologique. Les problèmes abordès concernent par exemple:

-   le dévelopment de nouvelles approches en matière de génétique,

-   l'utilisation de la biologie molléculaire dans le domaine de la pathologie,

-   l'approche systèmique des ressources renouvelables, etc

Les objectifs recherchés sont alors à long terme (5à 15ans), et ne sont atteingnables que par la combinaison de moyens importants et souvent pluridisciplinaires.

Nous voyons donc que lorsque l'on parle de la planification de la recherche aquacole, ce terme recouvre tant d'activités qu'il est important de bien cerner les objectifs à atteindre en fonction des besoins des divers acteurs.

2- LES MOYENS

Chacun de ces pôles de décision dispose également de moyens différents, tant au niveau des structures de recherche que des financements mobilisables.

a) Producteurs

Les producteurs, comme nous l'avons vu sont intéresés par des résultats à court terme, et ne peuvent investir que dans des programmes limités dans le temps et en volume financier. Il est encore rare que le secteur productif se soit doté de ses propres structures de recherche, comme cela est souvent le cas en agriculture. Les producteurs vont donc soit essayer de mener des recherches dans leurs propres installations de production (mais ceci reste trés limité dans les résultats escomptables), soit d'influer sur le choix des programmes des instituts de recherche d'etat, par du lobbying ou des financements. Cette situation peut à terme, si la pression des producteurs devient trop grande, peut entraîner un détournement de la recherche public, qui ne va plus se consacrer qu'àla résolution de problèmes immédiats, voire faire du dévelopment quand elle ne s'occupera pas de tâches de routine devant être exécutés par les producteurs eux.mêmes.

b) Administration chargée du secteur

L'administration peut mettre en oeuvre des moyens de recherche appliquée beaucoup plus important, sous condition que les résultats obtenus permettent à moyen terme le développement du secteur aquacole. Elle peut ainsi créer des stations et laboratoires de recherche, et financer des programmes de plusieurs années en proportion des budgets généraux qu'elle consacre au secteur. Le risque est ici de sous-estimer ces moyens et également les délais nécessaires pour obtenir des résultats fiables, ou de les détourner vers des besoins à trés court terme de l'administration défaillante:le scientifique, sous prétexte qu'il est financé par l'adminstration, devient le «conseiller technique» permanent de cette administration incapable de créer sa propre capacité technique ou économique. Tous les Instituts de Recherche sur les Pêches ou l'Aquaculture en sont malheureusement passés par la!

c) Département de la Recherche

Tous les pays n'out pas encore dc structures administratives centralisées de la recherche scientifique, mais le nombre de pays qui s'en munissent augmente régulièrement. L'avantage de ces structures est de pouvoir gérer des moyens beaucoup plus lourds que ceux de la recherche sectorielle (équipes scientifiques, grands équipements) permettant de programmes plus ambitieux et a plus long terme. Ceci intéresse l'aquaculture, mais il est rare que celle dernière puisse influer directement sur les programmes et les moyens ainsi mobilises. En revanche, elle ne peut pas les ignorer, et doit au contraire valoriser par des recherches aval les acquis a dus à ces moyens.

En conclustion, l'étude des moyens mobilisables, nous montre également que comme pour les besoins et les objectifs, il ne faut pas se tromper:inutile de demander à des producteurs de financer un programme (en les équipements nécessaires) de biologic molléculaire pouvant à terme leur permettre de disposer de nouvelles souches, ni au Minsitère de la Recherche de s'occuper de l'étude d'une pollution qui aurait détruit localement la production d'une ferme aquacole.

3- STRATEGIE ENVISAGEABLE

La stratégie propos´e pour une planification de la recherche en aquaculture repose sur 3 principes: coordination nationale,«feed-back» permanent et information sur les programmes existant dans des secteurs proches ou à l'étranger.

a) Coordination nationale

L'analyse précédente montre que toute planification de la recherche en aquaculture doit tout d'abord inclure les 3 pôles de décisions, au niveau de l'identification des besoins mais aussi des moyens et des programmes, et de leur mise en oeuvre. Coordination et réparation doivent être les bases d'une bonne planification.

Cette coordination / répartition qui peut s'effectuer au niveau d'un comité national, est indispensable si l'on veut éviter d'une part que des recherches finalisées n'aboutissent pas par manque de connaissances de base, el d'autre part que des recherches menées en amont ne soient d'aucune utilité ou ne soient pas valorisées.

b) Feed-back permanent

La recherche aquacole, comme toute recherche dans le domaine des ressources biologiques, n'est pas un processus linéaire, de la connaisance de base jusqu'à l'application :à tous les échelons, il est nécessaire de renvoyer à l'échelon précédent les information et les problèms rencontrés par la mise en oeuvre des résultats acquis. Les véritables problèms concernant le développement de l'aquaculture ne se sont pas rencontrés dans les laboratoires, mais au moments de leur application au niveau de la production; d'autre part, il est clair que la recherche finalisée doit en permanence renvoyer certaines questions à la recherche de base, quand le problème se pose.

Ce type de liaison peut s'établir sons la forme informelle de séminaires ou d'ateliers de travail, liant deux échelons de la chaîne recherche-déveolopement.

c) Information extérieure

La recherche aquacole n'est pas un monde à part:de nombreux problèmes sont proches de ceux étudiés par la recherche agronomique, ou pour ce qui concerne les liaisons avec le milieu, par les recherches sur l'environnement. It est donc indispensable de profiter des résultats ou des acquis méthodologiques de ces secteurs pour gagner du temps et éviter de dupliquer certains efforts.

It est aussi malheureusement encore trop courant de voir que dans l'élaboration de programmes nationaux de recherche aquacole, l'analyse des acquis sur le plan international n'est pas faite ou mal faite:que de programmes de recherche en nutrition, en reproduction, etc. sont effectués sans tenir compte des programmes déjà exécutés ou bien avancés, avec souvent des moyens beaucoup plus importants. Certains résultats sont même souvent transférés au secteur professional (producteurs ou sociétés de services) alors que des laboratoires continuent à perdre du temps, de l'énergie et de l'argent sur le sujet, au lieu de les utiliser sur d'autres priorités. Une telle information est donc indispensable, et peut venir soit de la bonne liaison des scientifiques nationaux avec des équipes de recherche extérieures, soit d'un système règional d'information (SIPAM on Mediterranean Action Plan).

4- CONCLUSION

Au vu de ces considérations, on peut tout d'abord dire qu'il n'existe pas de méthode spéciale de planification de la recherche aquacole. Tout au plus, peut-on dire que celle-ci se rapproche de celle utilisée pour les autres ressources biologiques, Cette planification doit s'adapter au cadre national, variable d'un Etat àl'autre, en tenant compte des structures et des moyens existants; elle doit aussi reposer sur uneévaluation des priorités économiques, sociales, écologiques et évidemment politiques de chaque Etat.

En revanche, l'aquaculture étant encore dans un état de maturité précaire, il est nécessaire de rappeler que la recherche dans ce secteur n'est pas gérable, si les 3 pôles de décision présentés ci-dessus ne sont pas impliqués, et si d'autres secteurs ne sont pas associés (recherche agronomique, environnement). Ces quelques recommandations devraient ainsi permettre d'éviter les embûches du passe, et redonner confiance aussi bien au secteur professionnel qu'aux décideurs publics dans la recherche aquacole.

LE PLAN DIRECTEUR D'AQUACULTURE EN TUNISIE

Par Hédi GAZBAR
Tunisie

L'aquaculture en TUNISIE vient de franchir d'importantes étapes en matière de recherche de l'expérimentation lui permettant de se lancer dans la réalisation de projects à caractère commercial et industriel.

Les quelques projects initiés par des privés et des banpues de développement laissent espérer un avenir intéressant d'autant que :

-   les potentialités de la pêche maritime ont atteint et même dépassé dans certaines régions le seuil limite de leur exploitation (120% en1991 dans la zone du Golfe de Gabès);

-   des possibilités de développement de l'aquaculture existent vu des conditions géographiques el climatiques favourable et un potentiel hydrique important ;

-   la Tunisie dispose de spécialistes et de techniciens en aquaculture;

-   la demande sur les espèces produites par l'élevage est importante tant sur le marché national qu'international;

-   pour toutes ces raisons, l'aquaculture occupe dans le VIII-ème Plan une place significative dans l'économie tunisienne avec une production de 3000 tonnes en 1996 et de 10,000 tonnes àl'horizon de l'an 2000.

Vu l'intérêt que porte la Tunisie pour l'auaculture el son développement, il est donc nécessaire d'exploiter rationnellement les sites aquacoles el de les bien gérer.

Il est de ce fait recommandé d'identifier les sites favorables à l'aquaculture et de les aménager conformément à la stratégie du développement du secteur.

Face à cette situation, il apparait nécessaire que l'administration compétente dispose d'éléments objectifs de décision et de planification qui complèteront ses capacités d'analyse.

Les partenaires institutionnels (Etat, Banques…) doivent disposer d'un inventaire des sites potentiels de l'aquaculture et une vision des réelles perspectives techniques du ´conomiques du secteur afin de mettre en place les moyens nécessaires à la poursuite d'un développement maîtrisé du secteur.

Le développement de l'aquaculture, secteur en grande partie exportateur doit être planifié dans un objectif de rentabilité micro économique et de compétitivité de la production tunisienne sur les marchés extérieurs, et notamment du marché unique européen.

Ces constats nous ont conduit de prendre la décision pour l'élaboration du Plan Directeur de l'Aquaculture.

Compte tenu de la pression foncière, de la concurrence d'activités et des questions d'environnement, le P.D.A établiera un inventaire exhaustif des sites potentiels. Ses conclusions seront prises en considération an niveau de la planification de l'aménagement littoral, afin de préserver des sites potentiels pour l, activité et de permettre une meilleure intégration de l'aquaculture dans l'environnement.

Le PDA doit être donc en mesure de satisfaire tous les partenaires du secteur qui seront concertés à cette occasion: Promoteurs, administrations, régions, institution de recheche, banquiers, bailleurs de fond, etc…

Pour tous ces agents du développement économique, le PDA doit être une source de données et de clarification des procédures, de diminution des risques; le PDA doit proposer des objectifs cohérents, coordonnés, et complémentaires à partir de l'analyse du passé et de l'examen détaillé des différentes filières adaptées à l'environnement tunisien.

Pour l'administration en particulier, le PDA permettra l'équité des agréments et concessions, la modernisation de la réglementation, l'adaptation éventuelle de la politique d'incitation, l'arbitrage entre les activités, la protection foncière et le respect de l'environnement.

La réalisation du PDA qui sera exécutè à partir des prochains mois, se base essentiellement sur l'association étroite de l'expertise internationale pluridisciplinaire aux compétences nationales.

Ce projet sera cofinanceé par le Gouvernement et le PNUD. La durée de son exécution est de 2 ans.

Le Plan Directeur englobe trois parties:

1. Bilan Diagnostic,

2. Stratégie sectorielle de développement,

3. Le PDA en tant que document exécutoire.