3.1 Sustainable development
3.2 Developmental issues
3.3 Role of rural aquaculture
Over the past decade there has been increasing recognition that development should be sustainable. Various definitions of sustainable development have been proposed; one that is widely accepted is that of the Brundtland Report (WCED, 1987):
Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.It contains two key concepts:
It also suggests that overriding priority should be given to the satisfaction of the needs of the worlds poor. The major question for the purpose of this series is the extent to which aquaculture can contribute towards sustainable rural development.
It should be stressed that sustainable agricultural development does not call merely for the conservation of natural resources. The word development implies an improvement in the livelihood of the mass of the population in rural areas. There seem to be increasingly pessimistic views on the potential to do so through the irrigated lowlands which are the traditional centres of agricultural development. While intensification in such areas has brought about impressive increases in food production, especially in Asia, there are increasing pressures upon land and water resources. Indications of environmental degradation from over-use of fertilisers and pesticides are increasing. As these factors begin to place limits on sustainable productivity in favourable areas, attention must be turned both to alternative agricultural systems and to the use of less favourable areas within their more fragile and diverse systems. However, these are also under threat from population growth and appropriation of the resource base from the lowlands, causing ripple effects into the exploitation of erstwhile common property resources, the last resource frontier. Promotion of aquaculture to contribute towards rural development in inland areas must be considered in relation to this broader agricultural picture.
3.2.1 Major problem areas
3.2.2 Rural versus peri-urban aquaculture
Four major factors in development (growing population, natural resource exploitation, pollution, and unequal development and distribution of wealth or inequity).interact in a complex and often misunderstood way (Harrison, 1993).
The fundamental development issue is the recent rapid increase in global human population which is predicted to double from approximately 5.5 billion people today to 12.2 billion people by 2150 AD. Of major concern is the expectation that at least 90% of the global increase will occur in developing countries, most of these already densely populated.
Human societies almost always exploit natural resources by seeking to maximise short-term gain at the expense of the environment. The limitations of local and global ecosystems have repeatedly been exceeded beyond their carrying or assimilative capacity. Harrison (1993) states that three factors work together on the environment.
I = P x C x T
I = environmental impact;
P = population or number of people;
C = consumption by individual people; and
T = technology
A major share of the worlds resources are under the political and economic control of developed countries and elite groups in developing countries, leading to inequity. Rich people live unsustainably as they depend on a greater than average per caput share of the worlds resource base. Poor people also exploit natural resources in an unsustainable way for short-term gain to survive. Of major concern is the close to a billion of the global population undernourished or hungry. Attention to food security is required by ensuring that all people have access to sufficient food to permit active and healthy lives, either by producing it themselves or having the purchasing power to do so.
Urban settlements are almost as old as agriculture itself but rapid urbanisation is a recent phenomenon. The world was predominantly rural at the start of the industrial revolution 250 years ago, with about 2.5% of the worlds population living in cities. By the year 2,000 more than 50% of the global population will be urban. This has major implications for the growth of aquaculture. The promotion of rural aquaculture will need to be considered in relation to periurban aquaculture. Although the latter needs to be carefully defined, it may have comparative advantages in providing poor urban consumers with aquatic produce because of shorter input supply and marketing channels, and because of close proximity to domestic and agro-industrial sewage, by-products and waste which could be used as nutritional inputs.
The emergence of agriculture in the Agricultural Revolution some 10,000 years ago was a major step in the development of modern human society but it also started the world on the pathway towards the crisis facing us today. However, the Industrial or Scientific Revolution which began about 250 years ago is the major cause of unsustainable development. The move from a pre-industrial to an industrial society is often called development but there are fundamental flaws which must be addressed.
Natural resources are used as capital to generate assets as a source of profit, ignoring the fact that they are finite and once used are not available for future generations. The same applies to living natural resources such as wild fish stocks if they are not managed sustainably. Development has also given scant attention to social and environmental costs. These are major criticisms of the green revolution technology which should be borne in mind when talking about a blue revolution that aims to significantly increase aquatic production to contribute towards food security.
A new revolution or philosophy is required to promote sustainable development that will more equitably allocate resources among the world population. The western philosophy in which humanity is considered as above and not part of nature, with a mandate to exploit it, should be replaced by the oriental philosophy of man being part of nature.
3.3.1 Nutritional aspects of fish
3.3.2 Fish in food security
3.3.3 Aquaculture or capture fisheries?
3.3.4 Fish for food or income?
3.3.5 Poverty alleviation and rural aquaculture
Aquaculture needs to be evaluated critically in relation to its actual and potential contribution to rural development. The main objectives are household food security and income generation from sale of surplus production. Where aquaculture becomes part of a wider farming system it leads to agricultural diversification. This may offset risk and lead to a more environmentally sustainable farming system.
Fish are a highly nutritious food. They provide animal protein with all 10 essential amino acids in relatively high concentrations, and are rich in certain vitamins and minerals. They are low in cholesterol and saturated fats and are high in poly-unsaturated fats and essential fatty acids.
There is controversy concerning the role of fish in undernutrition, particularly protein-energy malnutrition. Initially it was believed that most undernutrition was associated with inadequate protein supplies. Thus high-protein food such as fish was recommended to alleviate undernutrition. Later it was believed that malnutrition was due to insufficient food rather than a diet with too low protein; if the diet supplied sufficient energy or calories then protein intake would be adequate.
It is now believed that the traditional high carbohydrate staple diet of most developing countries is adequate for adults. However, pregnant and nursing women, infants and pre-school children who cannot obtain sufficient nutrients from mainly cereal or tuber-based diets would benefit from inclusion of fish in their diets.
A recently discovered nutritional value of fish in their relatively high content of the poly-unsaturated fatty acid, omega-3 (n-3 PUFA). PUFAs are essential components of neural membranes and retinal tissues; they aid brain development of the human foetus. Pregnant and nursing women should therefore be encouraged to eat fish and shellfish to provide their unborn children and infants with essential nutrients. Marine fish have traditionally been associated with high amounts of PUFAs which are derived primarily from phytoplankton through the food chain. As freshwater algae are apparently as good a source of PUFAs as marine algae, freshwater fish cultured in fertilised systems should likewise be a good source. Fish also provide fats which are more energy-dense than either carbohydrates or proteins, an important consideration for infants.
Fish are less important than livestock as a source of animal protein, supplying only an average of 20% of the total for developing countries globally. However, in many developing countries, particularly in South and Southeast Asia, fish provide a higher percentage (30-50% higher) of animal protein and are important in food security. Those countries in which rice and fish are important traditional staple foods are referred to as rice-fish societies. Most countries have proverbs similar to the one translated from Thai: In the waters are fish and in the field is rice.
Analyses of fish consumption from Asian developing countries from 1961 to 1990 indicate a doubling of supply from 5 to 10 kg/caput/year i.e., it rose much faster than human population (Laureti, 1992). Fish protein in relation to total animal protein in the diet varied little from 25% to 23% in 1961 and 1990, respectively. The diet tends to diversify with development i.e., more meat and wheat, and less fish and rice but absolute fish consumption increases also. This suggests that aquaculture can be promoted to both alleviate undernutrition and contribute to rising living standards.
The amount of fish required to satisfy human nutritional needs has been estimated for hypothetical societies in which fish is important (with 50% of their animal protein provided by fish) and for fish-eating societies (which derive 75% of their animal protein from fish) (Mekong Committee, 1992).
Standard assumptions were based on minimal and optimal nutritional requirements (Figure 1). For societies in which fish is important and fish-eating societies, estimates are 22kg and 32 kg fish/caput/year respectively for minimal nutrition in which 1/3 of total protein is animal protein. Using optimal nutrition with animal protein providing 1/2 of total protein, estimates are 32kg and 49 kg fish/caput/year, respectively. The minimal household consumption (assuming five household members) to satisfy human nutritional needs where fish are important is thus about 100 kg fish.
Fig. 1. Estimates of fish consumption to provide minimal and optimum nutritional requirements for humans of animal protein in the diet in fish-eating societies (where 75% of animal protein is derived from fish) and in societies in which fish is important (50% of animal protein derived from fish).1
The lowest per caput estimate is double the current developing country average fish consumption rate of 10 kg fish/caput/year (Laureti, 1992) but fish consumption rates of 20-50 kg/caput/year are common in traditional fish-eating societies of Asia and the Pacific, thus supporting the validity of the nutritional estimates. Although there are undoubtedly culturally-determined upper limits to fish consumption in different societies, a huge unfilled need in relation to fish consumption is indicated. This conclusion is supported further by current average developed country fish consumption of 26 kg/caput/year.
The need for aquaculture to provide increased supplies of fish should be considered in relation to capture fisheries. These currently dominate production but are static or in decline globally and in most countries. As wild fish stocks are threatened by human population growth through overfishing and environmental degradation, the stimulus and need for aquaculture are greatest in developing countries where at least 90% of the global increase in population is predicted to take place before the world population stabilises at a level at least double that of today.
There will be a global need for about 60 million tonnes more table fish by the year 2025 (Csavas, 1994), assuming no significant increases in capture of wild fish, a median UN projection of population growth, and todays average global fish consumption of 13.5 kg/caput/year. This means that by 2025 aquaculture should produce three times more than today. However, it does not consider that people may consume considerably more fish to alleviate undernutrition. If a higher annual per caput fish consumption of 20-30 kg were targeted to take into consideration those societies in which fish is an important diet component, then aquaculture would need to increase globally considerably more, possibly five to six times more than the current level.
Most small-scale farmer aspirations focus first on subsistence but the interest shifts to income generation once confidence in the technology is gained. Traditional aquaculture systems probably functioned mainly to supply household needs but with the rapid expansion of the market economy in even remote areas, farmers are likely to be motivated as much by income-generating opportunities as for improved domestic food supply. Recent entrants to aquaculture in Svay Rieng province in Cambodia sold fish raised in their ponds and purchased cheaper wild fish from local markets.
Nevertheless, it is instructive to consider how much fish is required to satisfy household fish consumption needs for a non-vegetarian fish-eating household. A range of about 100-250 kg of fish would be required to satisfy the household consumption needs of a fairly typical household of five persons based on the assumptions in section 3.3.3 (Figure 1), a not inconsiderable amount from relatively small and typically resource-poor small-scale farms. Considerably increased levels of household production are required before aquaculture can contribute significantly to household income.
Aquaculture is as an important contributor to the alleviation of rural poverty, especially in Asia where wild fish is a traditional dietary staple in many countries. For many rural development specialists satisfaction of basic needs is the starting point for rural development while basic food security is a prime need. Moreover, in Asia, fish is seen as relatively high-value produce which offers an opportunity for agricultural diversification and improved earnings for small-scale farmers, where self-sufficiency in cereals has already been achieved but where small landholdings mean that rice can never offer a prosperous future. However, the generally poor results of the promotion of aquaculture in Africa and Latin America to alleviate poverty, and the better rate of success with more intensive systems of production by richer farmers, have cast doubts on the ability of aquaculture to fulfil such expectations.
Aquaculture is rarely appropriate even as a supplementary occupation for the rural poorest, particularly the landless. Where fish is a traditional part of the diet and alternative income sources are unavailable, resource-poor farmers have shown interest and ability to culture fish using low-unit cost inputs e.g. Cambodia, Lao PDR and Vietnam. It is a false dichotomy to believe that aquaculture is appropriate only for the rich, but not the poor rural farming households (Martinez-Espinosa, 1995). The evidence indicates that aquaculture has relevance for both groups of farmers but that the appropriate technology, methods to assess its role, and methods to promote it depend on the target group.
|1Assumptions: Total protein requirement
= 1 g protein/kg body weight/day; Average weight 50 kg; Minimal nutritional
need is 1/3 of total protein intake supplied by animal protein ; optimal
nutritional need - ½ total protein is animal protein.