Based on the socio-economic and environmental assessments carried out within the framework of Project VIE/93/001, it can be concluded that the majority of current aquaculture practices in northern Viet Nam is not likely to cause significant adverse impacts on the aquatic environment. In fact, most fish culture practices are based on utilization and re-use of on-farm feed/nutrient resources, often requiring very little renewal of water, with species being grown which feed low on the aquatic food chain and which are net protein producers. In addition, many farming practices found in northern Viet Nam show a relatively high level of aquaculture/agriculture integration. In fact, integrated aquaculture/agriculture farming systems are frequently being promoted in other regions because they are known to guarantee a very high level of environmental compatibility.
The Project, through its extension activities, is assisting many fish farmers in improving their integrated farming methods, and is therefore contributing to the adoption and expansion of environmentally sustainable aquaculture practices.
Based on the findings and recommendations of the Study Teams, and the findings of the two missions by the reporting officer, a set of consolidated recommendations is given below.
Chung and co-workers (Socio-economic Study) asked farmers about their most important needs in terms of technical advice and technology. Most farmers across all regions prioritized their most important needs as follows:
Given that many farmers still lack experience and lack of technical know-how, it is suggested that current (and future) extension efforts continue their focus of activities on provision of technical advice on above needs. More specifically, continued technical advice would be appropriate on following aspects:
stocking methods (including seed quality, stocking size of fish, stocking ratios, stocking density)
feeding techniques, i.e. on adequate preparation and use of on-farm inputs including in particular manure and nightsoil (eg. Thanh and co-workers recommend that livestock manure be treated before being applied to ponds; see also below)
fish health management (e.g. reducing stress, avoiding overstocking, safe and effective use of chemicals)
water quality management (e.g. use of inorganic fertilizers, avoiding over-feeding, pond preparation)
site selection (e.g. avoidance of natural hazards, risks of disease transmission and threats of external pollution)
basic record keeping (monitoring of inputs, outputs, and management measures; accounting for benefits and costs)
There is a continued need for additional hatcheries in lowland, midland and highland areas, as well as for a more decentralized seed supply system that reaches the small scale farmers (Chung and co-workers).
Both Study Teams identified the need for continued provision of advice to farmers and additional support to ongoing extension services.
Thanh and co-workers give following recommendations:
further technical training programmes are needed for extensionists working at both district and provincial level, and
it is essential to promote aquaculture extension activities at the district level.
Chung and co-workers stress that existing extension systems should be further strengthened, and that extension programmes should give further emphasis to increased participation of farmers in technology design and transfer.
Chung and co-workers also note that women play an important role in VAC farming. While men are involved in making decisions of fish species to be raised, timing of stocking, buying fingerlings, netting and harvesting, women are often involved in daily feeding and pond management, including gathering of grass, garden leaves, collecting of manure for the pond, and feeding rice bran to fish. Extension activities should consider these important gender aspects, and provide advice to women and men by targeting their specific roles in aquaculture practice.
Thanh and co-workers suggest that there is a need to provide a short training course to fish farmers on aquacultural techniques and their effects (i) on the quality of water and soil within the pond, and (ii) on the environment. This would enhance the farmers' awareness of important aspects and requirements to safeguard environmental health and safety within and outside their farm household.
The activities of the Project are proving to be very successful, and continued support to further increase the capacity of the existing aquaculture extension networks and their activities is recommended. It appears that there will be a continued need to train extensionists in specific technical fields, particularly in those fields being prioritized by the farmers (see 4.1).
RIA No. 1, as the Transfer of Technology Centre (TOTC) of the existing aquaculture extension network, will certainly have to respond to an increasing demand for technical backstopping by Sub-Centres and extensionists in northern Viet Nam. R!A No. 1 is making every effort possible to continue upgrading its technical competence in a range of technical fields (MoF/RIA No.1, 1995). However, it should be recognized that additional financial and technical assistance to RIA No. 1 will be essential in order to ensure that extensionists and farmers will be benefitting from technical advice which is up-to-date and which meets their immediate needs.
Chung and co-workers highlight the fact rice-fish intercropping helps to significantly reduce the use of pesticides. Collaboration with experts on Integrated Pest Management should be continued with a view to strengthening extension activities on rice-fish culture.
Based on their assessment of the expansion of ponds into the course of River Bui, Thanh and co-workers recommend that the department of agriculture and rural development of Bacninh province initiates, in collaboration with other relevant institutions, an overall planning programme for sustainable aquaculture development in these areas.
Given that a strong interest for new pond developments also exists in other areas, it may be convenient to consider approaches for assessment, planning and allocation of resource uses which cover wider agro-ecological zones such as the Red River Delta.
It should be noted that Thu and Demaine (1996) have applied GIS analysis to define areas in the Red River Delta with potential for (i) rice-fish rotation, (ii) intensification of small pond culture, and (iii) pond culture with access to additional, urban-derived inputs.
It is suggested that the findings on potentially harmful metal concentrations in fish meat from Duongsat Lake be brought to the attention of the Ministry of Health.
Based on their study of sewage-fed aquaculture systems in Thanhtri district, Thanh and co-workers recommend that further research and improvement of the systems be focused on following aspects:
Evaluation of the importance and effectiveness of a wastewater-fed fish pond system in terms of its wastewater treatment capacities as compared to conventional sewage treatment practices,
Improvement of the technology of wastewater reuse in aquaculture systems in terms of (a) fish species (especially tilapia) and its composition, (b) design and management of wastewater-fed fishpond systems and (c) management requirements in fish ponds utilized for different production systems,
Improvement of the wastewater supply system for aquaculture production,
Assessment of the potential risks to public health of wastewater reuse in aquaculture (including both aquaculture producers and consumers of aquaculture products).
Edwards (1996a) has recently proposed a project to determine the social, environmental, technical and economic aspects of low-cost sewage treatment integrated with food production. It should be noted that Dr A. Dalsgaard will be visiting Viet Nam in August of this year, on the occasion of a DANIDA funded project formulation mission, with a view to identifying key activities for a major project on the assessment and verification of human health risks associated with sewage-fed aquaculture systems as well as on the improvement of these systems for increased quality and production of fish grown in these systems. Following additional technical documentation may be useful for those concerned with human health aspects of wastewater-fed aquaculture in Viet Nam: Edwards (1996b), Dalsgaard (1995), Mara et al. (1993), Edwards and Pullin (1990). It should be noted that human health aspects of wastewater-fed aquaculture will be addressed during the forthcoming WHO/FAO/NACA Workshop on Food Safety Issues associated with Aquaculture Products. The Workshop will also discuss the Proposed Draft Code of Hygienic Practice for the Products of Aquaculture - Codex Alimentarius Commission (FAO/WHO, 1996).
Vietnamese experts are well aware of important environmental issues in aquaculture development. This was clearly demonstrated during the 1994 Workshop on Aquaculture and the Environment (MoF/NACA, 1995). The report and proceedings of this workshop, which include numerous technical presentations as well as conclusions and recommendations, have been published in both Vietnamese and English. It is suggested that the findings of this workshop be made available to experts and officials in research institutions and provincial and district authorities concerned with aquaculture development, resource planning and managment, and environmental protection.
It was noted that staff of RIA No.1 was not aware of the existence of the FAO Code of Conduct for Responsible Fisheries (FAO, 1995) and related Technical Guidelines (see References). It is suggested that this documentation be distributed to interested institutions.
It was noted that there is a need to provide additional training on environmental assessment methodology. Emphasis may be given in particular to training on planning and conduct of sampling and monitoring techniques, presentation of data, analysis and interpretation of results. Such training should provide for a broader understanding of purposes and requirements of environmental assessments in the wider context of resource assessment, planning and management for aquaculture development. Consideration of environmental and resource use issues, both at local level and at the level of agro-ecological zones, should be included in curricula of such training programmes.
There continues to be a need to facilitate and strengthen communication and collaboration among experts and officials in different research and government instiutions dealing with aquaculture, inland fisheries, water resource management, agricultural and rural development, public health and environmental protection.
In view of increasing industrialization and urbanization, problems of environmental degradation of aquatic ecosystems and resources may soon become significant issues for aquaculture and inland fisheries experts. Collaboration with environmental experts and institutions should be continued and strengthened to ensure that appropriate advice on threats of aquatic pollution be provided to fish farmers and fishermen.
It can be expected that certain types of aquaculture practice (e.g. cage culture) will be moving towards utilization of more intensive culture methods. Likewise, aquaculture of carnivorous species is likely to attract growing interest. Fish farmers employing such methods or species will need to be advised on the limits of intensification within their culture units. They will also need advice on measures to prevent that effluents from their farms exceed the environmental carrying capacity of receiving waters.
There is growing interest for shrimp culture development in northern Viet Nam. However, in other provinces there is significant evidence for cases of shrimp culture expansion which has led to low productivities and environmental damage resulting from uncoordinated development and lack of experience and technical skills.
It is felt that technical advice and research is and will be needed on sustainable coastal aquaculture practices in northern Viet Nam. Given the suboptimal conditions for shrimp culture development in northern Viet Nam, it is suggested that consideration is also given to the promotion of aquaculture of other species. RIA No.1 has conducted preliminary studies on the use of brackishwater areas for production of three consecutive crops of various species (e.g.: shrimp/tilapia/crab-mullet and other local species) which are selected according to their salinity and temperature preferences in view of the seasonal water quality fluctuations in coastal environments of northern Viet Nam.
It is suggested that financial and technical support be given to RIA No.1 to implement a pilot project on environmental assessment and management of small-scale coastal aquaculture-practices suitable for resource-poor farmers in northern Viet Nam.
It should be noted that the Asian Development Bank recently funded a Coastal Aquaculture Development Study (CADS) for the preparation of both a Coastal Aquaculture Sector Review and a Coastal Aquaculture Action Plan (ADB/MoF, 1996). The recommendations and guidelines proposed by the CADS project team may be helpful in identifying opportunities and requirements for planning and coordination of coastal aquaculture developments, and it is suggested that the documentation developed by the CADS project be considered by relevant research and government institutions of the coastal provinces of northern Viet Nam. Unfortunately, to date there has been no concrete international support to follow-up on the CADS initiatives, and, sofar, no project activities have resulted to provide financial and technical assistance for the implementation of the proposed actions.
