The EC Water Framework Directive and monitoring lakes in the Republic of Ireland

The authors of the article explore and discuss the effects of implementing the EC Water Framework Directive (WFD) in the Republic of Ireland. They also summarise some of the findings from a survey of 31 lakes sampled regularly between March 1996 and December 1997. The lakes were sampled regularly for a range of physico-chemical and biotic variables that probably would be important for monitoring programmes implemented under the WFD. The authors discuss problems of monitoring lake types with varying seasonal patterns.

A preliminary classification of lake types in Northern Ireland

The EC Water Framework Directive (WFD) introduces the concept of the ecological status of surface waters. The WFD requires that water bodies within an ecoregion are divided into waterbody "types" or "ecotypes". The waterbody type is determined by physico-chemical descriptors. A group of representatives from two government environmental agencies (Environment and Heritage Service and the Industrial Research and Technology Unit) and the two universities (Queen's University Belfast and the University of Ulster) in Northern Ireland, has been established to develop methods for measuring the ecological status of lakes, for the purposes of the WFD. The work here is that contributing to the first objective classification into waterbody types.

A new synoptic survey of Northern Ireland lakes: sampling from the air

Northern Ireland has approximately 1670 lakes, which cover 4.4% of the land surface. However, most of the water area is accounted for by the large lakes such as Lough Neagh (385 km2) and Lower Lough Erne (109.5 km ). The majority of lakes are less than 100 hectares in area. They tend to be distributed towards the south and west of the Province, where extensive drumlin swarms are rich in small waterbodies. In 1988-1991, 610 of the 708 lakes between one and 100 hectares were sampled by the Northern Ireland Lake Survey. The objective was to assess their conservation status based on their aquatic macrophyte flora, but in addition to extensive plant surveys, the water of each lake was analysed for a range of chemical variables. This article reports on a full-scale survey carried out in early March 2002. The survey was taken with help of two helicopters. The authorise summarise the results of the chemical analysis of the survey.

Factors influencing the downstream transport of sediment in the Lough Feeagh catchment, Burrishoole, Co. Mayo, Ireland

Research laboratories in the Burrishoole catchment have been the focus of salmonid research since 1955. One aspect of the research has been to monitor the number of salmon and sea trout migrating to sea as smolts and returning to the catchment as adults. In the early 1990s it became clear that the smolt output from the catchment had declined over the previous two decades. At about the same time the presence of fine particles of peat silt in the hatchery became increasingly apparent and led to a higher incidence of mortality of young fry. These observations and management difficulties led to a study of silt transport in the surface waters of the catchment, which is described in this article. The authors describe geology, soils, climate and hydrology of Burrishoole before examining the sediment deposition in Lough Feeagh.

Modelling soil erosion and transport in the Burrishoole catchment, Newport, Co. Mayo, Ireland

The Burrishoole catchment is situated in County Mayo, on the northwest coast of the Republic of Ireland. Much of the catchment is covered by blanket peat that, in many areas, has become heavily eroded in recent years. This is thought to be due, primarily, to the adverse effects of forestry and agricultural activities in the area. Such activities include ploughing, drainage, the planting and harvesting of trees, and sheep farming, all of which are potentially damaging to such a sensitive landscape if not managed carefully. This article examines the sediment yield and hydrology of the Burrishoole catchment. Flow and sediment concentrations were measured at 8-hourly intervals from 5 February 2001 to 8 November 2001 with an automatic sampler and separate flow gauge, and hourly averages were recorded between 4 July 2002 and 6 September 2002 using an automatic river monitoring system [ARMS]. The authors describe the GIS-based model of soil erosion and transport that was applied to the Burrishoole catchment during this study. The results of these analyses were compared, in a qualitative manner, with the aerial photography available for the Burrishoole catchment to see whether areas that were predicted to contribute large proportions of eroded material to the drainage network corresponded with areas where peat erosion could be identified through photo-interpretation.

Socio-economic implications of the fish export trade on the fishers and fisheries of Lake Victoria in Uganda

The purpose of this study was to investigate the implications of the fish export trade on the fishers and the fisheries resources of Lake Victoria, Uganda with respect to sustainability. Eight fish processing factories and ninety fishers were qualitatively investigated. Socio-economic characteristics of fishers and the economic characteristics of fish factories formed a basis for the analysis. Results of the research indicate that there is a relationship between the growth in fish export trade, particularly the growth in industrial fish processing (for export) and declining fisheries resources of the lake. However, whether or not that impact is positive or negative, and to what extent there is an impact, is highly dependent upon the underlying socio-economic considerations of the fishers to the process. The fish-ban imposed by the European Union countries was particularly decried by fishers and factory owners as the main cause for the present poverty among the fishers. Fundamentally, several conflicting issues: ecological, physical and economic activities are a threat to the sustainability of the Lake Victoria fisheries, and for all that depend on and interact with the lake. There is urgent need to address the immediate issue of the growing riparian population and the global fish trade, to educate and train all the relevant actors in appropriate fisheries management techniques. Attitudes of fishers towards the fish factory developments are positive and this is a way forward for co-management for the sustainability of the fisheries resource.

Economic assessment of shrimp (Penaeus monodon) hatchery industry in Panay Island, Philippines

Results of the economic assessment of shrimp hatchery industry in Panay Island, Philippines are presented. In order to ensure continuous viability of hatcheries, the critical areas of concern are: financing of operating capital and improvement of facilities; collective marketing efforts through cooperatives; updating of technology especially in disease prevention and control; and diversification strategies.

Length-weight relationship of small pelagic fish species of the southeast and South Brazilian Exclusive Economic Zone

The length-weight relationship (LWR) parameters of 23 small pelagic fish species (belonging to 13 families) from the south-southeast Brazilian Exclusive Economic Zone in 1996 and 1997 are presented. The b values varied between 2.72 and 3.53. The samples for this study were collected during hydroacoustic surveys covering an area of 700 000 square km.

Economic exploitation in the Philippine small pelagic fishery and implications for management

Causes and impact of the Philippine small pelagic fishery sector problems are presented together with the proposed solutions from fisheries and external sectors. The results of the biological and economic analysis of the small pelagic fishery in the Philippines lead to two conclusions: First, small pelagic fish stocks are subjected to levels of fishing effort far beyond that necessary to generate Maximum Sustainable Yield (MSY) let alone Maximum Economic Yield (MEY). Second, and as a result, both sectors are sustaining economic losses (negative economic rents) implying inefficiencies in the use of labor and capital in the small pelagic fishery. Solutions to the problems of overexploitation will rest not only within the fishery sector, but, more importantly, in sectors outside its traditional realm. The underlying causes of fisheries resource over exploitation are also discussed.

A Low-level Geographic Information System for coastal zone management, with application to Brunei Darussalam. Part II:: Economic analysis of trawling in Brunei Darussalam

Economic analysis of the trawl fishery of Brunei Darussalam was conducted using cost and returns analysis and based on an economic survey of trawlers and B:RUN, a low-level geographic information system. Profitability indicators were generated for the trawl fleet under various economic and operational scenarios. The results show that financial profits are earned by trawlers which operate off Muara, particularly those with high vessel capacity, and that these profits could be further enhanced. On the other hand, a similar fleet operating off Tutong would generate profits due mainly to high fish biomass. Trawling operations offshore are deemed financially unfeasible. Incorporating realistic opportunity costs and externalities for existing trawl operations off Muara results in economic losses.

Seaweed-based economic activities in Lombok and Bali, Indonesia

Seaweed production is an important secondary, activity for fishers in eastern Indonesia. In Lombok and Bali, however, it is a major enterprise involving whole village communities in a range of activities from trading to tourism.

Economic seaweed resources and their management in eastern Indonesia

The article focuses on the economic seaweed resources and production in eastern Indonesia and how the fishers in the country adjust their system in managing the resources. Particular attention is given to seaweed which can be used as materials for producing carageenan and agar; most carrageenophyte species explored in eastern Indonesia belong to the genera Kappaphycus and Eucheuma; and seaweeds that produce agar belong to families Gelidiaceae and Gracilariaceae.

Economic incentives for water resource management in the Pak Phanang river basin of southern Thailand

The study examines the existing water allocation methods and other policies that provide constraints or incentives for the most efficient use of water resources. Given the production condition of the local people, and the technical and physical attributes of water resources, the principal hypothesis of this study is that the benefits obtained from fresh water resources in the study area can be improved through better resource management.

Comparison of some traits of economic importance in tilapias (Orechromis niloticus and Sarotherodon galilaeus) with particular reference to their culture in Ghana

This study was conducted to determine which of the two major tilapia species in freshwater capture fisheries in Ghana, Oreochromis niloticus or Sarotherodon galilaeus, is more suitable for breed improvement and pond culture. It compares traits of economic importance, including seed output, specific growth rate, survival and sex ratios following androgen sex reversal. The results of the study showed that the aquaculture potential of S. galilaeus compares favorably with that of O. niloticus. However, S. galilaeus may be preferred because the males and females have an equal growth rate, which allows for manual sorting to raise both sexes in monosex culture, an inexpensive appropriate technology that an ordinary smallscale fish farmer can apply.