Wetlands

After commencing with a summary of the current status, importance and productivity of natural wetlands, the chapter reviews the contribution of wetland ecological functions to sustaining vital ecosystem services. Wetlands are vulnerable to a range of anthropogenic pressures, notably land use change, disruption to regional hydrological regimes as a result of abstraction and impoundment, pollution and excessive nutrient loading, the introduction of invasive species and overexploitation of biomass, plants and animals.

Trophic model of the coastal fisheries ecosystem of the west coast of peninsular Malaysia

A preliminary mass-balance trophic model was constructed for the coastal fisheries ecosystem of the West Coast of Peninsular Malaysia (0 - 120 m depth). The ecosystem was partitioned into 15 trophic groups, and biomasses for selected groups were obtained from research (trawl) surveys conducted in the area in 1987 and 1991. Trophic interactions of the groups are presented. The network analysis indicates that fishing fleets for demersal fishes and prawns have a major direct or indirect impact on most high-trophic level groups in the ecosystem.

Trophic model of the coastal fisheries ecosystem in the Gulf of Thailand

The biomass of 40 ecological groups, the diet composition of prey and predators, production/biomass (P/B) and consumption/biomass (Q/B) ratios, and catches were used as basic input to parameterize an Ecopath model of the Gulf of Thailand. Following construction of a mass-balance ecosystem model, a time-dynamic simulation model (Ecosim) was used to simulate the impact of change in fishing effort. This was done using time series data to validate the historic fisheries development in the Gulf of Thailand prior to using the model for forward-looking simulations.

Strengthening governance across scales in aquatic agricultural systems

Aquatic agricultural systems in developing countries face increasing competition from multiple stakeholders operating from local to national and regional scales over rights to access and use natural resources—land, water, wetlands, and fisheries—essential to rural livelihoods. A key implication is the need to strengthen governance to enable equitable decision-making amidst such competition, building capacities for resilience and transformations that reduce poverty.

Solomon Islands national situation analysis

The CGIAR Research Program on Aquatic Agricultural Systems (CRP AAS) was approved by the CGIAR Fund Council in July, 2011. Solomon Islands, one of five countries targeted by the program, began its rollout with a five month planning phase between August and December of 2011. Subsequent steps of the Program rollout include scoping, diagnosis and design. This report is the first to be produced during the scoping phase in Solomon Islands; it addresses the national setting and provides basic information on the context within which the AAS Program will operate.

Socioeconomic and bioeconomic analysis of coastal resources in central and northern Java, Indonesia

Indonesia’s fisheries exports rose from 2 206 t in 1970 to 598 385 t in 1996 with a subsequent export value rise from US$0.69 billion to US$1.78 billion. The surplus in the balance of trade (BOT) was US$1.59 billion in 1996. The fisheries exports were predominantly shrimp, tuna, skipjack and demersal fishes. Large scale fisheries operations are prevalent in the Java Sea. The dominant fishing gear is hook-and-line (40%), gillnet (31%), traps (10%), seine net and lift-net (6%), purse seine (1%), shrimp net with BED (0.04%) and others (6%). The large scale fisheries e.g.

Utilization of wetland ecosystem through fish-crop diversification for enhanced productivity and economic stability for fish-farm community of Indian sub-continent

This paper deals with a number of case studies that were undertaken during the last 8- 10 years in utilizing divergent ‘Tal’ wetland ecosystems (deep, semi-deep, temporary in a range of agro-ecological zones like NAZ, OAZ and Coastal Zone of the region) for the development of integrated management programmes using a range of approaches.

A trophic model of the coastal fisheries ecosystem off the west coast of Sabah and Sarawak, Malaysia

A mass-balance steady-state trophic model of the coastal fisheries ecosystem off the West Coasts of Sabah and Sarawak, Malaysia (10 - 60 m depth) was constructed using the Ecopath software. The ecosystem models were partitioned into 29 ecological/trophic groups. The input values (e.g. biomasses) for selected groups were obtained from the research (trawl) surveys conducted in the area in 1972. The estimated mean trophic level of the fisheries catch for both models is about 3.3.

A trophic ecosystem model of Lake George, Uganda

A trophic model of Lake George, Uganda, Central Africa was constructed using published quantitative and qualitative information on the various biotic components of the lake and the ECOPATH II approach and software. It is shown that the available production and biomass estimates for the various groups in the system are consistent with each other, and that it is possible to make a balanced model of the major trophic interactions in Lake George.

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