Environmental performance of brackishwater fishponds in Bohol, Philippines
2004
Paquita, A.L.
Environmental performance of the brackishwater fish ponds production systems for milkfish and shrimps in Bohol, Philippines was assessed based on set criteria. This includes 55 extensive fish farms, 28 semi-intensive and 8 intensive production systems. Soil fertility and water quality status of the fish ponds were determined. A structured questionnaire was developed to determine the levels of input used, resource use patterns, productivity, cultural and environmental management practices, adopion of wastewater treatment facilities, knowledge and skills on fish pond production of the operator of each fish farm. The knowledge, perception and attitude towards fishpond production of municipal fishers and fishpond farners were compared. Decision-theoretic evaluation was used to analyze the existing policies affecting the fishpond production. The soils of the fish ponds are slightly acidic to neutral, low in organic matter, deficient in phosphorus an d adequate in potassium. The salinities of water in the fishponds are suitable for milkfish and shrimp production. The dissolved oxygen was below the desired levels for milkfish and shrimps. Majority of the fish ponds produced less or equal to 1.0 ton of milkfish or shrimp per cropping. The semi-intensive fish pond production systems had higher environmental performance than the extensive fish production system. There was no proper fish pond development plan and poor site selection. However, there was continuous use of traditional cultural practices contributed to low ecological and technological viabilities of extensive fish ponds production system. The semi-intensive and intensive fish pond production systems had established environmental management for soil quality, by-products and wastewater, and trained fish pond managers. The municipal fishers had negative perception and attitudes toward brackishwater fishponds development due to indiscriminate conversion of mangroves forest into fishpond, use of persistence pesticides in the fishponds and disposal into the coastal areas of polluted wasterwater during harvest and pond clearing. Environmental policies on environmental impact statement had higher policy outcomes to influence operators of fishpond than policy on toxic and hazardous waste as per revised Philippine Forestry Code and Local Government Code.
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