|Green, Bartholomew - Bart|
Submitted to: Global Aquaculture Advocate
Publication Type: Trade Journal
Publication Acceptance Date: 8/1/2001
Publication Date: 8/1/2001
Citation: WARD, G.H., GREEN, B.W. ASSESSMENT OF CARRYING CAPACITY FOR SHRIMP AQUACULTURE BY THE USE OF MATHEMATICAL MODELS. GLOBAL AQUACULTURE ADVOCATE. 2001.VOL 4(4)P.69-70.
Technical Abstract: Carrying capacity refers to the maximum development of shrimp farming that a watercourse can accommodate without excessive water quality degradation. Carrying capacity is limited by the natural water quality of a system and any other sources of contamination. It includes not only the aerial extent of shrimp farms, but also their density and geographical distribution along ga watercourse. Of particular concern are shrimp-farming industries established on estuary watercourses, whose exchange with the sea may be so constrained that the carrying capacity is substantially less than the potential farm development based upon suitable land and infrastructure. A carrying capacity model was developed for shrimp farming in Honduras. This industry is mainly situated on small tributary estuaries in the eastern segment of the Gulf of Fonseca. These are longitudinal systems, primarily flushed by tides. Especially during the dry season these channel estuaries shave limited renewal of water from the adjacent gulf, despite the large tidal excursions. Application of modeling determined that water quality is most stressed during the dry season, and that the natural water quality is depressed by organics flushed from the watershed and the tidal flats into the estuary channels. Thus it was predicted that water quality would decline with distance upstream, evidenced by depressed dissolved oxygen concentrations, even without the complicating effect of shrimp pond drainage, and therefore shrimp farms situated on the far upstream reaches of the estuaries would exert particularly strong influences on local estuary quality. The presence of a zone of substantially reduced dissolved oxygen in the upper reach of these estuaries was confirmed by field