|Title||Preliminary steady-state nitrogen models of a wetland ricefield ecosystem with and without fish|
|Year of Publication||1993|
|Authors||Lightfoot, C, Roger PA, Cagauan AG, Cruz CRD|
|Series Editor||Christensen, V, Pauly D|
|Number of Pages||56-64|
|Keywords||Agropisciculture, Cyprinus carpio, ecopath ii, ECOSYSTEMS, Freshwater, modelling, Oreochromis niloticus, Q1 01585 Plant culture, Q3 01585 Plant culture, Rice field aquaculture|
Rice and fish are the most important food sources in Asian diets. Up to now the supply of rice and fish have come from different sources. The traditional practice of catching wild fish in ricefield is insignificant today. Recent investigations indicate, however that integrated rice-fish systems offer possibilities of increasing rice yield by as much as 15% and at the same time harvesting fish up to 500 kg ha super(-1) every rice crop. Modern rice production has become heavily dependent on insecticides. Through the integration of fish in rice paddies the possibility exists for reducing insecticides use. Similarly, chemical fertilizers could be partially substituted with farm by-products fed to the fish. To improve our understanding of ecological interactions in rice-fish systems, ECOPATH II have been used to construct initial models of rice systems, one with and one without fish. While these preliminary models were constructed from limited field data, they do provide indicators for critical field measurements and experimentation. Future models will assists in the development of guidelines for optimum management of rice-fish integrated systems.