The objectives of this research project are. - The identification and quantification of the major biological processes occurring in Laguna de Bay and their description by mathematical functions. - The development of a short term model of primary and secondary production, fisheries and aquaculture in Laguna de Bay. - The development of a long term ecological model of Laguna de Bay. - The identification and quantification of the interactions between physical geography of the water shed, land use, limnology, fisheries, aquaculture and anthropogeography. - The key activities envisaged are. - Compilation of existing data on the ecology of Laguna de Bay. - Field surveys to elucidate trophic state, primary production and community respiration, and the impact of occasional salt water intrusions on these. - Field surveys and laboratory experiments to investigate the aquatic food chain and interactions between fisheries and aquaculture, using conventional methods and stable isotope tracer techniques. - Investigations on the influence of different N:P ratios on growth and composition of phytoplankton and its digestibility and nutritional value for important fish species. - Geo-ecological survey of Laguna de Bay area and sampling in the major tributaries to identify major impacts of land use on the lake. - Socioeconomic survey of Laguna de Bay area with special reference to fishermen and aqua culturists. - Dynamic modeling of biological processes and socioeconomic conditions.