Trophic relation model based on density dependent processes

We have developed graphical and logical models for explaining theproduction of a consumer on the basis of the capacity of an ecosystem
to produce that consumer (the productivity of the system for that consumer),on the basis of the biomass of the consumer, and on the basis of theage structure of the consumer. These models involve density phenomenaoccurring at all trophic steps from light and plant nutrients up toand including the particular consumer,as well as trophic pathwaysin competition with the path leading to this consumer. These densityphenomena and pathways can be used to model the productivity of thesystem for a particular consumer, with the biomass and age structureof the consumer population as the other determinants of its production.
We are now developing formal mathematical models based on responsesof individual organisms and leading to our empirically and logicallyderived models. Preliminary mathematical formulations are being usedthrough a computer program to determine whether output relations arelogically and empirically confirmed. In addition, data from varioussources are being assembled so that we can synthesize an idealizedsockeye lake system and an idealized salmonid stream system.