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• 1. [Article] Mathematical documentation for a lotic ecosystem model : addendum

  Citation × Citation Citation Abstract Copy Title: Mathematical documentation for a lotic ecosystem model : addendum Author: White, Curtis, U.S. International Biological Program. Coniferous Forest Biome, McIntire, C. David, University of Washington Title: Mathematical documentation for a lotic ecosystem model : addendum Author: White, Curtis, U.S. International Biological Program. Coniferous Forest Biome, McIntire, C. David, University of Washington Close

• 2. [Article] Mathematical documentation for a lotic ecosystem model

  Citation × Citation Citation Abstract Copy Title: Mathematical documentation for a lotic ecosystem model Author: U.S. International Biological Program. Coniferous Forest Biome, Colby, Jonathan Axford, McIntire, C. David, University of Washington Title: Mathematical documentation for a lotic ecosystem model Author: U.S. International Biological Program. Coniferous Forest Biome, Colby, Jonathan Axford, McIntire, C. David, University of Washington Close

• 3. [Article] Report of the aquatic modeling group : round one

  The aquatic modeling group, consisting of Davis, Donaldson, Hall, Higley, Lyford, McIntire, Mullooly, Overton, Strand, Waring, and Warren, met in four 2-hour sessions from July 7 to July 26. The charge ...

  Citation × Citation Citation Abstract Copy Title: Report of the aquatic modeling group : round one Author: Hall, James D., Higley, Duane Lee, McIntire, C. David, University of Washington, U.S. International Biological Program. Coniferous Forest Biome The aquatic modeling group, consisting of Davis, Donaldson, Hall, Higley, Lyford, McIntire, Mullooly, Overton, Strand, Waring, and Warren, met in four 2-hour sessions from July 7 to July 26. The charge to the group was: 1. Define an appropriate internal structure for the aquatic subsystem; 2. Define significant couplings between the aquatic and terrestrial systems; and 3. Begin to evaluate the present program with the above as background. In general, the discussion centered around stream systems, and specifically around the Lookout Creek drainage on the H. J. Andrews Forest, site of most of the Oregon field research. Much consideration. was given to the best means of incorporating data from earlier studies on Berry Creek, the Drift Creek streams (Alsea Watershed Study), and the Oak Creek Experimental Streams into present modeling efforts. Higley is charged with the responsibility of bringing together a listing of the pertinent publications and theses that might be most applicable to this effort. A tentative listing is included with this report. Title: Report of the aquatic modeling group : round one Author: Hall, James D., Higley, Duane Lee, McIntire, C. David, University of Washington, U.S. International Biological Program. Coniferous Forest Biome The aquatic modeling group, consisting of Davis, Donaldson, Hall, Higley, Lyford, McIntire, Mullooly, Overton, Strand, Waring, and Warren, met in four 2-hour sessions from July 7 to July 26. The charge to the group was: 1. Define an appropriate internal structure for the aquatic subsystem; 2. Define significant couplings between the aquatic and terrestrial systems; and 3. Begin to evaluate the present program with the above as background. In general, the discussion centered around stream systems, and specifically around the Lookout Creek drainage on the H. J. Andrews Forest, site of most of the Oregon field research. Much consideration. was given to the best means of incorporating data from earlier studies on Berry Creek, the Drift Creek streams (Alsea Watershed Study), and the Oak Creek Experimental Streams into present modeling efforts. Higley is charged with the responsibility of bringing together a listing of the pertinent publications and theses that might be most applicable to this effort. A tentative listing is included with this report. Close

• 4. [Article] Trophic relation model based on density dependent processes

  "We have developed graphical and logical models for explaining the production of a consumer on the basis of the capacity of an ecosystem to produce that consumer (the productivity of the system for that ...

  Citation × Citation Citation Abstract Copy Title: Trophic relation model based on density dependent processes Author: Warren, Charles E., 1926-, U.S. International Biological Program. Coniferous Forest Biome, University of Washington "We have developed graphical and logical models for explaining the production 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 the age structure of the consumer. These models involve density phenomena occurring at all trophic steps from light and plant nutrients up to and including the particular consumer,as well as trophic pathways in competition with the path leading to this consumer. These density phenomena and pathways can be used to model the productivity of the system for a particular consumer, with the biomass and age structure of the consumer population as the other determinants of its production. We are now developing formal mathematical models based on responses of individual organisms and leading to our empirically and logically derived models. Preliminary mathematical formulations are being used through a computer program to determine whether output relations are logically and empirically confirmed. In addition, data from various sources are being assembled so that we can synthesize an idealized sockeye lake system and an idealized salmonid stream system."--Introduction. Title: Trophic relation model based on density dependent processes Author: Warren, Charles E., 1926-, U.S. International Biological Program. Coniferous Forest Biome, University of Washington "We have developed graphical and logical models for explaining the production 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 the age structure of the consumer. These models involve density phenomena occurring at all trophic steps from light and plant nutrients up to and including the particular consumer,as well as trophic pathways in competition with the path leading to this consumer. These density phenomena and pathways can be used to model the productivity of the system for a particular consumer, with the biomass and age structure of the consumer population as the other determinants of its production. We are now developing formal mathematical models based on responses of individual organisms and leading to our empirically and logically derived models. Preliminary mathematical formulations are being used through a computer program to determine whether output relations are logically and empirically confirmed. In addition, data from various sources are being assembled so that we can synthesize an idealized sockeye lake system and an idealized salmonid stream system."--Introduction. Close

• 5. [Article] Periphyton dynamics in lotic environments : a simulation model

  The simulation model described below is based on the assumption that the periphyton community can be treated as a unit, without a quantitative concern for the dynamics of its many constituent populations. ...

  Citation × Citation Citation Abstract Copy Title: Periphyton dynamics in lotic environments : a simulation model Author: U.S. International Biological Program. Coniferous Forest Biome, McIntire, C. David, University of Washington The simulation model described below is based on the assumption that the periphyton community can be treated as a unit, without a quantitative concern for the dynamics of its many constituent populations. The function statements and parameter estimates incorporated into the model are based on experimental work with laboratory streams and some observational data from Berry Creek Experimental Stream. The approach used here to model the dynamics of periphyton communities in streams is essentially the same approach employed by Jay W. Forrester to model industrial and urban systems. A particular system is identified by establishing a boundary within which the system interactions take place. Level (state) variables and rate (flow) variables are linked together by a complex system of feedback loops and various intermediate concepts (modules), and these components represent the basic structural elements within the boundary. Function statements that represent relation between structural components of the system are written and programmed in some suitable simulation language (for example, MIMIC or DYNAMO). The computer output usually provides numerical values of particular variables and a plot of these values against time. Title: Periphyton dynamics in lotic environments : a simulation model Author: U.S. International Biological Program. Coniferous Forest Biome, McIntire, C. David, University of Washington The simulation model described below is based on the assumption that the periphyton community can be treated as a unit, without a quantitative concern for the dynamics of its many constituent populations. The function statements and parameter estimates incorporated into the model are based on experimental work with laboratory streams and some observational data from Berry Creek Experimental Stream. The approach used here to model the dynamics of periphyton communities in streams is essentially the same approach employed by Jay W. Forrester to model industrial and urban systems. A particular system is identified by establishing a boundary within which the system interactions take place. Level (state) variables and rate (flow) variables are linked together by a complex system of feedback loops and various intermediate concepts (modules), and these components represent the basic structural elements within the boundary. Function statements that represent relation between structural components of the system are written and programmed in some suitable simulation language (for example, MIMIC or DYNAMO). The computer output usually provides numerical values of particular variables and a plot of these values against time. Close