Stream Ecosystem Model Version 2
Updated to C Sharp with dot net. Includes embedded and downloadable graphics and interactive functions to change initial standing stocks and data in order to parameterize it for other sites.
The link above is documentation that contains a tutorial, examples of standard runs and lists of variables. The tutorial provides the conceptual framework, descriptive information and instructions necessary to run and examine the behavior of three versions of this lotic ecosystem model. The models described are the McIntire and Colby Stream Ecosystem Model and two modified versions of this model that were designed to investigate the process of herbivory and effects of irradiance, food quality, and nutrients on the processes of primary production and grazing. All three models are contained in the Stream Ecosystems program. With each model the user can change initial values of state variables, parameters and input tables (e.g., the irradiance, nutrient, temperature and flow schedules, as well as the allochthonous introductions). Complete mathematical documentation of the three versions of the model is included in this link.
The Stream Ecosystem Model was initially created by McIntire and Colby (1978). Stream and riparian ecosystems are modeled as hierarchical systems of biological processes with physical and chemical processes expressed as driving or control variables. Model structure incorporates abiotic processes in streams as well as community dynamics (McIntire, 1983) and invertebrate functional feeding groupings (McIntire, 1968, 1973; Cummins, 1974). The model was developed for scientific purposes including generating hypotheses, synthesizing field and lab research, evaluating data bases and priorities for future research. The model has also been used to understand temporal dynamics of primary production and instream grazers and for teaching about interactions among instream trophic levels.
The Stream Ecosystem Model has a hierarchical structure that represents dominant biological processes in lotic ecosystems. Stream ecosystems are conceptualized as coupled subsystems involving physical drivers, primary consumption by invertebrates through grazing, shredding, collecting, and microbial decomposition of both autotrophic organisms and detritus. Predation by invertebrate and vertebrates and processes related to the transfer of energy among primary, secondary, and tertiary macroconsumers are also modelled.
The Herbivory Version tracks the successional trajectory and production dynamics of the algal assemblage as well as the response of grazers to corresponding changes in food quality and quantity. This representation also expresses the feedback control that grazing has on successional changes within the algal assemblage.
The Riparian Version of the model is useful for the investigation of effects of riparian zone canopy structure on processes in low-order streams. The Riparian Version has the added feature that photosynthesis and partitioning of primary production among three algal functional groups (diatoms, cyanobacteria, and chlorophytes) are modeled at an hourly resolution instead of daily.
Download and explore Stream Ecosystem Model Version 2
Before Downloading: You will need to save and install a program on your local computer. Be sure that you have administrative rights before you try and install.
Please use the following Acknowledgement:
This program was provided by the HJ Andrews Experimental Forest research program, funded by the National Science Foundation’s Long-Term Ecological Research Program (DEB 08-23380), US Forest Service Pacific Northwest Research Station, and Oregon State University.
Publications using the model include:
McIntire, C. David; Colby, Jonathon A. 1978. A hierarchical model of lotic ecosystems. Ecological Monographs 48(1): 167-190. Pub No. 1910
McIntire, C. D. 1983. A conceptual framework for process studies in lotic ecosystems. In: Fontaine, Thomas D. III; Bartell, Steven M., eds. Dynamics of Lotic Ecosystems. Ann Arbor, MI. Ann Arbor Science Publishers. pg 43-68. Pub No. 4363
McIntire, C. David; Gregory, Stanley V.; Steinman, Alan D.; Lamberti, Gary A. 1996. Modeling benthic algal communities: an example from stream ecology. In: Stevenson, R. J.; Bothwell, M.; Lowe, R. L., eds. Benthic Algal Ecology in Freshwater Ecosystems. Academic Press, Inc. pg 669-704. Pub No. 1528
For more information please contact Sherri Johnson.
Model Documentation for Version 1:
McIntire, C. David. 1990. A tutorial and teaching guide for the use of a lotic ecosystem model. Corvallis, OR: Oregon State University, Department of Botany and Plant Pathology. 271 p. (Pub No. 4362)