1. General Model Information

Name: Barataria-Terrebonne Ecosystem Landscape Spatial Simulation

Acronym: BTELSS

Main medium: aquatic+terrstrial
Main subject: Habitat succession, other
Organization level: Landscape, Ecosystem
Type of model: partial differential equations (finite differences)
Main application: research, decision support/expert system
Keywords: Barataria Basin (Louisiana, USA), deltaic habitats, response to multiple impacts, spatial modeling, Terrebonne Basin (Louisiana, USA), watersheds


Enrique Reyes
Coastal Ecology Institute, LSU,
South Stadium Rd.,
Baton Rouge, LA 70803,
email: ereyes@lsu.edu
Homepage: http://its2.ocs.lsu.edu/guests/wwwcei/staff/enrique.html


Enrique Reyes, Mary L. White, Jay F. Martin, G. Paul Kemp, John W. Day, and Vibhas Aravamuthan


A landscape model was developed to investigate and predict the environmental factors affecting wetland habitat change within the Barataria and Terrebonne basins of coastal Louisiana for a 30-year time scale. The model linked an overland flooding hydrodynamic module, using cells of 100 km2 in size and operating at a 1 hour time-step, and a spatially articulated ecosystem module, resolving habitat type and change for 1 km2 cells in daily time steps. Integration across different temporal and spatial scales was accomplished with interpolation routines and averaging algorithms. Forcing functions included dominant regional processes, such as subsidence, sedimentation and sea-level rise. Hydrologic functions were calibrated against existing climate and hydrologic time-series, while habitat information was compared to maps prepared by the United States Fish & Wildlife Service (USFWS) for 1978 and 1988.
Spatial calibration was done by initializing the landscape pattern of the model to a 1978 USFWS habitat map. After a 10-year simulation, the results were compared against a 1988 USFWS habitat map. Simulated maps had an accuracy of 85 to 90 (out of a maximum of 100), based on a multiple resolution fit algorithm. For validation, the model was initialized with a 1956 USFWS habitat map and the results from a 32-year simulation were compared to the 1988 USFWS habitat map. The landscape model produced reasonable regional agreement, despite the fact that small-scale processes and features were not included. The validation runs produced land loss rates that matched historical trends with an accuracy fit above 75.
The model simulated 30 years into the future, starting in 1988, testing for long-term climate variability under diverse scenarios. Results indicated that weather variability impacts land loss rates more than replication of extreme weather years. Even when extreme dry and wet years were repeated, the model predicted lower land loss when compared to historical records. This is indicative of the ability of the simulated plant communities to adapt to repetitive climatic forcing functions. Yearly maps for the calibration and scenario runs can be seen as color animations on the web site: www.lsu.edu/guests/wwwcei.

II. Technical Information

II.1 Executables:

Operating System(s): UNIX

II.2 Source-code:

Programming Language(s): FORTRAN

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

III.2.2 Output

IV. References

V. Further information in the World-Wide-Web

VI. Additional remarks

Last review of this document by:
Status of the document: Contributed by Enrique Reyes , Mon Jul 31 17:54:19 2000
last modified by Tobias Gabele Wed Aug 21 21:44:40 CEST 2002

Go back to Register of Ecological Models (R E M)