Author
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TUGEL, ARLENE - USDA-NRCS |
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BROWN, JOEL - USDA-NRCS |
Submitted to: Washington National Cooperative Soil Survey Work Planning Conference
Publication Type: Proceedings Publication Acceptance Date: 6/25/2001 Publication Date: 6/25/2001 Citation: TUGEL, A.J., BROWN, J.R. STATE AND TRANSITION ECOSYSTEM MODELS: APPLICATION TO SOIL SURVEY AND DYNAMIC SOIL PROPERTIES DATABASES. PROCEEDINGS OF THE WASHINGTON NATIONAL COOPERATIVE SOIL SURVEY WORK PLANNING CONFERENCE. 2001. P. 194-201. Interpretive Summary: Interpretive summary not required for proceedings. Technical Abstract: Arid and semiarid rangelands are hypothesized to function as nonequilibrium systems. Models that capture these nonequilibrium dynamics at the ecological site level are called state and transition models (STMs). Through the literature, we examined the changes in soil properties that occurred as a result of changes in vegetation on a sandy loam upland site in the shrublands of south Texas. Clay content, bulk density, pH, carbon and nitrogen are compared for herbaceous plant communities and mesquite states. Dynamic soil property data is needed in rangeland management for assessment, prediction and monitoring. State and transition models can provide a database framework for soil characteristics according to soil-plant relationships as well as soil-management interactions that affect soil properties and plant communities over time and at multiple scales. Developing a soil information system or enhancing the National Soil Information System (Natural Resources Conservation Service) for dynamic soil properties will require the reinterpretation of existing data and new observations and experiments. Measurable soil properties that reflect ecological processes and the functional capacity of rangeland soils should be included. |