Driving variables for the Century soil organic matter (SOM) model include temperature, precipitation, soil physical characteristics (texture, hydric class, etc.), and land management. Since SOM dynamics in the Century model represent SOM pools that are not measureable, historic driving variables are required to accurately represent SOM dynamics. Therefore, historical land use/land management information is crucial for accurate characterization of SOM pools and dynamics, but this information is often difficult to compile. Gathering historical land use/management information is, thus, the most demanding segment of this research, and will require a substantial amount of time. Additionally, the end product of this research project will be a decision support tool to enable land owners to identify areas most likely to benefit from prairie restoration for both forage production and carbon sequestration. The decision support system produced as a part of this project will not only be a model for a tool that could be applied regionally, but will be a significant step toward that goal.
Field reconnaissance and data collection of model driving variables will commence in January 2001. An initial reconnaissance trip early in the project will be used to assess the topographic and edaphic characteristics of the property and to evaluate special demands for modeling. Reconnaissance will also enable us to verify that mapped conditions are accurate and to interact and exchange information with GIS staff. Model parameterization will begin in earnest immediately following data collection. Collection and analysis of validation data from similar sites will constitute a substantial amount of time; these data are critical since little on-site validation exist. Fine-tuning of model data and validation of data from ancillary sites will culminate in final data analysis and publication and presentation of results to concerned parties.
The primary result of this project will be a series of maps showing our best estimate of soil C content for the entire property, under current management and under a range of restoration scenarios including restoration of the entire property. These maps will be generated using the most state-of-the-art modeling techniques currently available. Data from this modeling effort can also be used to assess potential forage production benefits arising from grassland restoration. Last, and perhaps most importantly, this work will serve as a first step towards development of a decision support system capable of assessing the impacts of grassland restoration on soil carbon for the entire Columbia River Basin. Information about requirements and methods for this type of assessment, potential for C sequestration with varying degrees of restoration effort, and a discussion of the applicability of this work to developing a regional tool for assessing potential for C sequestration will be compiled into a final report for submission upon completion of the project.