1a.Objectives (from AD-416):
Work with USDA-NRCS Plant Materials Centers and various USDA-ARS researchers to develop plant parameters for simulating plant function groups in the western and central U.S. These will be used in the ALMANAC, SWAT, and APEX models as part of the CEAP national assessment for range and pastures.
1b.Approach (from AD-416):
Field measurements at representative sites are continuing in order to develop relevant parameters for plant functional groups. NRCS ecological site data and soils data are being used for model validation and calibration. Model simulation runs are evaluated for reasonableness by comparing with NRCS production values for representative ecological sites.
Using the collected CEAP data from past years, additional rangeland/pastureland plant species have been parameterized. ALMANAC simulations were run using these data, which then were validated with cooperator data. A paper is in the process of being published comparing the simulated grasses to real data. We have concluded a study in which we measured leaf area index, light extinction coefficient for Beer's law, radiation use efficiency, and nitrogen and phosphorus concentrations in well-managed stands of representative plant species for some major plant functional groups in the western U.S. We worked mainly with NRCS Plant Materials Centers, measuring fraction of intercepted photosynthetically active radiation, leaf area index, and dry matter during the growing season in established field plots. These plant parameters for the ALMANAC model were then used to simulate five representative ecological sites in the region. These plant parameters are valuable for simulating individual plant species and plant functional groups. Using these plant parameters, the ALMANAC model will be readily implemented to interpret site monitoring and guide adaptive management approaches. This model and similar models should prove to be valuable tools for Conservation Practice Planning.