101747 Synthesizing Rangeland Processes for Decision-Making Using the Gpfarm-Range Model.

Poster Number 455-820

See more from this Division: ASA Section: Climatology and Modeling
See more from this Session: Honoring the Contributions of Laj Ahuja: Building Bridges Among Disciplines By Synthesizing and Quantifying Soil and Plant Processes for Whole Systems Modeling Poster

Wednesday, November 9, 2016
Phoenix Convention Center North, Exhibit Hall CDE

Allan A. Andales, 1170 Campus Delivery, Colorado State University, Fort Collins, CO and Zhiming Qi, Department of Bioresource Engineering, Macdonald Campus, McGill University, Sanite-Anne-de-Bellevue, QC, Canada
Poster Presentation
  • Andales&Qi 2016 GPFARM-Range poster.pdf (636.2 kB)
  • Abstract:
    A modeling approach that assesses impacts of alternative management decisions prior to field implementation would reduce decision-making risk for rangeland and livestock production system managers. The Great Plains Framework for Agricultural Resource Management – Rangeland model (GPFARM-Range) was developed as a decision support tool that synthesizes field-scale hydrology, forage, carbon-nitrogen, and cattle processes. The model was shown to have strategic and tactical functionality for predicting forage production (77% – 94% explained variability of with-in-season forage biomass) and selecting cattle stocking rates in Northern mixed-grass prairie. The model was shown to give acceptable simulations of soil organic carbon and nitrogen (< 5% relative root mean square error, RRMSE during calibration; < 20% RRMSE during validation). Also, the model adequately simulated the effects of elevated [CO2] (720 ppm in field enrichment experiments on shortgrass steppe, 1997-2001) on both peak standing crop and soil water (within ± 10% bias; index of agreement > 0.70). GPFARM-Range captured observed trends in increased C3 grass biomass and reduced plant transpiration under elevated [CO2]. The model synthesizes the complex interactions among rangeland management, climate, forage, and livestock production. Contributions of Dr. Lajpat R. Ahuja in facilitating multi-disciplinary collaborations to achieve these synthesis results are highlighted.

    See more from this Division: ASA Section: Climatology and Modeling
    See more from this Session: Honoring the Contributions of Laj Ahuja: Building Bridges Among Disciplines By Synthesizing and Quantifying Soil and Plant Processes for Whole Systems Modeling Poster