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ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Rangeland Resources & Systems Research » Research » Research Project #439424

Research Project: Rangeland Modeling in the Western Great Plains

Location: Rangeland Resources & Systems Research

Project Number: 3012-21500-001-006-S
Project Type: Non-Assistance Cooperative Agreement

Start Date: Jul 1, 2021
End Date: Jun 30, 2024

Develop a user interface for the APEX 1905 version using experiment data from CPER, which will enhance ARS capabilities in model application and improvement on grazing systems.

The Cooperator and ARS will collaborate in the refinement and continuous improvement in the APEX model 1905 version for estimating forage, animal productivity ,and animal intake, providing scenarios for rotational grazing sequences, and evaluating environmental sustainability in western Great Plains rangelands. This interface will be the foundation of a decision tool that can be used by ranchers and land managers for flexible stocking strategies, to evaluate scenarios for sequencing paddocks in rotational grazing, and to assess trends in environmental quality. Gaps in APEX 1905 include: 1) vegetation responses to water stress are inadequate under dry conditions and during wet-dry transition periods, and 2) animal intake of biomass and total digestible nutrients does not respond adequately to weather and soil on a pasture basis. Efforts are need to address these gaps for improving the 1905 version of APEX. Faculty and staff with the Cooperator will lead efforts on these identified gaps.