ARS | Publication request: Quantifying Annual Aboveground Net Primary Production in the Intermountain West

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 5, 2009
Publication Date: February 7, 2010
Citation: Finzel, J., Weltz, M.A., Seyfried, M.S., Launchbaugh, K., Kiniry, J.R. 2010. Quantifying Annual Aboveground Net Primary Production in the Intermountain West [abstract]. Society for Range Management and Weed Science Society of America Annual Meeting Program Guide. P C-27.

Technical Abstract: As part of a larger project, methods were developed to quantify current year growth on grasses, forbs, and shrubs. Annual aboveground net primary production (ANPP) data are needed for this project to calibrate results from computer simulation models and remote-sensing data. Measuring annual ANPP of annual and perennial grasses and forbs is relatively straightforward. Once the growing year starts any green vegetation is considered current year growth and can be clipped and weighed to determine annual ANPP. Measuring current year growth on shrubs is more challenging because shrubs produce new growth from standing live biomass. The challenge of quantifying new growth on shrubs is two-fold; distinguishing new growth from old growth and then accurately measuring and quantifying that new growth. This poster reviews methods for quantifying current year growth on grasses, forbs, and shrubs, with a special emphasis on shrubs. It includes a description of measuring leaf area index using a Ceptometer (Decagon, Pullman, WA) and a laser-point frame and an evaluation of both instruments performance when applied to shrubs.