1 / 7

Nitrogen Limitation and Terrestrial C Storage

Nitrogen Limitation and Terrestrial C Storage. Christine L. Goodale Cornell University clg33@cornell.edu. NACP Meeting San Diego CA February 17-20 2009 30 Participants. Adrien C. Finzi Boston University afinzi@bu.edu.

ardara
Télécharger la présentation

Nitrogen Limitation and Terrestrial C Storage

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nitrogen Limitation and Terrestrial C Storage Christine L. Goodale Cornell University clg33@cornell.edu NACP Meeting San Diego CA February 17-20 2009 30 Participants Adrien C. Finzi Boston University afinzi@bu.edu

  2. C x N InteractionsA Missing Component of the Predicted Terrestrial-C Sink Cramer et al. (2001) DGVM Hungate et al. (2003)

  3. N limitation constrain ecosystem responses to elevated CO2?a continuum of responses Can the current generation of ecosystem models accurately represent the variation in response for the right reasons? POP- EUROFACE Rhinelander Duke slow or no loss of stimulation ORNL Texas Tunnel Florida Scrub Oak Minnesota BioCON Flakaliden, Boreal Sweden SETRES, SC Costal Plain rapid loss or no stimulation

  4. atmospheric N deposition may reduce N limitation to terrestrial C uptakeeffects are disputed holland et al., 2005, ecol. appl.

  5. what is the relationship between atmospheric N deposition and primary production? magnani et al., 2007, nature nadelhoffer et al. 1996, nature

  6. Science Challenges: Limited (but growing) engagement of the C cycle science community A. stoichiometric constraintsB. developing models of belowground dynamics i. N supply not solely a function of climate ii. belowground C allocation drives N cycling No real time or automated measurements of N cycling variables (except remotely sensed foliar [N]) Resource intensive measurements (time & money) limit spatial and temporal extent of available data Significant uncertainties in the effects of N deposition on NEP

  7. Agenda Item for NACP Community Explicitly incorporate the biogeochemical cycle of N into discussions and measurements of the terrestrial C cycle • Development of databases for model development and calibration • Model-data intercomparison activities use existing, detailed experiments to test model C-N interactions - 15N tracer experiments to model dynamics of N dep. correctly - LIDET studies to assess model N mineralization dynamics • Develop standard measurements of N pools at carbon observation sites A. Foliar N at existing sites -spectral methods for high frequency measurements on time scales comparable with C flux measurements B. Leverage existing biometric measurements by sending samples for C & N analysis • Develop next-generation C-N experiments to aid model development

More Related