1 / 21

DAYCENT Simulation of two Contrasted Atmospheric N Deposition Forests

DAYCENT Simulation of two Contrasted Atmospheric N Deposition Forests. Fengming YUAN. 22 June 2007. DAYCENT Model. - issues with previous results. DAYCENT Model. - issues with previous results. DAYCENT Parameterization - Sensitive Parameters. fix.100. damr(1,1) ----

infinity
Download Presentation

DAYCENT Simulation of two Contrasted Atmospheric N Deposition Forests

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. DAYCENT Simulation of two Contrasted Atmospheric N Deposition Forests Fengming YUAN 22 June 2007

  2. DAYCENT Model - issues with previous results

  3. DAYCENT Model - issues with previous results

  4. DAYCENT Parameterization - Sensitive Parameters fix.100 • damr(1,1) ---- • fraction of surface N absorbed by residue • Range: 0.0 to 1.0 • Others: DEC(1), PMCO2(1) , P1CO2a(1)

  5. Model Runs • Mixed conifer forests • Two sites: • High-N site – Camp Paivika: • 7.15 gN/m2/yr (since 1942 ) • Low-N site – Barton Flats/Camp Oscela: • 0.88 gN/m2/yr (since 1942 ) • N deposition rates (gN/m2/yr) : • 0.1, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, and 7.0 • Tree ages: • from 1900 • from 1942

  6. Results • Current N deposition • Questions: • How does ecosystem response in terms of productivity and N cycling? • Would ecosystem reach a new steady state? And if yes, When? • What indicators would be good for so-called forest N saturation, using modeling approach?

  7. Results • Current N deposition • Ecosystem C and N concentration CP1-0.1/BF1-0.1: background N deposition, CP1-71.5/BF1-8.8: current level N deposition assuming forests regenerated in 1900, and, CP2-71.5/BF2-8.8: current N deposition but assuming forests growth in the beginning of depositions.

  8. Results • Current N deposition • Ecosystem N Accumulation and losses CP1-0.1/BF1-0.1: background N deposition, CP1-71.5/BF1-8.8: current level N deposition assuming forests regenerated in 1900, and, CP2-71.5/BF2-8.8: current N deposition but assuming forests growth in the beginning of depositions.

  9. Results • N deposition rates • Objectives: • Critical Loads • Threshold

  10. Results • N deposition rates • Objectives: Critical loads/Thresholds • What indicators? • Highly variable from year to year

  11. Results • N deposition rates • N deposition rate effects on productivity • Mean +/- StDev. Over 1942 ~ 2005

  12. Results • N deposition rates • N deposition rate effects on N accumulations • Mean +/- StDev. Over 1942 ~ 2005

  13. Results • N deposition rates • N deposition rate effects on N mineralization and losses

  14. Results • N deposition rates • N deposition rate effects on N losses

  15. DAYCENT consideration for Landscape Levels

  16. Other factors • Soils, N deposition variability, fire regime, ……. • Soils

  17. Other Factors • Soils, N deposition variability, fire regime, ……. • Soils

  18. Other Factors • Soils, N deposition variability, fire regime, ……. • Can DAYCENT be running at landscape level ? Yes ? • Initial conditions • Output “relay” • Input/parameter file “generator”

  19. Next … • DAYCENT parameterization for CSS • Model parameters for shrub/native grass ? Shrub vs. invasive grasses

  20. Next … • DAYCENT parameterization for CSS ? Shrubs vs. invasive grasses in term of N utilization (Padgett & Allen, 1999. Plant Ecology, 144: 191-193)

  21. Next … • DAYCENT parameterization for CSS ? Shrubs vs. invasive grasses in term of N utilization N Uptake Capacity Vs. N concentration (Padgett & Allen, 1999. Plant Ecology, 144: 191-193)

More Related