Download - Influence of greater Nitrogen Deposition in Missoula, MT Anne Trainor Exercise 3 October 2, 2007
Influence of greater Nitrogen Deposition in
Missoula, MT
Anne TrainorExercise 3
October 2, 2007
Introduction
Substantial increase of nitrogen deposition since the industrial boom large impacts on forested ecosystems.
Objective: Examine how a significant increase in
nitrogen could influence annual and seasonal nutrient cycling dynamics within an evergreen forest.
Study System
Missoula, MT Meteorological Data: 1950-1993 1 m Loamy Soil
30% sandy, 50% silt, 20% clay Evergreen Needleleaf system
Used all defaults
Modeling
Biome-BGC (version 4.1.2) Carbon levels constant at default value
(294.842 ppm) Consisted of 3 runs for 88 years
A) Spin up: Default pre-industrial nitrogen level (0.0001 kgm2yr1)
B) Typical Nitrogen: Based off previous Spinup ran simulation with default pre-industrial nitrogen level (0.0001 kgm2yr1)
C) Increased Nitrogen: Based off original Spinup ran simulation with Nitrogen increased to 0.005 kgm2yr1
Methods
Selected a consecutive dry and wet year to compare extremes
1980 and 1981
1973 and 1974
Relevant Variables ModeledVariables
Annual Daily
Maximum LAI LAI
NPP NPP
GPP Soil carbon fluxes (SoilC 1-4)
Evapotranspiration
Litter stores (LitterC 1-4)
Leaf water potential