pvb soilCmodel wkshp

Modeling Soil Carbon Dynamics in Northern ForestsPaul Bolstad, Jianwu TangUniversity of MinnesotaAlex Friend, USFS: 

Modeling Soil Carbon Dynamics in Northern Forests Paul Bolstad, Jianwu Tang University of Minnesota Alex Friend, USFS

Managing C in Forest Soils: 

Managing C in Forest Soils Current uncertainty in predicting management impacts on northern forest C pools We lack robust, general models that quantify soil C dynamics for important species and ecosystems We are unable to weigh the impacts of competing management regimes at appropriate scales

Forest C Storage: 

Forest C Storage - Three main pools - Unidirectional transfers Production/decomposition balance Autotrophs Detritus Soil O.M.

Carbon Pool Ideograph: 

Carbon Pool Ideograph General behavior applies across a range of species But, specific knowledge on shape, ordinate, and abscissa scales lacking for most species/ecosystems

Component Autotrophic Production and Detritus: 

Component Autotrophic Production and Detritus Leaf Litter Coarse deadwood Dead branches, twigs Alive and dead stumps, coarse and fine roots Leaves Branches Stem sapwood Stem heartwood Bark Flowers, Fruits

Multi-compartment Models: 

Multi-compartment Models

Decomposition Determinants: 

Decomposition Determinants Biotic Factors: Litter quality, litter size/area, decomposers, producer allocation Physical-climatic Factors: Temperature, moisture, nitrogen, soil texture, soil chemistry Barnes et al. 1998 Gholz et al. 2002

Management: 

Management continuous barely continuous barley, +35t/ha Farmyard manure from 1852-1871 continuous barley, +35t/ha farmyard manure each year

Useful Activities: 

Useful Activities Quantify ideographs for specific important northern species and conditions (quaking aspen, sugar maple, red pine) Review and synthesize taxa-specific literature on component growth, decomposition, and organic matter formation rates and functions and relationships Evaluate stand-level modeling approaches and how well they may accommodate specific management activities