Northwest Advanced Renewables Alliance Douglas-fir biomass and nutrient removal under varying harvest intensities designed for co-production of timber and biofuel Kristin Coons, Doug Maguire, Doug Mainwaring, Andy Bloom, Rob Harrison, and Eric Turnblom

Background Biofuel is a viable, renewable alternative to fossil fuels. The leading national level assessment proposes displacing 30% of the petroleum consumed in the U.S. Biofuel produced from forests comprises 50% of energy derived from all biomass in the U.S. The majority of aboveground biomass in the PNW is Douglas- fir.

Outline I.Background II.Objectives III.Hypotheses IV.Study Sites V.Methods VI.Preliminary Results

Northwest Advanced Renewables Alliance

Knowledge Gap Current biomass equation insufficiencies: ­ Based on only diameter at breast height (DBH) ­ Developed on stands with limited range in stand density, height-diameter combination, and stem profile ­ Lack of inclusion of above- and below-ground components ­ Not applicable on a scale pertinent to biofuel production. Implications of differing types and intensities of biomass harvest to long term site productivity are not known.

Objectives I.Quantify nutrient and biomass contents of the major tree components and understory vegetation II.Model of biomass and nutrient distribution in stands managed under varying silvicultural regimes. III.Infer or estimate the long term implications to site productivity

Hypotheses H 1: Large portions of the above-ground biomass can be removed for biofuel production without declines in long-term site productivity. ­ H 1a : Whole tree harvest (aboveground) ­ H 1b : Stem only harvest ­ H 1c : Stem with other clean chip components harvest

Leaching Atmospheric Deposition Uptake Rate Mortality Rate Decomposition Rate Cation Exchange Capacity Nutrient Model Weathering Understory vegetation

Tree Sampling Installations 4 Stand Management Cooperative (SMC) TYPE 1 installations 4 Vegetation Management Research Cooperative (VMRC) Large trees from operational units

Installation & plot selection for Destructive Tree Sampling PC ET RR LF

Data Sources for Biomass Equations

Individual Tree Stem Mass Double Bark Thickness Equation -Maguire and Hann 1990 Inside Bark Volume Taper Equation -Walter and Hann 1986 Sapwood Taper Equation -Maguire and Batista 1996 Mass estimated using volume and weighted average density

Individual Tree Branch and Foliage Mass Live branches (X) = a 0 (BrD) a1 (RHACB) a2 (DINC) a3 Dead Branches (X) = b 0 (BrD) b1 (RHAB) b2 X = Foliage or Wood mass (g) BrD = Branch diameter (mm) DINC = Depth into crown (m) RHACB = Relative height above crown base (m) RHAB = Relative height above tree base (m) Branch Diameter (mm)

Whole tree biomass models tested…… Linear Models Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(ht) + β 3 Ln(cl) + β 3 (cl) + β 4 (cbl) + β 4 Ln(cbl) Non-Linear Models B = β o dbh β1 B = β o dbh β1 * ht β2 B = β o dbh β1 * ht β2 * cl β3 B = β o dbh β1 * ht β2 * e β3*cl B = β o dbh β1 * ht β2 * cbl β3 B = β o dbh β1 * ht β2 * e β3*cbl Weights – 1 / dbh – 1 / dbh 2 – 1 / (ht * dbh 2 ) – 1 / (ht 2 * dbh 2 ) – 1/ (ht * dbh 2 ) 2 – 1 / (cl * dbh 2 ) – 1 / (cl 2 * dbh 2 ) – 1/ (cl * dbh 2 ) 2

*D = DBH (cm), H= Height (m), CL = Crown length, CBL=Clear bole length (m) Site Independent Equations

Relationship between dbh, height, and total biomass for the SMC Type 1 sites, constructed with a site- independent model. *Crown length fixed at 14 (m) and clear bole length at 12.5(m)

Proportion of biomass (kg/ha) by component

Average N, P, K, Mg, Ca and S by site

Average nitrogen by component on SMC TYPE 1 sites

Preliminary maximum nutrient removal by harvest type

Any Questions or Comments?

Distribution of Forest residuals with logging systems in Western Oregon Photo: Francisca Belart Photo: glogging.com/logging/ shovel-logging.htm WT- Cable logging WT- Shovel logging

Nutrient Concentration Variability

Component biomass(%) averaged over treatment type

Component biomass averaged by site over treatment types presentation title

Change in Average Nutrient Concentration with Height presentation title

More Specific Plot Treatments presentation title Installation Site Index yrs)Initial stems/ac Treatment ISPA: RD55-->RD35, RD55-->RD40, RD60-->RD40, – Ostrander Road ISPA/2: RD55-->RD35, no further thinning ISPA/4, no thinning ISPA: RD55-->RD35, RD55-->RD40, RD60-->RD40, East Twin90700 ISPA/2: RD55-->RD35, no further thinning ISPA/4, no thinning ISPA: RD55-->RD35, RD55-->RD40, RD60-->RD40, Roaring River ISPA/2: RD55-->RD35, no further thinning ISPA/4, no thinning ISPA: RD55-->RD35, RD55-->RD40, RD60-->RD40, Toledo ISPA/2: RD55-->RD35, no further thinning ISPA/4, no thinning

Models Tested……… Linear Models Ln(B) = β 0 + β 1 Ln(dbh) Ln(B) = β 0 + β 1 Ln(ht) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(ht) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(cl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 (cl) Ln(B) = β 0 + β 1 Ln(ht) + β 2 Ln(cl) Ln(B) = β 0 + β 1 Ln(ht) + β 2 (cl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(ht) + β 3 Ln(cl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(ht) + β 3 (cl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(cbl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 (cbl) Ln(B) = β 0 + β 1 Ln(ht) + β 2 Ln(cbl) Ln(B) = β 0 + β 1 Ln(ht) + β 2 (cbl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(ht) + β 3 Ln(cbl) Ln(B) = β 0 + β 1 Ln(dbh) + β 2 Ln(ht) + β 3 (cbl) Non-Linear Models B = β o dbh β1 B = β o dbh β1 * ht β2 B = β o dbh β1 * ht β2 * cl β3 B = β o dbh β1 * ht β2 * cbl β3 B = β o dbh β1 * ht β2 * e β3*cl B = β o dbh β1 * ht β2 * e β3*cbl Weights 1 / dbh 1 / dbh 2 1 / (ht * dbh 2 ) 1 / (ht 2 * dbh 2 ) 1/ (ht * dbh 2 ) 2