northwest advanced renewables alliance how do residual biomass removals affect long- term forest...
Post on 13-Dec-2015
217 Views
Preview:
TRANSCRIPT
Northwest Advanced Renewables Alliance
How do residual biomass removals affect long-term forest productivity?:
Long-term Soil Productivity (LTSP) studies
Scott M. Holub, Ph.D.Silviculture Research Scientist
Weyerhaeuser CompanySpringfield Oregon
February 18, 2015MOSS Imagine Tomorrow Webinar
2
OBJECTIVE OF TODAY'S PRESENTATION
• Briefly describe Weyerhaeuser Company and the processes we use to achieve sustainable site productivity and meet stewardship objectives to:
minimize soil erosion and harmful soil disturbance
maintain or enhance organic matter and soil nutrition
• Present information about two studies looking at the effects of biomass removal on Long Term Soil Productivity.
WEYERHAEUSER IS ONE OF THE WORLD’S
LARGEST PRIVATE FOREST LANDOWNERSAND HARVEST ONLY A SMALL PERCENTAGE EACH YEAR
~2.5 million acres in western Oregon and Washington
6
WEYERHAEUSER FORESTRY
Weyerhaeuser Forestry has resource strategies for:
- Forest Products- Water Quality- Wildlife Habitat
-Soil Productivity
7
WEYERHAEUSER FORESTRY
•Commitment to sustainable forestry:
Soil is an integral part of the forest – no crop can be managed sustainably without considering the soil that supports it.
8
Organic Matter/Soil Nutrient - Management Principles
• Conserve organic matter/nutrients throughout the managed forest cycle
• Balance nutrient inputs/outputs through successive rotations
• Follow Best Management Practices
9
SOIL & NUTRIENT MANAGEMENT PRINCIPLES
Loss of topsoil and associated litter layers can reduce soil productivity potential by:
•Reducing organic matter - reduces moisture holding capacity/infiltration
•Relocating nutrients -- leading to localized areas of low soil fertility
10
Soil aeration and macro-pore space are critical determinants of soil productivity:
–Soil compaction can be detrimental, neutral, or beneficial depending on the level of pore space and texture of the undisturbed soil and the degree of macro-pore space
–Disruption of pore space continuity can also impact water movement
SOIL & NUTRIENT MANAGEMENT PRINCIPLES
11
Soil productivity potential can be enhanced:
•Compacted soil layers -- soil cultivation
•Nutrient deficiencies -- nutrient amendments
SOIL & NUTRIENT MANAGEMENT PRINCIPLES
13
WHAT IS NARA?
NorthwestAdvancedRenewablesAlliance
www.nararenewables.org
NARA is the name given to the group of organizations involved in a $40 million biofuel grant from USDA AFRI.
Goal:Convert Douglas-fir woody biomass to jet fuel.
14
ENVIRONMENTAL SUSTAINABILITYPart of NARA’s Mission:
… meet the high environmental standards of the Pacific Northwest.
15 | 8/13/2014
SOIL PRODUCTIVITY/SLASH REMOVALConcern:Removing slash removes nutrients and
compacts soil.
Question:Does slash harvest for biofuel feedstock affect future site growth capacity?
Implications: Sustainability / Carbon neutrality / Policy
16
LONG TERM SOIL PRODUCTIVITY NETWORK
Map Credit: Andy Scott, USFS
Regional Studies in Coastal
Douglas-fir
Matlock, WAFall River, WA
Molalla, ORNARA LTSP
17
NARA LTSP TIMELINE
2012 – Site indentified/plotted – 83 acres near Springfield, Oregon. 28 1-acre plots.Soil nutrients (June/July) / Pre-harvest tree, etc. measurements (Sept/Oct).
2013 – Harvest (Feb-May) / Biomass removal and compaction treatments (May-July). Install weather instruments and soil water collection (July-Sept). Fence site (Nov) 2014 – Plant seedlings, initial tree measurements (March/April).First season tree measurements / 15 year measurements at Fall River LTSPContinue monitoring site conditions / Grad student projects.
2015 – Second-year tree measurements (Oct). Report drafted by mid-2016.
2016-beyond Monitor site conditions, measure trees at year 5, 10, 15, etc.
18
CompactionOM Removal
C0 – No compaction C1 - Moderate compaction
OM0 – Bole only OM0 C0Boles removed /No compaction
OM0 C1Boles removed /Moderate compaction
OM1 - Boles and crowns removed
OM1 C0Boles & crowns removed /No compaction
OM1 C1Boles & crowns removed /Moderate compaction
OM2 - Boles, crowns, forest floor removed
OM2 C1Boles, crowns & forest floor removed /Moderate compaction
* F&G = + mid-rotation fertilization
NARA LTSP Treatments-L
evels
of
Sla
sh
Rem
oval-
A C
B D/F*
E/G*
19
NARA POST-TREATMENT AERIAL PHOTO
Photo taken October 2013 – Post treatment – looking west across the north part of the study
Total Tree Removal
No Forest Floor
Bole only Removal
20
NARA LTSP - TREATMENT LAYOUT
Bole only / No compTotal Tree/ No compTotal Tree/ Compacted
Bole only/ CompactedForest Floor/ CompTotal Tree/ Compacted*Forest Floor/ Comp*
* With mid-rotation fertilization
21
NARA POST-TREATMENT CONDITIONS
Good separation. Pre-harvest range also shown
A
B
C
D/F
E/GPre-harvest range
22
INSTRUMENTATION - NARA LTSP
22
• Standard Weather Stations (2)– Harvested area – Forest
Every plot (28) + 4 in Forest:• Soil moisture and temperature
– 10, 20, 30, 100 cm
• 15 cm Air temperature and Relative Humidity
23
COLLABORATION - NARA LTSP
23
• Jim Rivers / Matt Betts– OSU– Wildlife: Pollinators
• Jeff Hatten / Adrian Gallo – OSU – Soil Nutrients, Carbon/respiration
• Rob Harrison / Marcella Menegale – UW – Nutrient leaching
• Mike Barber / Mohammad Hasan– U. Utah (WSU) – Water issues / Microbial assessment
• Larger LTSP Network
Looking for more…
25
Fall River LTSP
Weyerhaeuser's 15 year oldSoil Productivitystudy in western Washington
Summer 2009
Block 1
Block 2Block 3
Block 4
26
FALL RIVER LTSP - OBJECTIVES
Determine the impact of:
Biomass removalCompaction and tillage Weed control(Fertilization)on stand productivity and soil and nutrient processes in a fertile Pacific Northwest Douglas-fir plantation
27
BIOMASS REMOVAL TREATMENTS
Bole only (BO)Conventional harvest
Total-tree plus all coarse woody debris (TT+)
Total tree
Bole only to 5-cm top
29
COMPACTION +/- TILLAGE TREATMENT
47% of area trafficked during shovel-yardingAerial view
“Non-compacted”Cable-Yarding
“Compacted” Shovel-Yarding
31
FALL RIVER LTSP - CONCLUSIONSAt this productive, nutrient rich site very modest, if any, declines in tree growth were seen in high biomass removal vs standard practices.
Compaction/Disturbance at the level we did had no negative effects on tree growth.
32
GENERAL LTSP - CONCLUSIONSAcross the network of other LTSP sites generally we don’t see large losses in productivity from the experimental removal of residual biomass.
Where fall-down has occurred it was on sites with low nutrient levels prior to harvest so those are potentially the most at risk.
top related