Transcript PowerPoint

The Development of a Forest
Module for POLYSYS
Burton English,
Daniel De La Torre Ugarte,
Kim Jensen, Jamey Menard
and Don Hodges
USFS Forest Products Laboratory and Southern Research Station
University of Tennessee, Office of Bioenergy Programs - Joint
Meeting
Objectives

Create a forest subsector with
the following characteristics
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Simulates forest supply and
demand market
Allows for land use shifts between
agriculture and forest lands as well
as dedicated energy cellulosic
production sector
Annual time step
Analytical Tool
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POLYSYS:
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305 crop production regions (ASD’s)
National livestock production
National demand market (Elasticity
Driven)
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(Sum of Production = Domestic Supply)
Energy market is goal driven
Solutions compared to a USDA
Baseline
Cropland Base
Private Land Base
938 Million Acres
Total Cropland
434 Million Acres
76 33
33
430.2
34
56
307
395
Cropland
Pasture/range
Woodland
Other
2002 Agricultural Census
POLYSYS Planted Cropland
Cropland Pasture
CRP
Other
POLYSYS Model
Economic Module
POLYSYS
Generated
Solution t-1
ABS
Crop Budgets
Production Year t
POLYSYS
Generated
Lagged Prices
Expected Price
Year t
Regional Supply Elasticities
Responds to changes in
expected price
By ASD
Acres,
Cost of production
Yield
Changes in expected price
Change in Prices Paid
National
Supply
Regional
Production
CP Factors By
ASD for Crop
and Tillage
KLSR Factors By
ASD for Cropland,
CRP, and Pasture
Proportion
Tillage
by ASD and Crop
From Baseline
Based on CTIC
Carbon Seq.
and Emissions by
ASD, Crop, and
Tillage
Change in
Non chemical
Nitrogen
Other Fertilizer
Expenditures
By ASD
Acres,
Cost of production
Year t
Baseline
Acres
Cost of Production
Year t
Imports
Beginning
Inventory
Environmental Module
County Crop Acres
Based on NASS
Change in Acres
Cost of Production
Year t
Change in USLE
Estimated
Erosion by ASD
and HUC
A
Change in
Gross Soil
Erosion,
acres By
ASD and Crop
A
Determine
ASD Change in
Carbon
Sequestration
and Emissions
Change in
Gross Soil Erosion
by ASD
Change in
Sedimentation and
Sedimentation Cost
By 10 USDA
Regions
MOSS
Change in
Carbon
Sequestration and
Carbon Emissions
Extended Economic Baseline

2007 USDA Baseline (2007 to
2016):
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Ethanol use at 12 BGY by 2016.
Crop yield increases for traditional
crops.
No changes in current tillage
practices.
Corn grain was the assumed
feedstock for ethanol production
through the year 2016.
Conversion efficiency for corn
ethanol grows to 3.0 gallons/bushel.
Change in Crop Area from the 8.6
BGY to 18 BGY Scenario 2016
Corn
Cotton
Change in Planted Acres
<0
None
1 - 100,000
Soybeans
> 100,000
Wheat
Environmental Submodule
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Change in Land Use
Change in Input Expenditures
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Change in Soil Erosion
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Fertilizer application changes estimated based
on changes in expenditures in N,P,K (Fert).
Herbicides and insecticides application changes
estimated based on changes in expenditures on
herbicide and insecticides for the 8 major crops.
Estimated using NRCS ASD region KLSR and P
estimates combined with an estimated C factor
(incorporating tillage) based on 1997 NRI data
Changes in land use by POLYSYS region.
Impact on Sedimentation

Made using erosion estimates converted to 99
river basin’s and coupled with sediment delivery
and deposit ratios used in MOSS II along with
Ribaudo’s 1985 cost of erosion study with costs
indexed to 2007.
Environmental Submodule
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Changes in carbon sequestration
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Carbon emissions for each ethanol scenario were
calculated using methods and estimated
coefficients from the carbon lifecycle literature
(West and Marland, 2002, Marland et al., 2003).
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The estimated coefficients and the quantities of
fuel and inputs in the budgets in POLYSYS were
used to calculate total carbon emissions for each
crop in each ASD.
In addition, the carbon sequestered in
agricultural soils for each crop and tillage
practice was estimated using methods outlined
by West et al. (2008).
Herbicide Use: Regional Changes
Changes between 18 BGY and 12 BGY
USDA Baseline Scenarios
Changes between 18 BGY with CRP and
12 BGY USDA Baseline Scenarios
Changes between 18 BGY and 8.6 BGY
Scenarios
Change in Herbicide Expenditures
< -$10,000,000
-$10,000,000 - -$1,000,000
-$1,000,000 - -$1
None
$1 - $1,000,000
$1,000,000 - $10,000,000
> $10,000,000
Erosion: Regional Changes
Changes between 18 BGY and 12 BGY
USDA Baseline Scenarios
Changes between 18 BGY with CRP and
12 BGY USDA Baseline Scenarios
Erosion increases
nearly 4%
when CRP
lands are used
Changes between 18 BGY and 8.6 BGY
Scenarios
Change in Erosion (tons)
< -100,000
-100,000 - -10,000
-10,000 - -1
No Change
1 - 10,000
10,000 - 100,000
> 100,000
Carbon Emissions: Regional Changes
Changes between 18 BGY and 12 BGY
USDA Baseline Scenarios
Changes between 18 BGY with CRP and
12 BGY USDA Baseline Scenarios
Changes between 18 BGY and 8.6
BGY Scenarios
Change in Emissions
(Metric Tonnes - Carbon)
< -25,000
-25,000 - -1
None
1 - 25,000
> 25,000
Carbon Sequestration: Regional Changes
Changes between 18 BGY and 12 BGY
USDA Baseline Scenarios
Changes between 18 BGY and 8.6 BGY
Scenarios
Changes between 18 BGY with CRP and
12 BGY USDA Baseline Scenarios
Change in Soil Carbon
(Metric Tonnes)
< -6,000
-6,000 - -1
None
1 - 6,000
> 6,000
Simulate Forest Supply and Demand
Markets
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Forest Supply Market -- LP
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OBJ maximize Net Present Value
Activities or Decision Variables
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Produce softwood, hardwood saw timber,
pulp, and energy on private industrial and
private non industrial forest lands.
Once land is harvested a decision on whether
it reenters forest land, converts to dedicated
energy, or agricultural sector is determined
using economics and land retention
constraints.
Decision is also made as to whether additional
lands from Ag sector are converted to private
non industrial lands and become forest.
Simulate Forest Supply and Demand
Markets

Forest Supply Market -- LP

Activities or Decision Variables
 Yields for softwood, hardwoods, pulp and
saw timber
 Costs of production based on projected
prices over time
 Land for hardwoods is a mixture of dbh.
 Land for softwoods designated as <5”,
increase by 2”, to > 15” with
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lands harvested < 5” to energy,
Lands between 5” and 9” to pulp wood,
Lands between 9” and 13” to pulp wood or
saw timber, and
Lands > 13” to saw timber.
Simulate Forest Supply and Demand
Markets
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Forest Supply Market – LP
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Constraints
 Volume produced <= Volume demanded
 Volume taken <= Volume available
 Land harvested by site index <= Land
Available by site index
 Land harvested last year = land
transferred to Ag + land planted to
dedicated energy crop + land returned to
< 5” dbh.
 Annual volumes re-estimated based on
growth functions
Simulate Forest Supply and Demand
Markets
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Forest Demand
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Allocated to RHS
Based on national demands and
current logging output
National Demands – Currently
assumed to be RPA driven.
 Regional Allocation – Based on
IMPLAN information generated at the
county level
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Schematic of a Part of the LP
Allow for land use shifts
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Not fully conceptualized
Environmental subcomponents to
Forest Module
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Not being considered at this
time
First one probably should be
carbon
Annual time step