The Development of a Forest Module for POLYSYSBurton English, Daniel De La Torre Ugarte, Kim Jensen, Jamey Menard and Don HodgesUSFS Forest Products Laboratory and Southern Research StationUniversity of Tennessee, Office of Bioenergy Programs - Joint Meeting

ObjectivesCreate a forest subsector with the following characteristicsSimulates forest supply and demand marketAllows for land use shifts between agriculture and forest lands as well as dedicated energy cellulosic production sectorAnnual time step

Analytical ToolPOLYSYS:305 crop production regions (ASDs)National livestock productionNational demand market (Elasticity Driven)(Sum of Production = Domestic Supply)Energy market is goal drivenSolutions compared to a USDA Baseline

Cropland Base2002 Agricultural Census

POLYSYS ModelEconomic ModuleEnvironmental Module

Production Year tRegional Supply Elasticities Responds to changes in expected price

POLYSYS GeneratedLagged Prices

Expected PriceYear t

ABSCrop Budgets

POLYSYSGeneratedSolution t-1

YieldChanges in expected priceChange in Prices Paid

Beginning Inventory

Regional Production

Imports

National Supply

By ASDAcres, Cost of production

By ASDAcres, Cost of productionYear t

Baseline AcresCost of ProductionYear t

Change in AcresCost of ProductionYear t

Change inNon chemicalNitrogenOther FertilizerExpenditures

Change in Gross Soil Erosion, acres By ASD and Crop

Proportion Tillage by ASD and CropFrom BaselineBased on CTIC

County Crop Acres Based on NASS

KLSR Factors By ASD for Cropland, CRP, and Pasture

CP Factors By ASD for Crop and Tillage

Change in USLE Estimated Erosion by ASD and HUC

DetermineASD Change in Carbon Sequestration and Emissions

Carbon Seq. and Emissions byASD, Crop, and Tillage

Change inCarbon Sequestration andCarbon Emissions

A

A

MOSS

Change inSedimentation andSedimentation CostBy 10 USDA Regions

Change inGross Soil Erosion by ASD

Extended Economic Baseline2007 USDA Baseline (2007 to 2016):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 2016CornSoybeansWheatCotton

Environmental SubmoduleChange in Land UseChange in Input ExpendituresFertilizer 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.Change in Soil ErosionEstimated using NRCS ASD region KLSR and P estimates combined with an estimated C factor (incorporating tillage) based on 1997 NRI dataChanges in land use by POLYSYS region.Impact on Sedimentation Made using erosion estimates converted to 99 river basins and coupled with sediment delivery and deposit ratios used in MOSS II along with Ribaudos 1985 cost of erosion study with costs indexed to 2007.

Environmental SubmoduleChanges in carbon sequestrationCarbon 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). 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 ScenariosChanges between 18 BGY and 8.6 BGY ScenariosChanges between 18 BGY with CRP and 12 BGY USDA Baseline Scenarios

Erosion: Regional Changes

Changes between 18 BGY and 12 BGY USDA Baseline ScenariosChanges between 18 BGY and 8.6 BGY ScenariosChanges between 18 BGY with CRP and 12 BGY USDA Baseline ScenariosErosion increases nearly 4% when CRP lands are used

Carbon Emissions: Regional ChangesChanges between 18 BGY and 12 BGY USDA Baseline ScenariosChanges between 18 BGY and 8.6 BGY ScenariosChanges between 18 BGY with CRP and 12 BGY USDA Baseline Scenarios

Carbon Sequestration: Regional Changes

Changes between 18 BGY and 12 BGY USDA Baseline ScenariosChanges between 18 BGY and 8.6 BGY ScenariosChanges between 18 BGY with CRP and 12 BGY USDA Baseline Scenarios

Simulate Forest Supply and Demand MarketsForest Supply Market -- LPOBJ maximize Net Present ValueActivities or Decision VariablesProduce 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 MarketsForest Supply Market -- LPActivities or Decision VariablesYields for softwood, hardwoods, pulp and saw timberCosts of production based on projected prices over timeLand for hardwoods is a mixture of dbh.Land for softwoods designated as 15 with lands harvested < 5 to energy,Lands between 5 and 9 to pulp wood,Lands between 9 and 13 to pulp wood or saw timber, andLands > 13 to saw timber.

Simulate Forest Supply and Demand MarketsForest Supply Market LPConstraintsVolume produced

Simulate Forest Supply and Demand MarketsForest DemandAllocated to RHS Based on national demands and current logging outputNational Demands Currently assumed to be RPA driven.Regional Allocation Based on IMPLAN information generated at the county level

Schematic of a Part of the LP

Allow for land use shiftsNot fully conceptualized

Environmental subcomponents to Forest ModuleNot being considered at this timeFirst one probably should be carbon

Annual time step

POLYSYS contains the entire cropland base with 34 million acres removed for use in minor crops and farmsteads, etc. In the