MODELING CARBON CHANGES IN AGRICULTURAL SOILS FORESTRY AND AGRICULTURE MODELING FORUM 14 OCT 2004 John Brenner and Joel Brown USDA NRCS
CarbOn Management Evaluation Tool (VRGG-COMET) Calculation tool designed for use with DOE 1605b Voluntary Greenhouse Gas Reduction Reporting System Based on 20 Land Resource Regions with subdivisions Based on Climate, soil and land use data from existing databases Management practices from Rural Carbon Sequestration Appraisal technique Century SOM Model Outputs include uncertainty estimate
CURRENT LAND USE INFORMATION FROM LOCAL KNOWLEDGE (SHEET A) STATE INDIANA COUNTY BLACKFORD FOR INDICATED SOILS ON MAP DETERMINE: MUID (STATSGO ASSOCIATION) IN004 IN005 IN029 IN032 LAND USE INFORMATION TOTAL CROPLAND CLASS I & II CLASS III & IV CLASS V & VI 72.9 90.7 74 83.4 FOREST OR TREES 10.9 0.9 17.5 11.9 GRASS LANDS 14 7.7 8.5 3.1 WATER / WETLANDS 0.1 0.6 0 1.7 URBAN / OTHER 2 0.05 0GENERAL 0 LAND USE INFORMATION FROM LOCAL KNOWLEDGE (SHEET C) TOTAL 99.9% 100.0% 100.0% 100.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% LANDSCAPE DESCRIPTION FLAT ROLLING HILLS STEEP HILLS FLOOD PLAIN STATE INDIANA COUNTY BLACKFORD CARBON SEQUESTRATION RURAL APPRAISAL IS 10% OR MORE OF ANY MUID IRRIGATED (YES/NO): COUNTY LEVEL FARMING AND CROPPING SYSTEM HISTORY FROM PRE 1900 TO PRESENT (SHEET D) IF YES, ANSWER THE FOLLOWING. STATE INDIANA COUNTY BLACKFORD OTHER MUID TIME PERIOD OF % OF SOIL ANNUAL AMOUNT TYPES OF SYSTEMS TOTAL 0.0% 0.0% 0.0% 0.0% 0.0% INSTALLATION TIME FRAME 0.0% 0.0% IRRIGATED 1970-1990+ 0.0% 0.0% APPLIED 0.0% (INCHES) IN004 % ESTIMATE OF COUNTY BEING FARMED DURING THIS TIME FRAME: PRACTICES INSTALLED 85% BY COUNTY AND SOIL TYPE TOTAL CROPLAND: % OF THIS SOIL IDENTIFIED AS CROPLAND. THE SUM OF LAND CAPABILITY CLASS I & II, III & IV, AND V & VI MUST ADD TO THIS %. IN005 CLASS I & II: % OF THIS SOIL THAT IS CLASS I & II CROPLAND. USE IN REPORTING TO DOE FOR CARBON SEQUESTRATION CLASS III & IV: % OF THIS SOIL THAT IS CLASS III & IV CROPLAND. IN029 CROP ROTATIONS (SPECIFY 1 TO 3) (USE SEPARATE SHEET FOR EACH SOIL MUID) CLASS V & VI: % OF THIS SOIL THAT IS CLASS V & VI CROPLAND. 1) CORN-SOYBEAN IN032 STATE INDIANA COUNTY BLACKFORD MUID IN004 FOREST OR TREES: % OF THIS SOIL IDENTIFIED AS FOREST OR TREES. 2) GRASS LANDS: % OF THIS SOIL IDENTIFIED AS GRASS LANDS. ACRES OF CONSERVATION PRACTICES INSTALLED (ACRES) WATER / WETLANDS: % OF THIS SOIL IDENTIFIED AS WETLANDS. 3) COMMON CROP ROTATION (s) GRASS TREE WETLANDS URBAN / OTHER LANDS: % OF THIS SOIL IDENTIFIED AS OTHER LANDS INCLUDING URBAN LANDS, DEVELOPED LANDS, ABANDONED LANDS. CONVERSIONS PLANTING CREATED LANDSCAPE DESCRIPTION: % OF THIS SOIL IN EACH LANDSCAPE DESCRIPTION. AND/OR FOR INDICATED CROPS REDUCED NO-TILL REDUCED NO-TILL RESTORED TILLLAGE TILLLAGE CROP NAME CORN SOYBEAN 1985 YIELD (BU OR TONS/AC) 130 40 1986 N FERT APPLIED (LBS/AC) 110 1987 MANURE APPLIED (TONS/AC) 2 1988 MUID: SOIL MAP UNIT ID FROM STATSGO. (FROM MAP) 1989 TYPICAL TILLAGE OPERATIONS DISK DISK MUID: SOIL MAP UNIT ID FROM STATSGO. (FROM MAP) TIME PERIOD OF INSTALLATION: GIVE THE TIME PERIOD WHEN DRAINAGE PRACTICES 1990 TIME PERIOD OF INSTALLATION: GIVE THE TIME PERIOD WHEN IRRIGATION PRACTICES CULTIVATE WERE INSTALLLED. (i.e. DISK 1930-1950, 1940-1960, 1970- WERE INSTALLLED. (i.e. 1930-1950, 1990, 1940-1960, ETC.) 1970-1990, ETC.) 1991 PLANT PLANT % OF SOIL DRAINED: GIVE AN ESTIMATE % OF SOIL FOR IRRIGATED: THESE SOILS GIVE AN OF ESTIMATE THE AMOUNT FOR THESE OF SOILS DRIANAGE OF THE INSTALLED. AMOUNT OF IRRIGATION INSTALLED. 1992 ANNUAL AMOUNT APPLIED (INCHES): GIVE AN ESTIMATE OF THE ANNUAL AMOUNT CULTIVATE OF IRRIGATION WATER CULTIVATE APPLIED IN INCHES. (6 INCHES, 12 1993 INCHES, 15 INCHES, ETC.) TYPES OF SYSTEMS: TYPICAL TYPE OF IRRIGATION SYSTEM INSTALLED. (CENTER PIVOT, GATED PIPE, ETC.) 1994 1995 Comments: TIME FRAME: PERIOD OF TIME AS SPECIFIED. 1999 % ESTIMATE OF COUNTY BEING FARMED DURING THIS TIME FRAME: GIVE AN ESTIMATE OF THE COUNTY AREA BEING FARMED DURING THIS TIME FRAME. 2000 TYPICAL CROP ROTATION: CROP ROTATIONS INCLUDE (CORN-CORN; CORN-SOYBEAN; CORN-CORN-OATS-MEADOW-MEADOW; CORN-SOYBEAN-CORN-OATS-MEADOW-MEADOW; ETC) MUID: SOIL MAP UNIT ID FROM STATSGO. (FROM MAP) FOR INDICATED CROPS: ACTUAL CROP INFORMATION FOR THE INDICATED CROPS IN THE CROP ROTATIONS. ROTATION: PICK THE TWO MOST COMMON CROP ROTATIONS. IF ONE ROTATION IS >90% OF CROPPED ACRES, CROP: CROP NAME AS SHOWN IN CROP ROTATION. REPORT ONLY THAT ROTATION. TOTAL FOR THE COUNTY SHOULD EQUAL THE CTIC REPORTED VALUES FROM 1989 TO PRESENT. SEE SUPPLEMENTAL INFORMATION. 1996 1997 1998 ANNUAL CONSERVATION PRACTICES INSTALLED YIELD: CROP YIELD IN BU/AC FOR GRAINS OR TONS/AC FOR HAY. REDUCED TILLAGE: REDUCED TILLAGE FARMING WHICH LEAVE GREATER THAN 15% RESIDUE AFTER PLANTING. (INCLUDES N FERT APPLIED: ESTIMATE OF COMMERCIAL NITROGEN FERTILIZER APPLIED ANNUALLY MULCH (LBS/AC). TILL, RIDGE TILL BUT NOT NO-TILL). MANURE APPLIED: ESTIMATE OF MANURE APPLIED ANNUALLY (TONS/AC), BY CROP. NO-TILL: NO-TILL FARMING SYSTEM. TYPICAL TILLAGE OPERATIONS: TYPICAL TILLAGE OPERATIONS USED TO GROW THIS CROP. (EXAMPLES ARE FALL PLOW; GRASS CONVERSIONS: ALL GRASS PLANTING CONSERVATION PRACTICES. SPRING PLOW; CHIESEL PLOW; DISK; HARROW; CULTIVATOR; DRILL; PLANT; ETC.) (WATERWAYS, BUFFERS INCLUDING RIPIARIAN BUFFERS, FILTER STRIPS, TERRACES, CRP). USE 12' WIDTH FOR TERRACES (LF*12/43560=ACRE). USE 40' WIDTH FOR ALL OTHER PRACTICES REPORTED IN LINEAR FEET (LF*40/43560=ACRE). TREE PLANTING: ALL CONSERVATION PRACTICES THAT INCLUDE TREE PLANTINGS. (WINDBREAKS, SHELTERBELTS, AGRO- FORESTRY) WETLANDS CREATED AND/OR RESTORED: ALL CONSERVATION PRACTICES THAT INCLUDE THE CREATION OR RESTORATION OF WETLANDS. Survey Data: Land Use and Management CARBON SEQUESTRATION RURAL APPRAISAL CARBON SEQUESTRATION RURAL APPRAISAL GENERAL LAND USE INFORMATION FROM LOCAL KNOWLEDGE (SHEET B) Modeling Procedure STATE INDIANA COUNTY BLACKFORD CARBON SEQUESTRATION RURAL APPRAISAL HAS ANY PART OF THE COUNTY BEEN DRAINED (YES/NO): IF YES, ANSWER THE FOLLOWING. OPEN DITCH DRAINAGE TILE DRAINAGE MUID TIME PERIOD OF % OF SOIL TIME PERIOD OF % OF SOIL INSTALLATION DRAINED INSTALLATION DRAINED IN004 IN005 IN029 IN032 Simulation Model Results CO 2 Plant Growth Spatial Data: Soils and Climate CO 2 Active SOM Residues CO2 CO 2 Slow SOM CO 2 Passive SOM CO 2 CO 2 90 80 70 60 50 40 30 20 10 0 Griffin Griffin Horseshoe Bend Kentucky Kentucky W. Lafayette S. Charleston Hoyteville Hoyteville Hoyteville Manhattan Wooster Experiments No-tillage Conventional tillage Wooster Wooster Wooster KBS Akron Sidney Uncertainty Estimator
Climate Soils Management Century model Plant Growth Submodel Water Balance Submodel SOM Submodel Residues CO 2 CO 2 CO 2 Active SOM Slow SOM CO 2 Passive SOM CO 2 CO 2
Agricultural Experiments
Methods Use Century to model the management impacts on SOC storage based on field experiments - 60 experiments with over 800 treatments Statistically evaluate differences between the model results and field measurements for SOC storage linear-mixed effect model reflecting uncertainties in model and measurements prediction error for the LRR carbon estimates
Measured vs. Modeled SOC Storage 12000 Measured SOC (g/m 2 ) 10000 8000 6000 4000 2000 0 0 2000 4000 6000 8000 10000 12000 Modeled SOC (g/m 2 )
Refine Uncertainty in Management Impacts Measured SOC Wet Climate Dry Climate Modeled SOC
Quantification of Uncertainty Monte Carlo Approach PDFs for Inputs Carbon Model Empirically-Based Approach [x 1, x 2, x 3,, x n ] Carbon Estimate w/ Confidence Intervals Carbon Model Uncertainty Estimator (based on Model/Experiment Comparisons) Carbon Estimate w/ Confidence Intervals
Management/Environmental Variables of Interest land management systems * tillage practices residue management organic amendments fertilizer management * climate * soil texture potential vegetation * length of practice * *
Are there limits to this Uncertainty Estimator? - Only representative for agricultural systems that are modeled. - Spatial limits