National Assessment for CroplandNational Assessment for Cropland
Analytical ApproachAnalytical Approach
Sampling and modeling approach based on a subset of NRI sample points.
Farmer survey conducted to collect needed information at these NRI sample points.
Physical process model (APEX) will be used to estimate field-level benefits.
Off-site water quality benefits obtained by incorporating field-level estimates into a large-scale water quality model (HUMUS/SWAT).
Implementing CEAP Cropland ComponentImplementing CEAP Cropland Component
Initial focus is on water quality, soil quality, and water use conservation.
The most common practices will be addressed first
As the project progresses, the scope will be expanded.
Onsite EffectsOnsite Effects
Reductions in nutrient loss from fieldsReductions in erosion and sediment loss
from fieldsIncreased water use efficiencySoil quality enhancement, including carbon
sequestrationReductions in pesticide loss from farm fields
and environmental risk
Off-Site Water Quality EffectsOff-Site Water Quality Effects
Reductions in in-stream nutrient concentrations. Reductions in in-stream sediment concentrations. Reductions in in-stream pesticide concentrations and
environmental risk. Reductions in the number of days during the year that in-
stream nitrogen concentrations exceed the drinking water standard.
Reductions in the number of days during the warm summer months that in-stream nitrogen and phosphorus concentrations exceed critical thresholds related to algal blooms and eutrophication.
CEAP Sample for 2003CEAP Sample for 2003
The CEAP Sample and Farmer SurveyThe CEAP Sample and Farmer Survey
The CEAP sample is drawn from cropland points in the NRI. Cropped subset: 13,000 useable surveys have
been obtained from 2003-2004 samples. Represents 7% of cultivated cropland NRI points.
CRP subset: 4,000 useable points have been obtained. Represents about 22% of CRP points in the NRI.
CEAP Sample—Cropped PointsCEAP Sample—Cropped Points
For points with crops grown, the survey provides: Three years of crop and cropping practice information
• Crops grown, seeding rates, etc.• Nutrient applications, including manure• Pesticide applications and management practices• Field operations, including tillage• Irrigation practices
Conservation practices Program participation
National Assessment for CroplandNational Assessment for Cropland
Work Plan for the Cropland Component of the
Conservation Effects Assessment Project National Assessment
January 24, 2004
USDA, NRCSUSDA, ARS
Texas Agricultural Exp. Station (TAES)
Modeling StrategyModeling Strategy
Two Overarching Goals:1. Estimate the benefits of the accumulation of
conservation practices currently in place. Construct a “CEAP Baseline” using survey
information. Construct an alternative scenario assuming no
practices. 2. Estimate benefits for practices implemented each
year for comparison to annual program expenditures.
Field-Level Modeling for Construction of the Field-Level Modeling for Construction of the CEAP Baseline and Alternative ScenarioCEAP Baseline and Alternative Scenario
Baseline—simulation of farming activities and conservation practices as reported in the CEAP Survey Database. 42-year simulation using actual weather for 1960-2001 CRP sample points modeled with practice cover
Alternative “no practices” scenario Conservation practices are “turned off” Cropped subset used to simulate cropping possibilities on CRP
points
First set of results will be generated based on 2003-2004 samples and used for Farm Bill assessments.
Schematic for Construction of CEAP BaselineSchematic for Construction of CEAP Baseline
Farm survey and NRIdata at CEAP sample points
Field-level modeling (APEX)
CEAP Baseline, onsite estimates
Watershed modeling (HUMUS/SWAT)
CEAP Baseline, off-site water quality estimates
Modeling StrategyModeling Strategy
Two Overarching Goals:1. Estimate the benefits of the accumulation of
conservation practices currently in place. Construct a “CEAP Baseline” using survey
information. Construct an alternative scenario assuming no
practices. 2. Estimate benefits for practices implemented each
year for comparison to annual program expenditures.
Percent Cultivated Cropland, 1997Percent Cultivated Cropland, 1997
Schematic for Estimating Annual BenefitsSchematic for Estimating Annual Benefits
Subset of CEAP sample points linked to a geographic area
Acres of combinations of practices implemented in a given year and geographic area
Field-level modeling using CEAP sample points
Model results for “with practices” scenario
Model results for “without practices” scenario
Per-acre estimates of conservation practice benefits
Questions? Comments?Questions? Comments?
Robert L. KelloggUSDA-NRCS, Washington, DC(202) [email protected]
Website at: www.nrcs.usda.gov/technical/nri/ceap