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) 720-0127robert.kellogg@usda.gov

Website at: www.nrcs.usda.gov/technical/nri/ceap