Conservation Effects Assessment Project(CEAP)
Measuring the Environmental Benefits of Conservation
Managing the Agricultural Landscape for Environmental Quality
Why CEAP?
OMB requests for outcome-based reporting
2002 Farm Bill significantly increased conservation funding call from both inside and outside government for better accountability
Assessment is needed to guide development and implementation of future conservation programs
Overview of CEAP
• Watershed case studies (43)• National Assessment
Cropland Wildlife Wetlands Grazing Land
CEAP Highlights…
Blue Ribbon Panel review National Agricultural Library bibliographies
Cropland (set of 5) Wetlands Grazing Lands Wildlife
Literature Syntheses on Practice Effects—What is Known and Not Known
International Workshop on Managing Agricultural Landscapes For Environmental Quality—Strengthening the Science Base (Oct 2006)
Cropland National Assessment-- Goals
1. Estimate the benefits of conservation practices currently present on the landscape
2. Estimate the need for conservation practices and the benefits that could be realized under “full treatment”
3. Simulate alternative options for implementing conservation programs on cropland
Schematic for Construction of the National Assessment
Farm survey data at NRI-CEAP sample points
Field-level modeling APEX
Watershed modeling SWAT
Onsite (field-level) Effects
Off-Site Water Quality Effects
NRI-CEAP Sample
Primary Sample Unit
(PSU)Points
Statistical Design
Activities for Construction of the CEAP Current Condition.
Collect:1. Farm survey (NASS)2. NRI point attribute data 3. Field office records: NRCS/FSA4. Historical weather data
Field-level modeling (APEX)
CEAP Current Condition, onsite
estimates
Select subset of NRI sample points 20,000 cropland
10,000 CRP
Setup data for site specific simulations
Refine APEX model
Soil Data
NASIS
NRI-CEAP Cropland Survey
The survey obtains for each sample point: Three years of crop and cropping practice
information• Crops grown, seeding rates, etc.• Nutrient applications, including manure• Pesticide applications and pest management practices• Field operations, including tillage• Irrigation practices
Conservation practices Conservation Program participation
NASS Farmer Survey• 44 pages • Covers all aspects of
crop production for 3 years.
• Tillage• Fertilizers and
manures• Pesticides• Irrigation• Conservation
NASS Fertilizer
Daily weather—47-year simulation using actual weather for 1960-2006.
Hydrology Erosion Nutrient cycling Carbon cycling Pesticide fate Soil characteristics (temperature, bulk density, etc.) Crop growth Tillage and management operations Field-to-field routing used to simulate field borders,
buffer strips
APEX Model
Root Zone
Shallow (unconfined)
Aquifer
Vadose (unsaturated)
Zone
Confining Layer
Precipitation
Infiltration/plant uptakeSurface Runoff
Lateral Flow
Return FlowPercolation to
shallow aquifer
Hydrologic BalanceEvaporation and
Transpiration
Deep percolation
Modeling Strategy
1. Estimate a CEAP Baseline using farmer survey information at NRI sample points
2. Construct an alternative scenario assuming “no practices”
Difference between these two scenarios represents the benefits of the accumulation of conservation practices currently in place.
Microsimulation Modeling
Thus, the resulting simulation model … Captures the diversity of land use, soils, climate,
and topography as represented by the NRI, and diversity of human behavior as represented in the NRI-CEAP survey.
Estimates the loss of materials at the field scale where the process model performs the best, using site-specific information.
Provides a statistical basis for aggregating results to the national and regional levels.
Soil Type and Management Interactions
Soil Leaching Potential
Management Level Soil Leaching average
Low Moderate Moderately High High
Low 33 28 8 8 21
Moderate 58 31 10 10 30
Moderately High 65 36 12 11 32
High 109 42 17 14 47
Management average 67 34 11 11 33
Non-Cultivated Lands
Channel/Flood PlainProcesses
Point Sources
APEX CultivatedFields
SWAT : Off-Site Effects
EROSION•Water
– USLE– USLE modifications
MUSLE Onstad-FosterRUSLERUSLE 2
•Wind– Manhattan, KS with Bagnolds energy
equation
NUTRIENTS•Nitrogen
–Surface runoffsoluble and adsorbed
– Subsurface flowlateral and vertical
–Mineralization–Immobilization–Denitrification–Volatilization–Nitrification–Crop uptake
•Phosphorus– Surface runoff
soluble and adsorbed– Leaching– Mineralization– Immobilization– Adsorption-desorption– Crop uptake
NUTRIENTS
PESTICIDE FATEGLEAMS
•Surface runoff–soluble and adsorbed
•Leaching
•Degradation–from foliage and soil
•Washoff from plants–rainfall or irrigation
• Management capabilities– Irrigation– Drainage– Furrow diking– Buffer strips– Terracing– Waterways– Fertilization– Manure management– Lagoons
APEX
– Reservoirs– Crop rotation and selection– Pesticide application– Grazing– Tillage
ROUTING COMPONENT•Water
–Overland flow–Channel–Floodplain–Sub-surface
•Sediment–Modified Bagnolds stream power–Deposition – degradation
Overland flowChannelFloodplain
ROUTING COMPONENT
•Nutrients and pesticides
–Soluble materials considered conservative–Adsorbed materials sediment transported –Enrichment ratio concept
SUBAREA FILE• Management• Daily weather• Soil• Channel parameters
– Depth– Width– Length– Slope
• Reservoir parameters– Spillway elevation– Runoff volume– Release rate– Surface area
INPUT DATA• Data Files Residing with Model
– Weather– Tillage– Fertilizer– Soil
– Pesticide– Management– Crop Growth Parameters
RECENT APEX APPLICATIONS
• CEAP – Conservation Effects Assessment Project− National assessment of the effects of conservation
practices on cultivated cropland across the U.S.
Distribution of APEX testing sites across the U.S. that were used in the CEAP sensitivity analysis
