Agricultural Modeling Team (Phase 7)

AMT Phase 7: Log of Actions and Decisions

• AMT Action and Decision Log [PDF, 311.4 KB]

AMT Phase 7: Foundational Documents

These resources include the Agricultural Modeling Team's charge; initial topics; call for members, list of members, and conflict of interest document for potential members; and workplan as of March 2023.

• Agricultural Modeling Team Phase 7: Charge and Call for Nominations [PDF, 304.1 KB]
• Agricultural Modeling Team Initial Topics 2022 [PDF, 112.6 KB]
• Agricultural Modeling Team Voting Members July 2023 [PDF, 48.2 KB]
• Agricultural Modeling Team Conflict of Interest Disclosure Form [DOCX, 45.8 KB]
• Agricultural Modeling Team Workplan 2023 [PDF, 85.0 KB]

Agricultural Modeling Subcommittee Phase 6

The following information refers to the Agricultural Modeling Subcommittee, which was the precursor to the current Agricultural Modeling Team. Please review the following as reference material describing this group to familiarize yourself with the foundational information that has led us to where we are today.

Agricultural Modeling Subcommittee Phase 6 Scope and Purpose

The Agricultural Modeling Subcommittee provides enhanced agricultural modeling assistance to support the Agriculture Workgroup and the workgroup's Expert Review Panels on technical decisions regarding the development of the Phase 6 modeling tools for the TMDL Mid-Point Assessment in 2017. Functions include:

• Provide agricultural modeling support to the Agriculture Workgroup's Expert Review Panels, coordinate cross-modeling support between the Chesapeake Bay Program Office and USDA agencies, and assist with the development and review of panel recommendations.
• Review current agricultural data inputs to Scenario Builder and the Watershed Model. Consider recommendations for new or improved data sources resulting from the Agriculture Workgroup’s 2013 Modeling Workshop. Make recommendations for data sources to be used post-2017.
• Review current Scenario Builder and Watershed Model assumptions related to the fate and transport of nutrients on agricultural lands. Some specific assumptions that will be studied include: the placement of excess manure on agricultural lands; timing and applications of nutrients; percent of land available for manure application; etc. Make recommendations to the Agriculture Workgroup for new algorithms or process assumptions related to the fate and transport of nutrients on agricultural lands to be used post-2017.
• Coordinate with USDA agencies to identify opportunities to collaborate or integrate with USDA modeling tools and databases for providing sources of agricultural data, alternative modeling structures and analysis methods.

AgWG/AMS Review of Phase 6 Model

This project page is the repository for the Phase 6 model, its documentation, as well as files and links to Tableau pages, specifically as it related to the Agriculture Workgroup (AgWG) and Agricultural Modeling Subcommittee (AMS).

The .pdf "Draft Final Phase 6 Model Review: Comments Received for AMS" was routinely updated and reposted as additional comments were received.

Documentation

All documentation files were uploaded to this FTP site to assist in partnership review of Phase 6: https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/Draft_Phase_6/Documentation/

Documentation of decisions made by the AgWG and AMS pertaining to the Phase 6 modeling tools is available below.

Calibration

A summary PDF of calibration results has been generated and is available for download (large file): https://archive.chesapeakebay.net/Modeling/Phase6/Draft_Phase_6/Watershed_Model/WSM_Outputs/Calibration_Figures/00_Calibration_Figures_All_Phase6Draft.pdf

Other detailed calibration results for each calibrated parameter and river segment can be found in a separate FTP folder: https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/Draft_Phase_6/Watershed_Model/WSM_Outputs/Calibration_Figures/

Further detailed calibrated output for the watesrhed can be found in csv files located at this FTP site: https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/Draft_Phase_6/Watershed_Model/WSM_Outputs/Summary_Loads/

Land use files can be found at this ftp site: https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/Draft_Phase_6/Land_Use/

Watershed Model Inputs

Links to the sites for Watershed Model Inputs can be found at these web pages:

• FAQ regarding Modeling Tools: https://mpa.chesapeakebay.net/Phase6FAQ.html
• Graphical Interface for Phase 6 Model Inputs: https://mpa.chesapeakebay.net/Phase6DataVisualization.html
• CAST Homepage: http://cast.chesapeakebay.net/
• Phase 6 Soil Phosphorus Figures: https://archive.chesapeakebay.net/Modeling/soil-p-history/fig/

Model Review Process

The process by which the partnership could most effectively submit comments and provide feedback to the development of the Phase 6 model was outlined in a document found below. The schedule of webinars was also provided in a document found below.

• Phase 6 Animal Location Template [XLSX, 16.8 KB]
• Phase 6 Approval Process [PDF, 133.3 KB]
• Draft Final Phase 6 Review Comments Received and Draft Responses [PDF, 918.0 KB]
• Agriculture Workgroup and Agricultural Modeling Subcommittee Decisions on Phase 6 Model (2015-2017) [PDF, 478.3 KB]

Phase 6 Scenario Builder Review

Scenario Builder is a data management tool that provides estimates of land use acres, nutrient inputs, cropland attributes, and best management practice (BMP) implementation data to the Chesapeake Bay Program Partnership's Phase 6 Watershed Model. The documentation and initial application rates to crops that are provided in the link below will help inform a full partnership review of the tool's documentation, during which the Agricultural Modeling Subcommittee (AMS) hopes to receive comments that could result in improvements to the tool in the spring and summer of 2016.

June 23, 2016:
The Agriculture Workgroup requested two nutrient spread application procedures be tested in advance of its July 20-21 face-to-face meeting. Nutrient applications from inorganic fertilizer, manure and biosolids from both versions are now available for download at https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/Ph6Calibration_Beta2/20160401/inputs/ScenarioBuilder/. The two procedures are briefly described below.

• The first procedure, known as Beta 3a, relies upon an estimate of fertilizer sales across the watershed, and distributes those sales to counties based upon dollars spent by a county, as reported by the Census of Agriculture, and inorganic crop nutrient need after manure and biosolids applications are made. Using this method, the total pounds of inorganic fertilizer applied across the watershed are equal (never above or below) the total pounds of fertilizer sales estimated across the watershed.
• The second procedure, known as Beta 3b, applies inorganic fertilizer to fulfill crop nutrient need after manure and biosolids applications are made. Using this method, the total pounds of inorganic fertilizer applied across the watershed may exceed or be lower than the estimated fertilizer sales across the watershed. This procedure is similar in method to the current Phase 5.3.2 inorganic fertilizer application procedure.
• States are encouraged to review the results of each procedure prior to the July 20 meeting. A detailed analysis of the two methods, including areas of disagreement between the two methods, will be provided at the meeting.

July 13, 2016:

The purpose of the webinar was to review the inputs to the Beta 3 version of Scenario Builder, review the two methods to representing nutrient spread that were used in Beta 3a and 3b, provide a summary of the results, and to answer any questions that AgWG members and interested parties had when interpreting these results.

Materials from the webinar are available through the following link: https://www.chesapeakebay.net/channel_files/24182/webinar_presentation.pdf

August 23, 2016:

At its July meeting, the Agriculture Workgroup approved the use of AAPFCO fertilizer sales data to inform applications of inorganic fertilizer by county during the calibration period (1984-2013) of the Phase 6 Watershed Model. The Workgroup approved distributing total pounds of inorganic fertilizer sold across the watershed to counties based solely upon inorganic crop application goals left over after applications of biosolids and manure. The files attached below ('Beta 3a1-XXX.xlsx') provide applications and legume fixation by land use and crop following these new recommendations.

Improvements for the April calibration include:

• Inorganic fertilizer was distributed to crops only after all BMPs were simulated that would impact the amount of manure available to crops and the amount of agricultural acres with remaining nutrient application needs.
• Manure mineralization rates, which impact the amount of manure nutrients available to crops, were updated to reflect typical nutrient management mineralization rates by decade.
• Manure recoverability, or the amount of manure generated in a barnyard that can be made available to crops, before and after the implementation of Animal Waste Management Systems was updated to reflect estimates provided in http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs143_012131.pdf
• Acres of barnyards or feeding facilities were updated to reflect the Bay Program’s best estimates per animal type.
• Nutrient application goals for the minor crops, emmer, spelt and triticale, were based upon state-recommended applications on a per acre basis as very little yield data was available to vary the application goals by annual yield.

December 12, 2016:

The Beta 4 Input Data, including nutrients applied by land use and by crop type, are now available to download from the FTP site using the following link: https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/Ph6Calibration_Beta4/Inputs/Scenario_Builder/MattsNutrientsAppliedFiles/

Please use the following link to access a draft version of Scenario Builder documentation and initial application rates to land uses crops for the January, 2016 initial calibration run: https://archive.chesapeakebay.net/?prefix=Modeling/Phase6/

Download the zip file titled: "Ph6CalibrationFiles_20151109.zip"

To access the Scenario Builder draft documentation, download the file: 'SBV6Documentation_01212016.pdf'

• Phase 6 Beta Scenario Builder Webinar Presentation [PDF, 2.4 MB]
• Phase 6 Scenario Builder Documentation [PDF, 1.6 MB]
• Beta3a1 Nitrogen Fixation by Land Use [XLSX, 1.7 MB]
• Beta3a1 Nitrogen Fixation by Crop [XLSX, 10.1 MB]
• Beta3a1 Nutrients Applied to Land Uses [XLSX, 18.5 MB]