Full Method (121Kb)


Farm field activities produce many different pollutants. The amount of a particular pollutant emitted varies during the year along with the level of activity. Other factors, such as weather, also contribute to seasonal variations in emission levels; however, this method only describes the development of activity-based profiles.

The final outputs from this method are normalized monthly profiles (which sum to 1.0 for the year) for the following: Land preparation activities for all crops; planting activities for all crops; cultivation activities for all crops; harvesting for cotton and nuts; all activities for all crops. The land preparation profiles are used in Section 7.4 of the stationary source emissions inventory methodology as the profiles for agricultural tilling. Section 7.4 only includes land preparation activities such as postharvest and preplanting earth manipulation, including: Disking, plowing, chiseling, floating, land planing, subsoiling, etc.; to break up, turn over, level, shape, etc. The harvesting profiles are used in Section 7.5 of the stationary source emissions inventory methodology. The all-activity profiles are used in the heavy-duty farm equipment exhaust emissions inventory. The all-activities profiles include land preparation, planting, cultivation, and harvesting operations. This methodology revision consolidates the calculation of all of the agricultural activity-related temporal profile estimation methods into one overall methodology.

The all-activities and land preparation profiles included with the previous Section 8.10 (1994) for heavy-duty farm equipment and Section 7.4 (1990) for agricultural tilling, respectively, were statewide estimations of monthly activity levels. The profiles for the latest revisions of these sections (both revised in 1997), as well as the new harvesting emission calculation method (Section 7.5, created in 1997), and the planting and cultivation profiles (included in anticipation of methods being developed for planting and cultivation), are now calculated based on individual crops for individual counties. All-crop weighted average profiles are then produced for each county, and these are used for the agricultural tilling and heavy-duty farm equipment emission categories; combined cotton and nut weighted average profiles are produced for each county and used for the harvesting emission category.

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This page last revised on November 12, 1997
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