Summary

SECTION 7.4

AGRICULTURAL LAND PREPARATION

(This page last updated January, 2003)

Emission Inventory Source Category
Miscellaneous Processes / Farming Operations

Method Summary: This category includes 2000 estimates of the airborne soil particulate emissions produced during the preparation of agricultural lands for planting and post-harvest activities. Operations included in this methodology are discing, shaping, chiseling, leveling, and other mechanical operations used to prepare the soil. 

Activity Data Source: County-specific crop acreage is from harvested crop acreage reports for the year 2000, compiled by the California Department of Food and Agriculture from County Agricultural Commissioner reports.  For all regions, information about the operation type, quantity, and the time of year that land preparation operations occur is from agricultural crop calendars, which were developed in consultation with growers and other agricultural experts to accurately reflect current California growing practices. 

Emission Factor Source: In consultation with agricultural experts, twenty crop-specific emission factors were developed and assigned to all crops based on operation-specific emission factors (e.g., discing, chiseling) from field testing conducted by the University of California, Davis. For each crop, the emission factor is the sum of the acre-pass weighted emission factor for each land preparation operation. Emissions are estimated by multiplying crop acrage by the crop-specific emission factor.

Temporal Data: Monthly emissions were calculated based on each crop's monthly crop calendar profile, which reflects the percentage of land preparation activities that occurs in that month. Monthly activity profiles were derived for each county by summing the monthly crop emissions. Land preparation activities are assumed to occur primarily during the day, seven days a week. 

Changes in Method and Emissions Estimate: The emission factor equation reflects new operation-specific and crop-specific emission factors. Crop-specific acreage for each county was updated for 2000 harvested acreage. Temporal profiles were updated to reflect current land preparation activities.  

Date of Last Update: January 2003

Growth Parameter: Growth in this category is based on projections of harvested crop acreage and varies by region. 

Statewide Emissions Summary 
(2000 — Annual Average Tons/Day, Uncontrolled)

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