Summary SECTION 7.4 AGRICULTURAL LAND PREPARATION (This page last updated January, 2003) Emission
Inventory Source Category
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. Growth
Parameter: Growth
in this category is based on projections of harvested crop acreage and varies by region. Statewide
Emissions Summary
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