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Originally published Vol.
2, Issue 3 (June 2004)
Conservation Compliance May Reduce Soil Erosion
Roger
Claassen

Between 1982 and 1997, the annual
rate of soil erosion on U.S. cropland declined from
3.1 billion tons to 1.9 billion tons—a reduction
of 1.2 billion tons per year, or about 40 percent.
Of the 1.2-billion-ton drop in annual cropland soil
erosion, 732 million tons occurred on highly erodible
cropland (HEL). During the same period, USDA phased
in a requirement designed to reduce erosion on HEL.
Conservation compliance requires farmers who crop
HEL to apply an approved soil conservation system
or risk losing most agriculture-related Federal
payments, including farm income support. Though
these reductions coincide with the 10-year phase-in
of conservation compliance, not all of the erosion
reduction can be attributed to program requirements.
By breaking down the 732 million
tons of erosion reduction into components, ERS researchers
identified the portion that could be attributed
to conservation compliance. First, about 365 million
tons—roughly 50 percent—of erosion reduction
on HEL cropland occurred on land that was cropped
in 1982 but not in 1997. Because conservation systems
were designed to maintain the viability of crop
production, erosion reduction due to land use change
was not likely to stem from conservation compliance.
Excluding these erosion reductions leaves 367 million
tons.
Second, conservation compliance
requires farmers to eliminate only “excess”
soil erosion—erosion deemed to be damaging
to soil productivity. Typically, excluding the 36
million tons of nonexcess erosion (reduction to
levels less than 5 tons/acre/year) leaves 331 million
tons.
Finally, erosion reduction can
be attributed to compliance only if it occurred
on a farm that receives farm program payments. Thirty-six
million tons are estimated to have occurred on farms
not receiving payments. The remaining 295 million
tons of erosion reduction—25 percent of the
total—are estimated to have occurred in the
context of the conservation compliance requirement.
It is not certain whether these
erosion reductions can be attributed to conservation
compliance. Soil erosion was also reduced on non-HEL,
which is not subject to conservation compliance.
Erosion reductions could also be attributed, at
least in part, to the development of less erosive
farming systems. For example, the development of
machinery that allows planting crops directly into
minimally tilled or untilled fields can reduce both
costs and soil erosion. However, even if these farming
systems would have eventually been adopted by many
farmers, conservation compliance may have prompted
faster and broader adoption.
This
finding is drawn from . . . |
| Environmental
Compliance in U.S. Agricultural Policy: Past
Performance and Future Potential, by Roger
Claassen, Vince Breneman, Shawn Bucholtz,
Andrea Cattaneo, Robert Johansson, and Mitch
Morehart, AER-832, USDA, Economic Research
Service, May 2004. |
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