Map Description:
This dot density map shows acres where
excessive erosion from wind and water is
occurring on cropland. Red dots represent
5,000 acres of highly erodible land eroding
excessively (60.4 million acres). Yellow
dots represent 5,000 acres of non-highly
erodible land eroding excessively (51.6
million acres). Data are aggregated by
8-digit hydrologic units. Excessive erosion is
defined as erosion greater than the tolerable
rate (T). The Universal Soil Loss Equation
(USLE) is used to calculate water erosion.
The Wind Erosion Equation (WEQ) is used
to calculate wind erosion. A total of 112
million acres are eroding excessively
resulting in 1.3 billion tons of erosion. Areas
with 95% or more federal lands are shaded
gray. Excess erosion leads to water quality
concerns from sediments, nutrients, and
pesticides as well as air quality in wind
erosion areas of the West, Midwest,
Northern Plains, and Southern Plains. Excess
erosion is also an indicator of forgone
opportunities for improving soil, water, and
air quality, sequestering carbon dioxide, and
helping in goals to reduce greenhouse gases
in the atmosphere.
Cautions for this Product:
Erosion by water includes sheet and rill erosion and
excludes gully erosion. Within an 8-digit hydrologic
unit, dot counts represent acreage totals correctly
plus or minus one dot to account for remainders.
This map does not show rates of erosion or how
much erosion has occurred. Data are not collected
on Federal land. Data are not available for Puerto
Rico, Alaska, and the Pacific Basin.
For Further Information:
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