Impact of aggregate GMD on soil loss
Only aggregate GMD and crushing energy appeared to increase with
increasing crust crushing energy for the four soil types. The
relationship between aggregate GMD and soil loss for the four soil types
examined in this study is illustrated in Figure 7b. Soil loss appeared
to decrease linearly with increasing aggregate GMD. Actually, soil loss
is directly related to the amount of aggregates >0.84 mm in
diameter, which are considered nonerodible aggregates (Zobeck et al.,
2011). However, the impact of aggregate GMD on soil loss varied among
soil types based on regression coefficients and ANOVA. We found that the
impact of aggregate GMD on soil loss was higher for Farrell sandy loam
and Warden sandy loam than Walla Walla silt loam and Athena silt loam
based on the regression coefficients (Figure 7b).
Aggregate size distribution not only determines the amount of wind
erosion due to the amount of erodible size aggregates present on the
soil surface, but also impacts other key wind erosion factors such as
the threshold friction velocity, PM10 or suspension potential
(Zobeck,1991b). The impact of aggregate crushing energy on wind erosion
will be discussed in section 3.6.