Soil loss
The total soil loss in Cm, Hr, Vr+Cm, and Hr+Cm was significantly lower
than CK at the maize seedling stage (Figure 5). Vr significantly
augmented the soil loss amount by 7.03- and 2.29-fold at the rainfall
intensities of 50 and 100 mm h-1, respectively.
However, the total soil loss of CK was greater than that of Cm, Hr, and
Vr+Cm, exceeding by 11.87-, 5.99-, and 7.79-fold at 50 mm
h-1 and by 11.10-, 4.37-, 16.18-, and 20.47-fold at
100 mm h-1, respectively. Like the effect on runoff
amount, Hr+Cm also showed the best performance for preventing runoff and
soil loss at 50 mm h-1 (Table 3 and Figure 4). The
total soil loss was not different among the other three conservation
measures of Cm, Hr, and Vr+Cm at 50 mm h-1, although
the ridges of Hr were breached; meanwhile, Cm, Vr, and Hr+Cm showed no
significant difference, but Hr showed a significantly different soil
loss from the three treatments because of ridge rupturing at 100 mm
h-1. The results indicated that the conservation
measures were useful in reducing soil loss; in particular, mulching was
more effective than contour ridging, as seen in the case where the soil
loss caused by Hr increased more than that caused by other conservation
measures, especially under high rainfall intensity conditions, when
contour ridges were destroyed.