<div>Runoff erosion response associated with sediment transport as influenced
by erosive energy variability is a highly scale-dependent process. It is
of great significance to effectively identify the spatial scale effect
on erosive runoff energy for understanding the spatial pattern of
sediment flow behavior across various sites. To address this issue,
thresholds for erosive runoff were established based on frequency
analysis and four selected threshold parameters including runoff
duration ( <i>T</i>), stream power ( <i>ω</i>), stream energy factor (
<i>SE</i>) and area-specific sediment yield ( <i>SSY</i>). Based on
these thresholds, 77 erosive events were identified and separated from
non-erosive events for further analysis. The threshold for T was roughly
constant at hillslope but rapidly increased at entire slope. Thresholds
for ω and <i>SE</i> was linearly and positively related to the plot
area. A general increasing trend was observed in the threshold for
<i>SSY</i> from the upper hillslope to the entire slope. The sediment
delivery capacity of erosive runoff varied from 0.075 to 0.115 kg·m·J
<sup>-1</sup>, while the sediment increments capacity of erosive
runoff ranged from 0.43 to 4.47 kg·m <sup>-2</sup>·W
<sup>-1</sup>. The sediment reduction benefit by regulation unit
stream energy factor varied from 5% to 65%. Overall, erosive runoff
events were characterized by longer runoff duration and larger erosive
energy, as well as greater sediment delivery capacity compared to
non-erosive events. Therefore, the runoff regulation on slopes should be
mainly orientated at the erosive energy control and the conversion of
slope runoff from erosivity to non-erosivity.</div>