In order to clarify the influence of gravel content on runoff and sediment yield characteristics of lime-soil engineering deposit slope in Karst area

the runoff characteristics and erosion characteristics of lime-soil slope with meta-soil (30%) and meta-gravel (70%) under incremental rainfall (0.5

1.0

2.0

2.5 and 3.0 mm/min) were studied by indoor simulated rainfall test method. The results showed that: (1) With the increasing of rainfall intensity

the runoff rate of each slope showed a stable growth fluctuation trend

and the runoff rate of soil slope was less than that of two kinds of gravel slope

and the runoff yield of partial soil and partial stone slope was 0.49 times and 0.37 times higher than that of soil slope. (2) Under the rainfall intensity of 1.0~3.0 mm/min

runoff rate of each slope fluctuated in the range of 0.16~5.4 g/(m2·s)

which showed a trend of steady-fluctuation increase. The change range of erosion rate of partial soil slope and partial stone slope was 0.16~5.4 g/(m2·s) and 0.06~0.74 g/(m2·s)

respectively. The former had a large range of variation and strong fluctuation

while the latter had a small and stable range. With the increasing of gravel content

the erosion amount of each slope increased first and then decreased. The erosion amount of partial soil slope was 2.5 times higher than that of soil slope

while the erosion rate of partial stone slope was 0.9 times lower than that of soil slope.(3) The erosion rate of soil

partial soil and partial stone slope was positively correlated with the runoff rate

which was power function

linear function and linear function

respectively. The results could provide a scientific basis for soil and water control of abandoned slag field in Karst area of Northwest Guangxi.