Fig 1.
(A.) Geographic distribution of basin averaged 10Be-derived erosions rate samples (refer to S1 File for data and the list of source publications). (B.) Samples with mean annual precipitation between 0–1050 mm/yr. (C.) Samples with mean annual precipitation between 1050–2200 mm/yr. (D.) Samples with mean annual precipitation >2200 mm/yr.
Fig 2.
Mean basin slope (x-axis) versus log erosion rate (y-axis).
The blue line indicates the linear relationship best fit line between erosion rate and mean basin slope. The grey area around the blue line represents confidence interval.
Table 1.
Variables with their R2 value using erosion rate as response variable.
Fig 3.
Linear regression: Mean annual precipitation (x-axis) versus log erosion rate (y-axis).
Blue line indicates linear relationship best fit line between erosion rate and mean annual precipitation. The grey area around the blue line represents confidence interval.
Fig 4.
Non-linear regression: Mean annual precipitation (x-axis) versus log erosion rate (y-axis).
Blue line indicates the non-linear relationship curve between erosion rate and mean annual precipitation. The grey area around the blue line represents confidence interval. Orange vertical line represents inflection points, where the relationship curve trend changes. Green box on top represents average tree cover percentage in each regime.
Fig 5.
Non-linear regression: Percentage of tree cover (x-axis) versus log erosion rate (y-axis).
Blue curve line indicates non-linear relationship curve between erosion rate and tree cover percentage. Orange vertical line indicates the maxima or threshold value of tree cover percentage.
Fig 6.
Linear regression: Percentage of tree cover (x-axis) versus mean annual precipitation (y-axis).
Table 2.
Statistical models and their R2 value and p value.
Fig 7.
Plots of mean basin slope and precipitation with erosion rate in areas with <11° slope.
A. Mean basin slope (x-axis) versus log erosion rate (y-axis). B. mean annual precipitation (x-axis) versus log erosion rate (y-axis).
Table 3.
R2 value and p-value of erosion rate vs. mean annual precipitation when other variables are constant.
Fig 8.
Comparison of the relationship between erosion rate and mean annual precipitation from different studies.
Black solid curve represents the relationship between precipitation and erosion rate from Wailing and Webb (1983), Brown dashed curve represents the relationship from Langbein and Schumm (1958), yellow solid curve represents relationship from Ohmori (1983), Red solid curve represents the relationship from Wilson (1973), and the blue solid curve represents the curve from this study. Wailing and Webb (1983) and Langbein and Schumm (1958) originally depicted the relationship between sediment yield and precipitation; sediment yield (t km-2yr-1) is converted to m/My using 1 m/My = 2.7 t km-2yr-1.