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An improved understanding of the potential controls on vegetation carbon sequestration (VCS) is essential for the prediction of VCS in response to global change. Ecosystem restoration can provide remarkable contributions to VCS. However, attention to the impact of soil conservation (SC) on VCS is lacking. Therefore, the Yellow River Basin, a typical area of soil erosion in the world, was chosen as the study area. The VCS and SC trends from 2000 to 2020 were analyzed and the potential response of VCS to SC was explored by adopting correlation analysis, elastic coefficient method, geographically weighted regression model, and geographical detector model. The influence of SC drivers on the spatial heterogeneity of VCS was also revealed. Results showed the following: (1) VCS and SC had a significant upward trend, especially in the eastern monsoonal ecoregion. (2) The area with a significant positive correlation between VCS and SC accounted for 31.74% of the total, mainly concentrated in the key areas of SC, wherein a 100% increase in SC would lead to a 25%–100% increase in VCS. (3) Among the SC drivers, vegetation cover and management (C) factor and rainfall erosion force (R) factor mainly influenced spatial heterogeneity in VCS, and their interaction considerably enhances this effect. Therefore, the interaction between precipitation and vegetation should be considered when evaluating the impact of water erosion management on VCS. The results of the study have important implications for the enhancement of VCS capacity of degraded land in the ecological restoration process. [ABSTRACT FROM AUTHOR]

The spatial distribution pattern of vegetation is of great significance to the prevention and control of soil erosion in spoil tips. The objective of this study was to evaluate the effects of spatial distributions of grass strips on soil erosion in spoil tips. A field runoff plot (20 m long, 1 m wide, and 0.5 m deep) was used for inflow simulation experiments under four inflow rate patterns (even, rising, falling, and rising–falling) and five grass strip patterns (patterns I–V). Results showed that the runoff reduction benefit (RRB) and soil loss reduction benefit (SLRB) of grass strip patterns were 12.23–49.62% and 12.92–80.54%, respectively. The optimal grass strip pattern was when the grass strips were distributed on a slope in bands (pattern V). In this pattern, the soil and water conservation effects were best, with RRB and SLRB of 43.87% and 58.09%, respectively. The grass strip patterns exhibited a significant time-limited effect on controlling soil erosion. The maximum amount of soil loss reduction for patterns II, III, IV, and V was 93.02, 84.30, 65.86, and 98.26 kg, respectively. Soil loss reduction caused by decreasing runoff (SRR) for grass strip patterns was the main factor controlling erosion. The efficiency coefficient of soil loss reduction caused by decreasing runoff for pattern V was higher than that for the other patterns. The grass strip pattern V (i.e., grass strips were distributed on a slope in bands) should be considered a priority in the prevention of soil erosion in spoil tips. This study can guide the configuration of vegetation control measures for soil and water loss in spoil tips. [ABSTRACT FROM AUTHOR]

• Quantified the effect of the slope, inflow rate and scouring times on soil loss of spoil tips. • Rill depth was the best rill morphological parameter for evaluating rill erosion of spoil tips. • Shear stress was the best hydrodynamic parameter for predicting rill erosion of spoil tips. The soil erosion of spoil tips seriously threatens the safety of people's lives and property and the surrounding ecological environment. Rill erosion is an important cause of water and soil loss in spoil tips. This study investigated the rill erosion on spoil tip slopes, the morphological changes of rills and the mechanisms of rill erosion. A field runoff plot (5 m long, 1 m wide and 0.5 m deep) with three inflow rates (1.6, 2 and 2.4 mm min−1) and three typical slopes (28°, 32° and 36°) was used for runoff simulation experiments. Results showed that inflow rate was the most important factor affecting soil erosion, which contributed 68.87% and 60.54% to the runoff rate and soil loss rate, respectively. Rill development has three stages: formation, development and adjustment. The overall predominance of parallel-shaped rills suggested that rill formation was dominated by concentrated runoff. Inflow rate exerted the greatest effect on the average rill width and average rill depth, with contribution rates of 73.11% and 60.26%, respectively. Meanwhile, slope exerted the greatest effect on the rill width-to-depth ratio, with a contribution of 60.45%. The average rill depth was the best indicator of rill morphology for evaluating rill erosion. Reynolds number was the best hydraulic parameter for predicting rill erosion. Flow shear stress was the best hydrodynamic parameter to describe rill erosion mechanism, with a critical value of 1.98 Pa. These results contributed to elucidating the rill erosion mechanism of spoil tip slope and provided a scientific basis for its soil erosion control. [ABSTRACT FROM AUTHOR]