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Plant roots significantly reduce soil detachment by overland flow. However, there have been few studies on how plant growth time and hydrodynamic characteristics affect the erosion‐reducing potential of plant roots. This study cultivated ryegrass (Lolium perenne L.) and alfalfa (Medicago sativa L.) as representative of plants possessing fibrous roots and taproots, respectively, in silty soil from the Loess Plateau, China. Root‐soil composites were collected monthly from March to September 2021 and subjected to flow scouring in a hydraulic flume at a 15° slope using five different flow discharges (0.05, 0.1, 0.15, 0.2 and 0.3 L s−1). The results of the study indicated that root length density, root surface area density and root mass density exhibited a significant increase during the early growth phase, followed by a slight decrease. All parameters of fibrous roots revealed greater values than those of taproots, except for root mass density. The reduction in soil detachment under varying flow shear stresses showed a significant increase during the early phases of growth, followed by a gradual decline. Notably, fibrous roots demonstrated a greater impact on soil detachment than taproots, and this discrepancy fluctuated over time. Moreover, the contributions of fibrous and taproots to reducing soil detachment decreased from 55.81% to 39.66% and from 38.21% to 20.99% with increasing flow shear stress, respectively. It indicated that the erosion‐reducing potential of plant roots was greater when subjected to low‐flow shear stress compared to high‐flow shear stress. This study can provide a scientific basis for understanding the erosion‐reducing potential of plant roots at different growing stages and under varying hydrodynamic characteristics. [ABSTRACT FROM AUTHOR]

• Natural grasslands improve soil infiltration capacity in both plant and bare patches. • Patchy mosaic patterns make infiltration heterogeneity and redistribute water on slope scale. • Plant with tap root systems produce more effective macropores as preferential flow paths. • Fine roots have a significantly negative effect on the soil infiltration capacity. Soil infiltration capacity is an important factor affecting soil moisture, and is of great significance to plant growth and groundwater recharge in arid and semiarid areas. Patchiness of grasslands widely exist and have a crucial effect on hydrological processes in water-limited regions. This study investigated soil infiltrability under natural grasslands with patchy mosaic patterns based on a series of in-situ tests. Two dominated natural restoration vegetation communities (Bothriochloa ischaemum (B. ischaemum) with fibrous root systems and Artemisia gmelinii (A. gmelinii) with tap root systems) and abandoned land (as control) were selected in the loess hilly and gully region of the Loess Plateau, China. The results showed that natural restoration grasslands significantly improved soil infiltrability in both plant and bare patches, and the emergence of patchy mosaic patterns can result in infiltration heterogeneity to redistribute water on a hillslope scale. Compared to B. ischaemum , A. gmelinii are more likely to facilitate the formation of preferential flow, contributing to the increased soil infiltration rates. The initial, steady and average infiltration rates (IIR , SIR , and AIR , respectively) and soil infiltration capacity index (SIC) were all negatively correlated with both root length density (RLD) and root surface area density (RSAD) of fine roots (diameter < 2 mm) but positively correlated with those of coarse roots (diameter ≥ 2 mm). The main factors influencing the infiltration capacity were the mean weight diameter in the 10−20 cm layer and the RSAD of the fine roots in the 0−20 cm layer, which can explain 98.6 %, 81.7 %, 63.9 %, and 91.3 % of the total variance of IIR , SIR , AIR , and SIC , respectively. This work highlights the important roles of patchy mosaic patterns in affecting soil water redistribution and the stabilization of ecological systems, providing a scientific basis for vegetation selection in the process of vegetation restoration in water-limited regions. [ABSTRACT FROM AUTHOR]

• Soil infiltrability was differentially regulated by soil texture and plant roots. • The variations in regional soil infiltrability were more explained by soil texture. • Various root-soil combinations differentially affected regional soil infiltrability. • Soil texture had the strongest total effect on soil infiltrability on a reginal scale. Soil infiltrability controls precipitation input to soil and plays a crucial role in regulating soil eco-hydrological processes and ecosystem production in water-limited areas worldwide. The effects of root traits on soil infiltrability have been widely investigated at individual sites, but root-soil interactions and their effects on soil water infiltration over large spatial scales remain poorly understood. This study aimed to identify the unique characteristics of soil infiltration processes and different contributions of soil texture and root morphological traits to soil infiltrability. For this purpose, 153 plots of natural revegetated land with two contrasting plant species (Artemisia gmelinii Web. with tap root systems and Stipa bungeana Trin. with fibrous root systems) and bare land were selected in three regions along a texture gradient in the Loess Plateau of China. The results showed a distinct spatial variability of soil infiltration rates across the three regions with soil texture explaining the variability more strongly than plant species at several infiltration stages. Rooted soils had higher infiltration rates than bare soils, with nonsignificant inter-species difference under three soil texture types. Furthermore, soil texture and root morphological traits explained 92.03% and 74.75% of the total variance of soil properties (soil organic matter, aggregate stability, and soil porosity), and their interaction effects (73.09%), accounted for a considerable proportion. These findings suggest that soil texture and root morphological traits indirectly affect soil infiltrability by modulating soil properties, with soil texture having a higher contribution. In addition, the effects of root morphological traits on soil infiltrability were found to be dependent of soil texture on the regional scale. Therefore, the effects of soil texture and root-soil interaction deserves further attention in assessing soil hydrological processes on large spatial scales in the future. [ABSTRACT FROM AUTHOR]

• The pathways of roots affecting soil electric field are analysed. • Different root parameters for predicting soil electric field are compared. • Effect of soil electric field on soil aggregate stability is elucidated. • Effect of soil electric field on rill erodibility is quantified. Soil electric field (E 0) might have strong effects on rill erosion, and it is in turn largely affected by root growth. This study aimed to quantify the ability of roots to predict E 0 and elucidate the effects of E 0 on the mean weighted diameter of soil aggregates (MWD) and rill erodibility (K r). Samples were collected from three typical areas in the Loess Plateau of China, and each area had two typical grasslands. Soil detachment rates were measured using a hydraulic flume under five discharges (0.1, 0.2, 0.3, 0.4, and 0.6 L s−1) on a slope of 15°. The results indicated that plant roots negatively contributed to E 0. The mean E 0 of grasslands (rooted soil) was lower by 3.27 times compared with that of fallow lands (root-free soil). With significant correlation (P < 0.05), root length density (RLD) and root surface area density (RSAD) were found to be suitable parameters for predicting E 0 , which decreased exponentially with RLD (R2 = 0.306) and RSAD (R2 = 0.381). In addition, E 0 strongly affected MWD and K r by influencing soil repulsive forces. E 0 was negatively correlated to MWD (logarithmic function, R2 = 0.96), but positively correlated to K r (linear function, R2 = 0.88). Our results provide new insight into the mechanism of rill erosion considering plant roots. [ABSTRACT FROM AUTHOR]

• Artificial forests had better soil C and N sequestrations than restored grasslands. • Artificial forests and grassland had a similar ability to improve soil aggregates. • N-fixing species played a crucial role in affecting on soil C and N sequestrations. Vegetation restoration is an important factor affecting soil carbon (C) and nitrogen (N) sequestration. However, the effects of the type of vegetation restoration on soil C and N sequestration varies owing to different environmental conditions. Therefore, additional studies should explore the effects of vegetation restoration type on soil C and N sequestration, especially between natural restoration and artificial afforestation. This study explored the differences in improving soil C and N sequestration between artificial forests (AF) and natural grasslands (NG) that had been converted from sloping cropland over 20 years since the implementation of GGP (Grain for Green Program) on the Central Loess Plateau, China. The results showed that NG and AF significantly increased the 0–20 cm soil organic carbon (SOC) content but had a minimal impact on the 20–100 cm SOC content after 20 years of vegetation restoration. In addition, the two vegetation restoration types significantly increased the 0–60 cm soil total nitrogen (STN) content, but they both had no significant effects on the 60–100 cm soil layer. Moreover, the C and N sequestration capacities of AF were higher than those of NG due to the AF had higher plant biomass and lower plant biomass C:N ratios compared to NG. The AF and NG both significantly increased the soil aggregate structure and stability following cropland conversions. Apart from soil aggregates playing a crucial role in affecting soil C and N sequestration, plant biomass and its C:N ratios also had the most substantial effects. The results suggested that soil aggregate stability and the quantity and quality of input organic matter have strongly influenced soil C and N sequestration post-restoration; moreover, N fixing species is more conducive to soil C and N sequestration and the artificial forests had higher C and N sequestration capacities than natural grasslands in the Loess Plateau, with a mean annual precipitation of 505 mm. [ABSTRACT FROM AUTHOR]