Effect of Pisha sandstone on water infiltration of different soils on the Chinese Loess Plateau

The infiltration of water into soil is one of the most important soil physical properties that affect soil erosion and the eco-environment, especially in the Pisha sandstone area on the Chinese Loess Plateau. We studied the one-dimensional vertical infiltration of water in three experimental soils, created by mixing Pisha sandstone with sandy soil, irrigation-silted soil, and loessial soil, at mass ratios of 1：1, 1：2, 1：3, 1：4, and 1：5. Our objective was to compare water infiltration in the experimental soils and to evaluate the effect of Pisha sandstone on water infiltration. We assessed the effect by measuring soil bulk density（BD）, porosity, cumulative infiltration, infiltration rate and saturated hydraulic conductivity（Ks）. The results showed that Pisha sandstone decreased the infiltration rate and saturated hydraulic conductivity in the three experimental soils. Cumulative infiltration over time was well described by the Philip equation. Sandy soil mixed with the Pisha sandstone at a ratio of 1：3 had the best water-holding capacity. The results provided experimental evidence for the movement of soil water and a technical support for the reconstruction and reclamation of mining soils in the Pisha sandstone area.

Changes of soil quality induced by different vegetation restoration in the collapsing gully erosion areas of southern China

Understanding the influence of collapsing gully management restoration on soil quality and function is essential to the protection of the regional ecological environment in the collapsing gully erosion area.The primary objective of this study was to construct soil quality index(SQI)to assess the influence of different vegetation restoration types on soil quality in collapsing gully restoration.The influence of five vegetation restoration types on soil properties was investigated by using a path analysis,a comprehensive soil quality index(SQI),and a general linear model(GLM).Vegetation restoration was shown to significantly increase the saturated hydraulic conductivity(Ks),mainly due to the effect of the physical parameters of bulk density,soil cohesion,and soil water content.Meanwhile,pH,Ks,soil organic matter(OM),and sand content were revealed as reasonable indicators to evaluate the influence of vegetation restoration on soil quality.Moreover,vegetation restoration was found to significantly improve the soil quality,with the highest SQI value for natural restoration mixed forest(NF),followed by replanted arboreal forest(RA)and replanted scrubland(RS),which were all significantly higher than the SQI value of the erosion area(EA)in the collapsing gully.Additionally,vegetation type explained the most substantial proportion of total variability(46.41%),and restoration time showed a positive correlation with SQI.The results of this study can provide a reference for the restoration and protection of the regional ecological environment in the collapsing gully area.