Effects of shrub patch size succession on plant diversity and soil water content in the water-wind erosion crisscross region on the Loess Plateau

• The shrub patch had higher plant diversity and lower richness than the bare land patch.
• The shrub patch could significantly increased species diversity and biomass.
• The soil water was aggregated in shrub patch succession.
• Vegetation pattern was successive and each cycle was benefited by its previous stage

The shrub patch pattern has important influence on the ecosystems in the arid water-wind erosion crisscross regions. The objective of this study was to examine the effects of vegetation pattern of shrub spot patch on species diversity and soil water content at the sand in slopes in water-wind erosion crisscross region on the Loess Plateau. In this study, the shrub patch size was classified to four size classes, contrasting with bare land patch, and herbaceous plants, and soil water content of the shrub patch were measured in each patch. The Shannon–Wiener indices were 0.364 and 1.074 respectively in small and large patches, which were higher than 0.231 in the bare land patch. The Richness index was 1.41 in bare land patch, which was lower than 1.704 in small shrub patch and 4.370 in large shrub patch. The above- and below-ground biomass and surface soil water content were also significantly (p < 0.05) higher in the shrub patch than that in the bare land patch. These results suggest that the shrub patch could significantly increased species diversity, the above- and below-ground biomass, and surface soil water content. Based on these results, the soil was aggregated in shrub patch and the vegetation pattern was successive and each cycle of vegetation pattern was benefited by its previous stage in the water-wind erosion crisscross region on the Loess Plateau.