Understory Plant Abundance Is More Important than Species Richness in Explaining Soil Nutrient Variation Following Afforestation on the Eastern Loess Plateau, China

Afforestation plays an important role in controlling soil erosion and nutrient loss on the Loess Plateau China. However, previous studies changes have mainly focused effects of tree species, whereas little is known about how shrubs herbs caused by afforestation drive changes. In this study, we examined variation characteristics understory vegetation nutrients for different types. The results showed that compared to abandoned farmland, plantations significantly increased organic carbon total nitrogen but had no significant effect phosphorus. Robinia pseudoacacia L. forests were more effective than Pinus tabuliformis Carr. increasing content. addition, herbaceous R. forest better explained variation, herb abundance was best explanatory variable; however, shrub contributed P. forest, most. Accordingly, determined plant abundance, rather species richness, may be most factor driving Specifically, regulating biomass litter biomass. By contrast, indirectly affected altering Furthermore, although phylogenetic relationships less composition, they also made contributions. Therefore, should considered addition composition when assessing impact properties future.