Objective The diversity characteristics of understory plants in different plantations and their relationship with soil physical and chemical properties were studied to provide theoretical basis for exploring scientific and reasonable ecological restoration mode of sandy land and near-natural vegetation reconstruction.

MethodsIn this study, based on four kinds of plantations (I: Pinus sylvestris plantation ; II: Poplar plantation ; III: Salix psammophila plantation ; IV : Caragana microphylla plantation ), the species diversity of understory herb communities and the physical and chemical properties of surface soil in different plantations were analyzed, and also their relationships were explored.

ResultsThe results showed that the species of understory herbaceous plants in Caragana microphylla plantation were the highest, followed by Pinus sylvestris plantation, Populus plantation, and Salix psammophila plantation. There were many species of Asteraceae, Gramineae and Leguminosae, accounting for 65.39% of the total plant species. There were no significant differences in Shannon-Wiener diversity index, Margalef richness index, Pielou evenness index and Simpson dominance index among the four plantations. However, there were significant differences in soil pH value, organic matter, available phosphorus, hydrolyzable nitrogen and particle composition among different plantations. The soil pH value of Pinus sylvestris plantation was significantly lower than that of the other three plantations. The contents of organic matter and hydrolyzable nitrogen in arbor forest were higher than those in shrub forest, while the content of available phosphorus was higher in shrub forest. There was no significant difference in soil available potassium content among different plantations. There were significant differences in soil pH value, organic matter, available phosphorus, hydrolyzable nitrogen and particle composition among different plantations. The soil pH value of Pinus sylvestris plantation was significantly lower than that of the other three plantations, and the organic matter and water of arbor forest were significantly lower than those of the other three plantations.

Conclusion The composition of understory plants and soil physical and chemical properties of different plantations in the Mu Us Sandy Land are different. Different plantations have no significant effect on the diversity of understory plants. Organic matter, available phosphorus, pH and hydrolytic nitrogen are the main soil factors affecting the diversity of understory plants in plantations.