Soil Organic Carbon and Moisture Effects of Different Vegetation Restoration Types in the Mu Us Sandy Land

Abstract

[Objective] This study was aimed to explore the characteristics of soil organic carbon and moisture content under different vegetation restoration types and their relationships, and to provide a scientific basis for the selection of vegetation restoration models in the Mu Us sandy land. [Methods] Different vegetation restoration types, including natural restoration of grassland and various plants such as Artemisia desertorum, Salix psammophila, A. desertorum S. psammophila mixed (shrub-shrub mixed), Pinus sylvestris, S. psammophila P. sylvestris mixed (tree-shrub mixed), in the Mu Us sandy land, were studied. Bare sand was used as the control. The effects and correlations of different vegetation restoration types on carbon and water in the 0-5.0 m soil profile were analyzed. [Results] (1) Vegetation restoration increased, with S. psammophila P. sylvestris mixed, P. sylvestris, Grassland, A. desertorum S. psammophila mixed, A. desertorum S. psammophila mixed, and A. desertorum showing decreasing trends, with significant accumulation effects observed within the 0—0.2 m soil depth. As soil depth increased, the organic carbon content of all vegetation types gradually decreased. Within the depth range of 0.8—2.2 cm, A. desertorum, S. psammophila, and A. desertorum S. psammophila mixed exhibited carbon loss. (2) Different vegetation restoration types showed varying degrees of soil moisture deficit in deep soil layers, primarily concentrated at 1—3.0 m soil layer, with S. psammophila P. sylvestris mixed showing the most severe deficit, followed by P. sylvestris, A. desertorum S. psammophila, S. psammophila, Grassland, A. desertorum. (3) Roots were identified as the main factors influencing soil organic carbon content and moisture consumption. Soil organic carbon content exhibited a negative correlation with soil moisture within the 0—5.0 m soil depth range. [Conclusion] Vegetation carbon storage was achieved at the expense of utilizing deep soil moisture, with S. psammophila P. sylvestris mixed exhibiting the lowest water consumption per unit of fixed carbon. The study suggests that S. psammophila P. sylvestris mixed exhibits favorable effects in vegetation restoration from the perspective of soil carbon retention and water retention in the Mu Us sandy land.

Keywords

• vegetation restoration
• soil organic carbon
• soil moisture
• root system
• the mu us sandy land