Decreased Constraints of Wind Erosion on Soil Seed Bank and Vegetation With the Stabilization of Sand Dune in Northern China

Abstract

While various measures have been taken to combat desertification and stabilize sand dunes, the persistence of “far and active sand dune” in northern China remains a great challenge. This study aimed to identify the primary driving factors that contribute to the stabilization of sand dunes within the Horqin Sandy Land. Our research investigated the richness and density of soil seed bank, seedlings, and vegetation communities across different slope positions in both active and stabilized sand dunes. Our results indicated that sand dune stabilization led to a significant increase in soil carbon and nitrogen contents, with increments of 0.09 ± 0.02 and 0.005 ± 0.001 g kg−1, respectively. Compared with active sand dune, the soil clay content and silt content in stabilized dune showed an increased rate of 23.59% and 30.43%, respectively, while the proportion of soil sand decreased significantly. Additionally, variations in the richness and density of seedlings and vegetation were observed across different slope positions, with lower leeward slopes exhibiting the most favorable conditions, hosting 11.4 ± 0.3 species in richness and 142.1 ± 5.4/m2, 303.4 ± 25.9/m2, and 37.2 ± 0.8/m2 in density for soil seed banks, seedlings, and vegetation, respectively. The soil seed bank showed a great potential for the regeneration of pioneer and annual plant species, particularly Agriophyllum squarrosum. Notably, our findings indicated a reduction in the influence of soil wind erosion intensity on the seed bank and vegetation during the stabilization process, as reflected by a 12% reduction in standardized total effects (STE). Conversely, the effects of soil temperature (STE ranging from 0.07 to 0.22), soil moisture (STE of −0.97 in stabilized dunes), and soil nitrogen content (STE of 0.28 in stabilized dunes) became more pronounced. These results underscore the importance of initially deploying mechanical sand barriers to manage active sand dunes, followed by the strategic planting of pioneer species, especially on the leeward slopes, to effectively promote the stabilization of the dunes.