Soil and vegetation conditions changes following the different sand dune restoration measures on the Zoige Plateau

Restoration of alpine sand dunes has been increasingly attracting the attention of ecologists due to their difficulty and importance among the mountain-river-forest-farmland-lake-grass system (referred as meta-ecosystem) restoration. Alpine sand dunes are suffered from unstable soil and lack of plants. Efficient restoration measures are vital to guide the sand dune restoration. Whether the engineering materials co-applied with seeding could achieve considerable restoration in such areas? Here, sandbag and wicker as environmental friendly materials combined with Elymus nutans seeding were implemented on the Zoige Plateau sand dune, comparing with the control treatment that only seeding. We assessed the topsoil conditions by sampled the surface soil and measured the water capacity and nutrients. We also utilized interspecific relationship and population niche to analyse the plant community structure variances among different restoration measures. Results showed that the soil conditions got clearly improved in sandbag area than that in wicker area when compared with that in control area. The community in control area was the least structured, while the species showed the closest related in sandbag area. In addition, average population niche overlap showed a control (0.26) < wicker (0.32) < sandbag (0.39) ranking. Thus, we suggested that sandbag or wicker co-applied with indigenous grass seeding is a practical and quick restoration approach in alpine sand dunes, and the sandbag may surpasses the wicker. Moreover, soil amending measures including nutrient improvement, and microbial fertilizer addition may further accelerate sand dune restoration.