Grassland Restoration at a Graded Ski Slope: Effects of Propagation Material and Fertilisation on Plant Cover and Vegetation

Abstract

The increasing anthropisation of mountain regions is a cause of soil degradation, which needs to be addressed. Conventional methods of ski slope revegetation often fail to stabilise the soil and recover natural vegetation. To test alternative methods to create a persistent, biodiversity-friendly plant cover, different sowing (site-adapted native propagation materials vs. forage cultivars vs. no sowing) and fertilisation treatments were compared over nine years at a graded ski slope. Because of the gravelly soil, the ninth-year plant cover was only 65%, which was sufficient to prevent erosion. All native propagation materials were equally efficient at recreating a semi-natural grassland. Except for Festuca rubra, the forage cultivars did not persist. However, native volunteer species from close natural ecosystems efficiently colonised plots sown with forage cultivars and plots that were not sown. This resulted in a lower plant cover but a high similarity to the surrounding vegetation. Fertilisation had a positive but transient effect on plant cover and a little negative effect on species richness. High-altitude sites with gravelly soils should be revegetated with native propagation materials. Using forage cultivars can attain a persistent plant cover only if the sown non-persistent cultivars are replaced by the species arriving from nearby surrounding vegetation.

Microbial Fertilizers and Shading Contribute to the Vegetation Assembly and Restoration of Steep-Slope after Soil Spray-Sowing in the Yuanjiang Dry-Hot Valley Region

“…Our results indicate that soil spray-seeding not only improves species richness and abundance, but also accelerates seedling growth when compared with artificial seeding and arch columns + planting bags in the Yuanjiang dry-hot valley region, which aligns with studies suggesting that soil spray-seeding is the superior method for vegetation restoration of expressway slopes in semi-humid areas [25,26], and that soil spray-seeding provides a good soil substrate for plant growth and community assembly combining shrubs, flowers, and grass [39][40][41]. Shang et al [42] indicated that natural recovery is a simple and cheap way to increase grass coverage in sub-humid and humid areas, but that was unsuccessful for slope recovery in the dry-hot valley region, probably because (1) seeds on soil surfaces are more vulnerable to animal feeding and sun exposure; (2) steep slopes tend to cause seed loss and soil erosion during the rainy season; (3) climate conditions in the dry-hot valley inhibited the germination and growth of many species; (4) the degraded land lacked seed banks for woody tree species [43][44][45]. Although arch columns + planting bags have produced good results for the restoration of slopes along highways and railway in certain areas [46], they are expensive and unsuitable in the dry-hot valley area.…”

Nitrogen fertilizer enhances vegetation establishment of a high‐altitude machine‐graded ski slope

“…While several scientific studies dealing with European Alps was published until the 1990s, a few papers can be found in recent issues (e.g. Hudek et al 2020; Scotton 2021).…”