Effects of moss restoration on soil erosion and soil water content in a temperate vineyard

Abstract. Soil erosion is a serious problem worldwide, as it jeopardizes soil fertility and thus food security. At the same time, agriculture itself is one of the biggest drivers of soil erosion, and vineyards in particular are vulnerable due to often steep slopes, fragile soils, and management practices. Therefore, the search for alternative management practices becomes vital. Since soil erosion is reduced by vegetation cover, this also applies to moss cover. However, research on the restoration and protection of bare soil using mosses as erosion control is still in its infancy. In this study, the restoration of mosses was investigated by applying artificially cultivated moss mats in a temperate vineyard. The effects of moss restoration on surface runoff and sediment discharge were examined compared to bare soil and cover crops using rainfall simulations at three measurement times during one year (April, June, and October). Additionally, soil water content was monitored for each treatment during all rainfall simulations. Mosses initially showed considerable desiccation in summer, whereupon their growth declined. In October, the mosses recovered and re-established themselves in the vineyard, showing a high level of resistance. Moss restoration significantly reduced surface runoff by 71.4 % and sediment discharge by 75.8 % compared to bare soils. While moss restoration had a slightly better effect on reducing runoff and a slightly lower effect on reducing erosion than cover crops (68.1 % and 87.7 %, respectively), these differences were not statistically significant. Sediment discharge varied seasonally for moss restoration, especially from April to June, which is most likely due to the decline in moss cover and the foliage of the vines in June, as concentrated canopy drip points have formed on the leaves and woody surfaces of the vines, increasing erosion. In April and June, the different treatments do not significantly impact soil water content, while in October, bare soil had the highest and moss restoration the lowest soil water content. According to this, the influence of soil cover varies seasonally, with moss restoration not having a detrimental effect on the soil water content in the drier summer months, but retaining the least water in October. Overall, moss restoration proved to be an appropriate and low-maintenance alternative for erosion control, as it requires no mowing and does not reduce near-surface soil water content during summer.