The influence of recultivation technique and seed mixture on erosion stability after restoration in mountain environment

Abstract

Control of erosion, and all of its after effects, from increased surface drainage and erosion to the formation of karst, is one of the essential problems when undertaking recultivation following necessary interventions in the sub-alpine and alpine vegetation stage (high zones). Average slope inclinations of 30-45% in the vicinity of ski runs, and far above in areas of natural erosion and avalanche zones, make restoration processes with sufficient erosion protection the prerequisite for success. Only a sufficient vegetation development of more than 70% ground cover stabilises the topsoil in the long term and reduces soil erosion to an acceptable degree. From 1999 to 2002, an international EU project with the participation Centre Raumberg-Gumpenstein (AREC) on five different Alpine sites at altitudes from 1,245 to 2,350 m above sea level. The aim of the work was the formulation of practicerelevant requirements for recultivation following intervention in high zones, especially following constructional measures in the vicinity of ski runs and lifts, torrent-and avalanche barriers. In a statistical comparison, the relationship between restoration techniques, seed mixtures of differing ecological value and vegetation cover was observed. The influence of application technique on erosion processes after restoration was obvious for the first two vegetation periods. Only with the additional use of mulch covers could increase surface drainage and noticeable soil loss be avoided. At high altitudes, the choice of seed mixture, irrespective of whether rapid or slow growing and independent of the extent of accompanying fertilisation, had no significance in the first two vegetation periods following sowing. In the following growing seasons, however, higher cover values were obtained with site-specific seed mixtures at three of the five experimental sites. While few species of the commercial seed mixture showed satisfactory persistency, most of the grasses and in particular the alpine leguminosae of site-specific seed mixtures increased their share during the observation period. In the long-term, sufficient protection against erosion is only guaranteed by the use of stable, enduring and ecologically adapted species.

Quality and germination capacity of seed material harvested from an Arrhenatherion meadow

“…In general, it is desirable to mix an early and a late harvest to provide the greatest possible spectrum of species. A harvesting date set either too early or too late can lead to the disappearance of several species (Kirmer and Tischew, ; Krautzer et al ., ; Scotton et al ., ). Species number and the composition of the harvested material are strongly dependent on the type of meadow (Kiehl et al ., ).…”

Designing seed mixtures for restoration on alpine soils: who should your neighbours be?

“…) using methods like seeding, fertilization, turf transplants and mulching (Krautzer et al. ; Vega et al. ).…”

“…This is a cheap and simple approach (Krautzer et al. ), but in recent years there has been increased emphasis on using seed mixtures of local origin (vander Mijnsbrugge et al. ; Krautzer et al.…”

Soil Erosion and Surface Runoff on Slopes in Mountain Environment Depending on Application Technique and Seed Mixture – A Case-Study

“…higher vegetation cover and thus better protection against erosion three years after sowing, no need for further fertilisation and maintenance on most sites and a much higher percentage of sustainable species are only some of the essential advantages (Krautzer et al 2010). However, the most risky period where erosion processes can cause considerable damage are the weeks after sowing.…”