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Climate change will lead to increased frequencies of weather extremes in Central Europe, such as severe heat waves and droughts, causing high stress intensities for plants. Drought stress also represents a critical factor on many re-cultivated areas with poor edaphic conditions and small soil depths. This includes living wall systems which are applied to cover shotcrete walls and re-integrate them in landscape surroundings. Due to the vertical arrangement of these systems, which limits absorption of rain water, artificial irrigation was considered mandatory, but experimental evidence is lacking. Therefore, we compared soil and plant water relations of test plots on a ‘Green wall’ system with active and deactivated irrigation. During the vegetation period 2017, soil water potential and plant hydraulic parameters (stomatal conductance, relative water content, midday leaf water potential and osmotic potential) of Phleum pratense, the dominating grass on study plots, were measured. In summer 2017, many weeks with humid weather conditions, but also a pronounced heat period were registered. During this period, considerable physiological responses were observed and respective recovery after subsequent days of heavy precipitation. Phleum pratense showed reductions in stomatal conductance (−148.6 ± 118.8 mmolm−2 s−1), relative water content (−9.3 ± 10.1%) and midday leaf water potential (−0.3 ± 0.5 MPa) on the test plot during heat days. Upon precipitation, differences in water relations between plots ceased within few days. Results indicate that integrated irrigation systems are a necessary component of living wall systems.

The establishment of a sustainable vegetation layer on shotcrete walls subjected to road environment represents enormous challenges. High inclination of almost 90°, the exposed position of the walls near streets as well as lack of soil and water supply pose major limiting conditions. The objective of this study was to evaluate the performance of an innovative greening technology for vertical structures in terms of vegetation development on varying plant substrates and geotextiles.The field experiment included testing three plant substrates on basis of nearby rocky excavation material (‘Innsbrucker Quarzphyllit’, ‘Bundnerschiefer’ and ‘Zentralgneis’) combined with compost. Additionally, five geotextiles (geogrid (3x4 mm), geogrid (9x10 mm), coir net, coir mat, geo mat) were applied for assessment. All test combinations were evaluated regarding vegetation cover, species composition, and biomass production from 2015 to 2016. Analyses of chemical properties were conducted for all plant substrates.Results showed highest vegetation cover ratio on ‘Bundnerschiefer’ and ‘Innsbrucker Quarzphyllit’, which can be explained by the favorable mineral composition (nutrient storage capacity) and chemical properties of compost (lower values of electrical conductivity and C/N ratio).In conclusion, the use of ‘Green Walls’ filled with ‘Bundnerschiefer’ or ‘Innsbrucker Quarzphyllit’ plant substrate in combination with netlike geotextiles like geogrid or coir net proved best. They are promising in terms of establishing an optimal vegetation cover on vertical structures and are well suited for integrating shotcrete walls into the landscape. The use of local excavation material for greening purposes thus can be confirmed. Though, the use of high-quality compost is crucial.

The greening of shotcrete walls represents a major challenge due to the extreme environmental conditions for plants and its technical implementation aiming to establish a sustainable vegetation layer. The objective of the study was to assess the performance of an innovative ‘Green Wall’ system (double-layered, integrated irrigation, filled with excavation material, application on vertical inclination) with respect to its microclimatic characteristics. The measurement campaign was conducted from June 2015 to September 2016 in Plon (Steinach am Brenner, Tyrol, Austria). Microclimatic parameters (air temperature, air humidity, short-wave radiation, substrate temperature and wall surface temperature) were investigated by sensors installed in different layers of the greenery system, as well as in a control area (bare concrete wall). Results indicated a pronounced insulation effect of the ‘Green Wall’ system during summer and wintertime. Analyses in July 2015 (30% vegetation cover) and July 2016 (100% vegetation cover) indicated that reductions of temperature fluctuations were predominately attributable to the substrate layers of the greenery system and less to the vegetation cover. Furthermore, reductions of albedo (reflectivity) and heat stress were achieved. In conclusion, the ‘Green Wall’ system is a promising technique with positive effects regarding temperature and radiation as well as human thermal sensation and therefore recommendable for use also in urban areas. In rural areas it helps to optimize landscape aesthetics, as even vertical slopes can be greened.

Soil bioengineering is a discipline dealing with hill slopes, riverbanks, and earth embankment stabilisation, which in recent decades has gained worldwide popularity. Its peculiarity consists in the technical use of vegetation, sometimes coupled with other materials. Owing to aesthetic and environment-friendly characteristics of vegetation, soil bioengineering techniques are frequently adopted to achieve a low environmental impact of protective works within the fields of landscape architecture and environmental restoration. In spite of such success, the origin and the contents of soil bioengineering have not been completely investigated. This paper shows that soil bioengineering is not as old as most of the researchers think; rather, it was developed in a very specific context, the building of highways during the Nazi dictatorship, although it is the result of a longer process. The paper also shows that the contents of soil bioengineering are not related to the mere use of vegetation for stabilisi...

The restoration of steep rock faces with shrubs and trees is difficult due to extreme microclimatic and edaphic conditions. In this study, we tested the applicability of free-standing planted gabions to improve the landscape and achieve protection against rockfall, erosion and enhanced surface flow. Furthermore, we analyzed the effect of preconditioning on drought tolerance of several planted species ( Ligustrum vulgare , Viburnum lantana , Juniperus communis and Pinus sylvestris ). Planted gabions showed sufficient mechanical stability, but survival rates of planted shrubs and trees were reduced by drought stress. Soil water potential on the gabions decreased several times below −1.4 MPa and soil temperature increased up to 30 °C in summer and decreased below −6 °C in winter. The percentage of surviving individuals was correlated with the species’ resistance to drought-induced embolism. Drought tolerance was overall higher in conifer species, while angiosperm species were able to shift their vulnerability thresholds upon preconditioning. We conclude that free-standing planted gabions may be an alternative technique for restoration and securing of critical parts of steep rocky slopes. Preconditioning of plant material used for restoration of drought-prone sites can increase the drought tolerance of some species.

Biomass analyses were conducted to evaluate the growth performance of an Alnus incana (L.) Moench stand established for the restoration of a land slide site. The study aimed to pioneer the quantification of biomass accumulation of alders which were planted for soil bioengineering and stabilisation purposes under extreme soil conditions. For above-ground phytomass estimation, allometric functions on a tree component level were created using linear regression analyses after ln-transformation. Based on D130-D10-relations D10-data were applied for function derivation. Best fits were computed using ln-transformed D10 and height data. At 7,023 stems ha−1 (all trees >20 cm height), the total stand biomass added up to 18,000 kg ha−1, had an LAI of 1.5 and indicated a high productivity even under unfavourable soil conditions. In the light of the results, grey alders appear to be highly valuable for growing on slide prone sites, indicating that they also exert a positive influence on the soil water regime and thus on slope stability.

Schutzmasnahmen vor dem Gebaude sind eigenstandige Bauwerke, die an der Einwirkungsseite des Prozesses unmittelbar vor dem Gebaude errichtet werden. Entscheidend fur die begriffliche Abgrenzung ist — neben der raumlichen Nahe — auch der Wirkungsbezug, somit die unmittelbare Schutzwirkung fur ein einzelnes Gebaude oder eine Gebaudegruppe (Objektschutz). Schutzbauwerke, die in der weiteren Umgebung errichtet werden und eine grosraumige Schutzwirkung ausuben (Schutzwasserbau, Wildbachverbauung, Lawinenanbruchverbauungen), werden in diesem Kapitel nicht behandelt. Informationen dazu fi nden sich beispielsweise in [200], [20] und [226]. Schutzmasnahmen vor dem Gebaude sollen Prozesse aufhalten oder diese ablenken (siehe Tabelle 10.1). Das Ziel ist in allen Fallen, die Einwirkungen aus dem Prozess auf das Gebaude zu minimieren.

Schutzmasnahmen am Gebaude sind physisch mit dem Baukorper verbunden oder direkt in dessen Konstruktion integriert. Vorteilhaft ist, dass die Masnahmen Teil des eigentlichen Bauwerks sind und keine eigenen Schutzkonstruktionen errichtet werden mussen; somit muss auch kein zusatzlicher Grund vor dem Gebaude in Anspruch genommen werden. Der groste Nachteil dieser Masnahmen ist, dass ein direktes Einwirken des Gefahrenprozesses auf das Gebaude in Kauf genommen wird. Folglich besteht in der Regel Sicherheit fur Personen nur innerhalb des Gebaudes, wahrend der Ausenraum um das Gebaude in vollem Umfang (teilweise) gefahrdet bleibt. Die Wirkung der Schutzmasnahmen besteht primar in der ErhOhung der Robustheit des Baukorpers gegen Einwirkung von Naturgefahrenprozessen und in der Dichtung der Gebaudehulle gegen den Eintritt von Wasser, Feststoff en und Schnee.