The Sengsengebirge mountains are a folded mountain range in the Upper Austrian Pre-Alps and is part of the Northern Limestone Alps. The heavily karstified mountain range consists mainly of Wetterstein limestone, drains mostly underground and is criss-crossed by several large caves, including the Klarahöhle with a length of over 31 kilometers. The highest elevation is the Hohe Nock at . A large part of the Sengsengebirge has been a nature reserve since 1976 and has been integrated into the Kalkalpen National Park since 1997.
The name can be traced back to the extensive use of its forests in the Middle Ages by scythe forges, of which only a few remain today. The farmers of the region used the manorial forests, which today are mostly managed by the Austrian Federal Forests, for the production of charcoal. Until the 19th century, a large number of mountain pastures were used for mountain farming. The Sengsengebirge was developed for tourism at the beginning of the 20th century and offers a variety of opportunities for hiking, snowshoe and ski tours and some climbing routes.
Geography The Sengsengebirge has a maximum extension between the Steyr in the west and the Krummen Steyrling in the east of 20 km and from north to south of 6 km; it covers a total area of about 75 km².The western border is formed by the upper Steyrtal near Klaus an der Pyhrnbahn and St. Pankraz. South of the confluence of the Hinterer Rettenbach with the Teichl to the Haslersgatter is the Windischgarstner Becken. The Krumme Steyrling to Bodinggraben forms the eastern border and separates the Sengsengebirge from the Reichraminger Hintergebirge. The northern border runs from Bodinggraben via the Ramsau-Molln shooting range to the Steyr. Administratively, the Sengsengebirge is located entirely in the district of Kirchdorf. The municipalities of Molln, Rosenau am Hengstpaß, Roßleithen and St. Pankraz have a share in the Sengsengebirge (in alphabetical order).Pils, Gerhard. "Eine botanische Wanderung auf das Sengsengebirge in Oberösterreich", 1987
Geomorphology
Typical of the Sengsengebirge is the pronounced chain shape caused by the steep stratification. The northern precipices are very steep, rocky and reach wall heights of up to 600 meters. The southern slopes are less exposed and partly interrupted by secondary plateaus. Between Spering in the west and Rohrauer Größtenberg in the east, the mountain range has a ridge-like character, which is only lost from the Rottalsattel, where the mountain range widens into a small plateau. An alpine Karen or Gruben (1300 m - 1500 m) landscape is formed in the broad crest landscape around the Hoher Nock and the Gamsplan (1700 m - 1900 m) and in the Karen or Gruben (1300 m - 1500 m), which descend southwestwards in a bowl shape. Between Rettenbacher Höhe and Koppenalm, the Knödelböden (also Knodelboden) form an elongated Uvala. The lower limit of the karren and doline phenomenon can generally be given as around 1200 m.
Geology Tectonic
Tectonics, the Sengsengebirge is a mighty, northward tilted (north-vergent) anticline of the Staufen-Höllengebirgs-Decke, which belongs to the Tyrolean cover unit (Tyrolian), whereby in the south the Hangendschenkel rises at an angle of between 30 and 40 degrees and gradually turns into a saigere to slightly overturned layer position up to the northern edge of the Sengsengebirgs. Immediately to the north is the boundary to the Reichraminger Decke of the Bajuvarian, which was partially overthrust during the Tyrolean thrust.Gärtner et al.: Atlas der Geologie. Teilblatt 5330.
Lithostratigraphy In its central part, the Höllengebirgsdecke consists almost exclusively of Wetterstein limestone, which was built up from the Anisian to the early Carnian of the Triassic around 247 to 235 million years ago. In contrast to the vertical Wetterstein limestone of the northern edge, where the top layers have flaked off, the lithostratigraphically original sequence of layers can be found at the foot of the mountain in the south. These are the Lunz Formation, Opponitz Formation and Main Dolomite. The main dolomite, which mainly forms the Reichraminger Decke, was deposited during the late Carnian and the Norium around 235 to 208 million years ago.
Former glaciation The Sengsengebirge was partly glacierized during the Ice Ages, whereby the plateau around the Hoher Nock was ice-free and the Neogenee old landscape was preserved. However, glaciers formed on the northern flanks, the nutrient zone of which probably lay beneath the steep northern slopes between Schillereck, Hochsengs and Seehagelmauer and extended eastwards to below the Hoher Nock. It is assumed that during the High Glacial this "Sengsengebirgs glacier" extended in a western section at least as far as the valley floor of Hopfing. Corresponding moraine remains can be found above the ruined Mistleben alpine pasture, at the Feichtau lakes and on the Feichtau plateau. The moraine remains in the Hochkar below the Hoher Nock belong to an eastern section that flowed eastwards into the Blöttenbach valley. A small local glacier may have formed on the south side, which originated under the Schneeberg near the Hoher Nock, flowed in the cirque to the Koppenalm and further on via the Budergrabenkar towards the Rettenbach.
Hydrogeology
The deep karstified Wetterstein limestone drains underground. There are therefore no lakes or streams in the higher areas. The drainage of the Karststock is mainly to the south via the two karst springs of Vorderem Rettenbach (Teufelskirche) with an average filling of 1028 l/s and Hinterem Rettenbach with an average fillingof 1100 l/s. At 1600 at, the Merkensteinbründl on the slope of the Gamsplan is the highest spring outlet in the Sengsengebirge. There are only a few small stillwaters in the Sengsengebirge, including the two Feichtau lakes at 1400 at altitude north below the Seehagelmauer. The smaller lake has neither inflow nor outflow and is classified as a Weiher. The larger of the two Feichtau lakes is fed by a watercourse at 1510 at and is fed by a perennial spring. The water of the two spring branches, which are strong for the altitude, probably comes from the Rauhwacke of the Lunz strata that form the walls here. To the east of the Feichtau lakes lies the Herzerlsee, a moorland lake.
Caves The Wetterstein limestone, which is easy to karstify, offers favorable conditions for cave formation in combination with the remaining interface structure. As of 2019, 77 caves are listed in cadastral group 1651 (Sengsengebirge) of the Austrian Cave Register. Most cave entrances lie between a height of 1300 m to 1600 m They are mostly shaft-like caves, only a few have a pronounced horizontal extension. With a measured length of 31,086 m, the Klarahöhle (Cat.No. 1651/xx) is the longest cave in the Sengsengebirge and the eleventh longest cave in Austria. Below the Rettenbachhöhle (Cat.No. 1651/1), the so-called Teufelsloch, is the source of the Hintere Rettenbach. The ice chapel in the Steyreck (Cat. No. 1651/3) is also well known. With the Kraterschacht (Cat.No. 1651/24), there is also an important ice cave in the Sengsengebirge, whose huge cave ice deposits are the subject of scientific research.Rudolf Weißmair: Eisdatierung und Eisveränderungen im Kraterschacht (1651/24, Sengsengebirge, Oberösterreich) zwischen 1992 und 2009. In: Association of Austrian Speleologists (ed.): Die Höhle, Zeitschrift für Karst- und Höhlenkunde.
Climate
As part of the research activities in the Kalkalpen National Park, around 43 climate stations have been set up since 1993. Some of these are located in the Sengsengebirge, such as the measuring stations on the Kogleralm (south side) and the Feichtaualm (north side). The climate data show a temperature and precipitation distribution typical for the mountains of the Northern Limestone Alps: cool summers with high precipitation and winters with low precipitation. Annual precipitation ranges from 1200 to almost 2100 mm, with precipitation increasing continuously with altitude. Maximum values are reached in the Rohrauer Größtenberg and Hoher Nock areas. In open, higher areas, westerly and north-westerly winds dominate, often accompanied by precipitation. Due to the frequent accumulation of clouds on the northern edge of the Limestone Alps, there is an above-average amount of snowfall for the altitude in the area of the main ridge above the Hopfingboden. On the Feichtaualm (1350 m), the snow cover can last an average of 174 days. are estimated. Snow depths of three meters are not uncommon. The south side often benefits from much better weather in north-facing conditions and also has less precipitation than the north side. The difference in altitude of around 1500 meters results in striking temperature differences between the valley locations and the summit regions of the Sengsengebirge. The average annual temperature at the southern foot is around 8.6 - 10.0 °C, while at the summit of the Hoher Nock the average annual temperature does not exceed 1 °C.
Flora and vegetation
The beech (Fagus sylvatica) accounts for about 30% of the area. It forms extensive areas, especially on the northern slope. The European larch (Larix decidua) characterizes the higher altitudes up to 1500m, where it forms the forest boundary. Depending on the location, there are also white firs (Abies alba), Scots pines (Pinus sylvestris), common ashs (Fraxinus excelsior) and mountain maples (Acer pseudoplatanus).the association of mountain pine (Pinus mugo) dominates the higher altitudes. On the southern slopes, it grows in ditches down to 600m, for example in the Schröcksteingraben. On the other hand, it climbs up to the summit region of the Hoher Nock, leaving only extreme rock and wind zones free. Alpine meadows form on wind-exposed and partially blown-off sites in winter, in which especially the Horst sedge (Carex sempervirens) and the calcareous bluegrass (Sesleria varia) dominate. To the north of the Großer Feichtausee lies a small spruce raised bog. There are two moors in the Mayralm area. The Eisboden is a Fersumpfungsmoor, the Vorderanger is a Verlandungsmoor. The Scheuchzers Wollgras, which is very rare in Upper Austria, grows in the Vorderanger (Eriophorum scheuchzeri) grows in the Vorderanger.
The majority of the endemic plant species of the north-eastern Alps grow in the Sengsen Mountains.
Fauna The Sengsengebirge is rich in game species. Roe deer (Capreolus capreolus), red deer (Cervus elaphus) and chamois (Rupicapra rupicapra) are present in significant populations; mountain hares (Lepus timidus) also live in the area. Of the carnivores (Carnivora), Eurasian lynx (Lynx lynx), stone marten (Martes foina) and pine marten (Martes martes) and red fox (Vulpes vulpes) are present. The brown bear (Ursus arctos) has not been detected since 2004.
Alpine choughs (Pyrrhocorax graculus) and ravens (Corvus corax) are frequently encountered. With Rock ptarmigan (Lagopus muta), Black grouse (Lyrurus tetrix), hazel grouse (Tetrastes bonasia) and capercaillie (Tetrao urogallus), four grouse species are native to the area. The Sengsengebirge is also the distribution area of the golden eagle (Aquila chrysaetos) with two to three breeding pairs. For the Alpine salamander (Salamandra atra), the alpine meadows above the tree line are important. Of the reptile species, adder (Vipera berus) and mountain lizard (Zootoca vivipara) are more widespread. The cave ground beetle Arctaphaenops muellneri, an endemic species of the Sengsen and Reichraminger Hintergebirge, has been found in the Rettenbachhöhle and the Klarahöhle.
History