A new species in the Simulium vernum group from the Northern Limestone Alps of Austria: Simulium hasekei (Diptera: Simuliidae)

Simulium hasekei new species is described from the Alps of Austria. It is characterized by a broad trapezoidal ventral plate in the male, long straight arms of the genital fork in the female, a well-developed anterodorsal projection on the weakly woven cocoon, and a deep rounded postgenal cleft and strong paralateral hypostomal teeth in the larva. The species is chromosomally most similar to the Holarctic S. bicorne Dorogostaisky, Rubtsov & Vlasenko and S. fontinale Radzivilovskaya and the Nearctic S. craigi Adler & Currie. It is known from one small ponor brook, in association with S. aureum (Fries) s. s., S. beltukovae (Rubtsov), and Simulium vernum Macquart s. s.

Log Transport in the Limestone Alps, Austria: Where Did the Timber Go?

Wood is one of the most important sustainable natural resources. Throughout centuries, large cities as well as regions of very high wood demand (for example, areas of salt production and iron processing) had to be supplied with wood for building and burning. One of the largest forests in Austria can be found in the National Park covering the range of mountains called “Limestone Alps.” Within this region, a wide network of dams was set up to transport single logs (“Holztrift”). Due to the dendrochronological dating of the surviving dams, regional chronologies spanning a length of almost 600 years for Norway spruce, Silver fir and European larch were set up. These chronologies serve as the background for dendro-provenancing timber. Dendro-provenancing checks the similarities between samples and different regional chronologies. The highest statistical figures give hints of the origins of the wood. Archival analyses show that many logs were transported to Vienna as rafts. For example, in 1865, more than 1504 rafts arrived in Vienna, all from different origins. The logs were used as building material as well as for burning. Further archival analyses showed that logs from this region were also used for building the roof of the Hofburg Castle in Vienna. Several hundred samples from the roof construction were dendrochronologically dated and used for dendro-provenancing. The origin of the logs was confirmed to be the wider region of the Northern alpine foothills. This meant that rafts from the rivers Alm and Traun as well as from the rivers Steyr and Enns had floated down to Vienna.

Evidence for Glacial Refugia of the Forest Understorey Species Helleborus niger (Ranunculaceae) in the Southern as Well as in the Northern Limestone Alps

Glacial refugia of alpine and subnival biota have been intensively studied in the European Alps but the fate of forests and their understory species in that area remains largely unclear. In order to fill this gap, we aimed at disentangling the spatiotemporal diversification of disjunctly distributed black hellebore Helleborus niger (Ranunculaceae). We applied a set of phylogeographic analyses based on restriction-site associated DNA sequencing (RADseq) data and plastid DNA sequences to a range-wide sampling of populations. These analyses were supplemented with species distribution models generated for the present and the Last Glacial Maximum (LGM). We used exploratory analyses to delimit genomically coherent groups and then employed demographic modeling to reconstruct the history of these groups. We uncovered a deep split between two major genetic groups with western and eastern distribution within the Southern Limestone Alps, likely reflecting divergent evolution since the mid-Pleistocene in two glacial refugia situated along the unglaciated southern margin of the Alps. Long-term presence in the Southern Limestone Alps is also supported by high numbers of private alleles, elevated levels of nucleotide diversity and the species’ modeled distribution at the LGM. The deep genetic divergence, however, is not reflected in leaf shape variation, suggesting that the morphological discrimination of genetically divergent entities within H. niger is questionable. At a shallower level, populations from the Northern Limestone Alps are differentiated from those in the Southern Limestone Alps in both RADseq and plastid DNA data sets, reflecting the North-South disjunction within the Eastern Alps. The underlying split was dated to ca. 0.1 mya, which is well before the LGM. In the same line, explicit tests of demographic models consistently rejected the hypothesis that the partial distribution area in the Northern Limestone Alps is the result of postglacial colonization. Taken together, our results strongly support that forest understory species such as H. niger have survived the LGM in refugia situated along the southern, but also along the northern or northeastern periphery of the Alps. Being a slow migrator, the species has likely survived repeated glacial-interglacial circles in distributional stasis while the composition of the tree canopy changed in the meanwhile.

Geodetic-Gravimetric Monitoring of Mountain Uplift and Hydrological Variations at Zugspitze and Wank Mountains (Bavarian Alps, Germany)

In 2004, first absolute gravity (AG) measurements were performed on the top of Mt. Zugspitze (2 sites) and at the foot (1 site) and top (1 site) of Mt. Wank. Mt. Wank (summit height 1780 m) and Mt. Zugspitze (2960 m) are about 15 km apart from each other and belong geologically to different parts of the Northern Limestone Alps. Bridging a time span of 15 years, the deduced gravity variations for Zugspitze are in the order of 0.30 μm/s² with a standard uncertainty of 0.04 μm/s². The Wank stations (foot and top) show no significant gravity variation. The vertical stability of Wank summit is also confirmed by results of continuous GNSS recordings. Because an Alpine mountain uplift of 1 or 2 mm/yr cannot explain the obtained gravity decline at Zugspitze, the dominating geophysical contributions are assumed to be due to the diminishing glaciers in the vicinity. The modelled gravity trend caused by glacier retreat between epochs 1999 and 2018 amounts to 0.012 μm/s²/yr at both Zugspitze AG sites. This explains more than half of the observed gravity decrease. Long-term variations on inter-annual and climate-relevant decadal scale will be investigated in the future using as supplement superconducting gravimetry (installed in 2019) and GNSS equipment (since 2018).

Geodetic-Gravimetric Monitoring of Mountain Uplift and Hydrological Variations at Zugspitze and Wank Mountains (Bavarian Alps, Germany)

In 2004, first absolute gravity (AG) measurements were performed on the mountain tops of Mt. Zugspitze (2 sites) and Mt. Wank (1 site), and at the Wank foot (1 site). Wank (summit height 1780 m) and Zugspitze (2960 m) are about 20 km apart from each other and belong geologically to different parts of the Northern Limestone Alps. Bridging a time span of 15 years, the deduced gravity variations for Zugspitze are in the order of 0.30 μm/s² with a standard uncertainty of 0.04 μm/s². The Wank stations (foot and top) show no significant gravity variation. The vertical stability of Wank summit is also confirmed by results of continuous GNSS recordings. Because an Alpine mountain uplift of 1 or 2 mm/yr cannot explain the obtained gravity decline at Zugspitze, the dominating geophysical contributions are assumed to be due to the diminishing glaciers in the vicinity. The modelled gravity trend caused by glacier retreat between epochs 1999 and 2018 amounts to -0.012 μm/s²/yr at both Zugspitze AG sites. This explains more than half of the observed gravity decrease. Long-term variations on inter-annual and climate-relevant decadal scale will be investigated in the future using as a supplement superconducting gravimetry (installed in 2019) and GNSS equipment (since 2018).

Dialektik der Erschließung: The German–Austrian Alps between Exploration and Exploitation

Focusing on the so-called Nördliche Kalkalpen or Northern Limestone Alps of Germany and Austria, I will discuss how human interaction with these mountains during the age of the Anthropocene shifts from scientific and athletic exploration to commercial and industrial exploitation. More specifically, I will examine travel narratives by the nineteenth-century mountaineers Friedrich Simony and Hermann von Barth, juxtaposing their respective experiences in diverse Alpine subranges with the environmental history of those regions. This juxtaposition harbors a deeper paradox, one that can be formulated as follows: Whereas Simony and Barth both rank as historically important Erschließer of the German and Austrian Alps, having explored their crags and glaciers in search of somatic adventure and geoscientific knowledge, these very sites of rock and ice were about to become so erschlossen by modernized tourism that one wonders where the precise boundaries between individual-based discovery and technology-driven development lie. In other words, during the nineteenth century a kind of Dialektik der Erschließung (a variation on Horkheimer and Adorno’s Dialektik der Aufklärung) manifests itself in the increasing anthropogenic alteration of the Alps.

The Fate of Bryophyte Sporophytes—Phenology and Vectors of Buxbaumia viridis in the Kalkalpen National Park, Austria

Knowledge about the epixylic moss Buxbaumia viridis has increased significantly due to the monitoring obligation under the Habitats Directive. However, there are still open questions about its dispersal, as the wind plays a limited role in forest ecosystems, and vectors have been suspected but not yet studied systematically for this species. Here, we present data on potential vectors of Buxbaumia viridis collected for the first time with the help of cameras, completed by monitoring the fate of sporophytes during their life cycle in the Limestone Alps National Park in Austria over a period of two years. Young, green sporophytes appeared mainly in autumn, with the highest number in October. Most of them survived winter and spring but did not exceed the age of 14 months. The sharpest decline in capsules occurred in summer when mature, and the lowest number of sporophytes appeared at the end of August. Most likely, mice seem to be responsible for this loss, as the photos from the wildlife cameras suggest, and should be considered both as predators and vectors. Birds should be considered as vectors, too. In summary, most of the reproductive biomass is sacrificed in favor of more effective dispersal, including over longer distances.

Biotic and abiotic controls on carbon storage in aggregates from grassland soils in the Northern Limestone Alps of Germany

<p>Alpine and pre-alpine grassland soils in Bavaria provide important ecosystem services and are hotspots for soil organic carbon (SOC) storage.  However, information on the underlying factors that control SOC stabilization via soil aggregation is limited. In three grassland soils with the same parent material but at different elevation (Fendt: 600 m.a.s.l, Graswang: 860 m a.s.l and Esterberg: 1,260 m a.s.l), we studied the soil aggregate distribution and associated SOC according to aggregate size classes (large-macroaggregates > 2,000 µm, small-macroaggregates 250-2000 µm, microaggregates 63-250 µm, silt plus clay particles <63 µm). Furthermore, the biomass and abundance of different ecological groups of earthworms were determined. Our results showed an increase in SOC contents and aggregate stability with elevation. SOC and N stocks of bulk soils showed the same trend as OC contents in aggregates.  Principal component analysis revealed that carbonates, SOC, aboveground plant biomass and the earthworm biomass are the main facilitating agents of aggregation and SOC and N storage in grassland soils of the Northern Limestone Alps of Germany</p>

The Eastern Austrian Alps – Their Exceptional Demographic Status in the Alpine Region

In most Alpine regions with current negative migratory balance, new in-migration from urban areas has meanwhile become a relevant factor. However, this phenomenon is insignificant in Austria’s Eastern Alps. The aim of this thesis-led work is to empirically demonstrate the main reasons for this demographically exceptional position. The Styrian-Lower Austrian Limestone Alps, representing the peripheral core area of Austria's Eastern Alps, were chosen as the study area, as in this region the population decline and above all, migratory losses are particularly high. Through various qualitative and quantitative data acquisition techniques it was shown that new inmigration is still insignificant. The main reasons for this are the perseverance of large estates and the dominance of forestry.