Die Regenwurmfauna (Oligochaeta: Lumbricidae) der Aue der Großen Kokel als Abhängige der Böden im Flusseinzugsgebiet und der Auengradienten

In five floodplain transects along the course of the river Târnava Mare in Rumania, 17 earthworm species werecounted. The species spectrum of the earthworm fauna of the studied floodplains is dependent on the provenance of thefloodplain sediments. On the basis of this provenance, the fauna of three groups of soil localities on the floodplain aredifferentiated: in the upper reaches of the river, the fauna of the floodplain soils derived from brown forest soils and podzolicsoils (near Sub Cetate); on the eastern side of the middle reaches, the fauna of the soils mainly derived from gray-brown podzolicsoils (near Porumbenii Mari, Hoghilag); and on the western side of the middle reaches and the lower reaches, the fauna of thesoils principally derived from planosols (near Alma, Valea Lungă). Proctodrilus tuberculatus occurs in the floodplain sedimentspredominantly derived from the gray-brown podzolic soils, and in those parts of the floodplain derived from planosols P.opisthoductus and Aporrectodea georgii are found. Ap. georgii and Allolobophora leoni are mostly mutually exclusive in thefloodplain transect, were they are apparently indicator species of sediment deposition close to the river and/or the effect of highwater on the soil chemistry. P. tuberculatus and P. opisthoductus occur as vicarious species in the soil profile of the area wheretheir distribution overlaps. Three soil factors that are significant in determining earthworm distribution are emphasized:lessivage, or translocation of clay; the pervection of colloidal organic matter (humus) into the soil, and the texture of the soillayers resulting from sedimentation. An additional record of the new species P. thaleri is given

Zur Regenwurmfauna (Oligochaeta: Lumbricidae), insbesondere zur Proctodrilus-Verteilung, in den Auen der Tschernosem- und Parabraunerde-Gebiete beiderseits des Erzgebirges

On the earthworm fauna (Oligochaeta: Lumbricidae), in particular the distribution of Proctodrilus, in the floodplains of the chernozem and gray-brown podzolic soil areas on both sides of the Ore Mts. In a study of mineral soils in floodplains, shallow depressions, and dry valley heads of the Saale-Elster plateau in eastern Germany and along the lower Eger/Ohře river in Czechia, sixteen earthworm species were found. On the basis of these findings, areas of gray-brown podzolic soils can be differentiated from chernozem areas mainly by the occurrence in the former of the two species Proctodrilus antipai and P. tuberculatus. In a section of one floodplain in the gray-brown podzolic soil area, the distribution of these two earthworm species shows a vicariance situation, such that P. antipai is restricted to the outer edges of the floodplain while P. tuberculatus inhabits the parts close to the river. In the chernozem areas, on the other hand, P. antipai is the only one of the two species to occur, and is also found in those areas close to the river. P. tuberculatus disappears in the transitional zone between a floodplain where it occurs and a chernozem floodplain. The distribution of P. antipai ends where a floodplain inhabited by it graduates into one belonging to a large river with a high rate of flow. On the stretch of the Elbe near Mlékojedy, where the position of the confluence with the Ohře has migrated over time, the vicariant distribution of the two species within the soil profile was noted. Here P. antipai is found in the uppermost soil layer, while P. tuberculatus lives in the lower-lying mineral soil at the same location. This ecological vicariance appears to represent different stages of clay translocation in flood loam. The results show that P. tuberculatus is dependent on such clay translocation or lessivage, and where this soil-profile-influencing process cannot take place the species does not occur. Examples would be oligotrophic acid montane brown forest soils, eutrophic brown forest soils, and chernozems, as well as the floodplain soils derived from all three

Der Regenwurm Proctodrilus tuberculatus (Černosvitov, 1935) auf Hangschultern der mitteldeutschen Lössrandstufe (Oligochaeta: Lumbricidae) = The earthworm Proctodrilus tuberculatus (Černosvitov, 1935) on the crest of slopes in the central-German loess-edge ramp (Oligochaeta: Lumbricidae)

The distribution of Proctodrilus tuberculatus (Černosvitov) along the line of gradient (fall line) on the slopes of the central-German loess-edge ramp (Lössrandstufe) was investigated. The highest density on loess-edge ramps reached by the species (max. 47 adults/0.25 m²) was on the crest of slopes where the fall line of the slope merges with the plateau of the culmination area. In these locations the occurrence of surface runoff along the fall line of the slope is at its lowest and percolation into the soil profile at its highest. The soil depth in the luvisol preferred by P. tuberculatus lies in the transition zone of the A1/Bt horizons, which are influenced by soil leaching (lessivage) and conspicuously marked by the presence of many argillans. The dietary strategy of P. tuberculatus is apparently a specialisation in that the species extracts its nutrition principally from the mineral part of the soil profile in luvisols. It seems that the channels in the luvisol, which are filled with muddy sediment, are advantageous to the endogeic P. tuberculatus as it moves through the soil and feeds. In the A1/Bt layer this species probably takes up pluviolessivate, which contains microorganisms and finely dispersed or unstable organic and mineral components. This means that the ecological niche of the species is determined by the movements of nutritional material in the soil. Aporrectodea caliginosa (Sav.) and Ap. rosea (Sav.), which were always found in association with the species in the loess slopes studied, can contribute to the flow of nutrients in the mineral part of the profile by their finely dispersed particles of excrement

Multi layered shotcrete design for tunnel construction

Shotcrete linings have been applied successfully for a large number of tunnel constructions within the last couple of decades all around the world. While up to the 1980’s the structural design of the shotcrete linings mainly was based on experience gathered throughout the construction and some simplified analyses in the following years the application of the Finite Element Method lead to much more sophisticated design and more accurate estimation of deformations and stress state in the shotcrete lining. This was amongst others achieved by considering the time and construction sequence - dependent development of the deformations as well as by applying simplified time dependent material laws for shotcrete. The design verification as such is commonly done by using the methods as stated in Eurocode 2 for ULS and SLS. The design becomes even more complex for cases in which during a first construction stage one shotcrete layer is applied and stressed and only later additional, stress free layers are applied in order to carry additional loads caused by further construction stages. With such situations tunnel designers have to deal frequently in cases when cross sections between two main tunnels need to be installed or a second, parallel tunnel is driven while the first tunnel is already in place. Within this paper the special case of such multi – layer shotcrete linings is discussed and proposals for the calculation of the stress state in the lining and the design verification are made

Untersammelsdorf Tunnel – Challenges, Special Measures and use of Special Shotcrete for Tunneling in Lacustrine Clay

The 665 m long, twin-track Untersammelsdorf Tunnel is being built in the course of the construction of the Koralmbahn line between Graz and Klagenfurt. The tunnel is located in extremely challenging subsoil conditions consisting of silty to fine sandy lacustrine deposits. The developed tunneling concept provided wide-ranging special underground engineering measures as piling, jet grouting and temporary struts and represents a unique construction method to date. Accordingly, numerous challenges arose in the design phase, which could be verified by carrying out extensive trials and investigations in the preparatory period or for which fallback levels had to be provided for the support system. Please click Additional Files below to see the full abstract

SyntEO: Synthetic training data generation for offshore wind energy infrastructure detection in Sentinel-1 imagery

Over the last decade, deep learning models have become increasingly important in the toolbox of the remote sensing community. Nevertheless, one major drawback is the necessity of large, precisely annotated training data sets in the widely used supervised optimisation approach. If a researcher wants to investigate an object class or land surface process for which no training data exists, a large amount of potential data which contains the target of interest has to be examined and annotated manually. Three major problems are related to this process, the availability of data showing the targets of interest, the time which has to be spent to explore and annotate the data, and the subjective annotation of the targets. To solve these issues, we present a synthetic data generation approach for Earth observation images called SyntEO. SyntEO is based on an ontology representing expert knowledge that describes the characteristics and relations of scene elements appearing in a remote sensing scene. Thereby, the domain expert does not include single fixed values to describe the characteristics of scene elements but multiple values contained in ranges, distributions or sample databases. That way, a data generator can combine highly variable scene element characteristics. An image generator uses the ontology to compose a two-dimensional, discrete scene composition. In a proceeding step, the texture is added to the discrete scene composition to generate the final image. The desired annotation is derived from the scene elements, which are defined as targets at the same time. To provide an intuition of an entire SyntEO workflow, we present the generation of synthetic Sentinel-1 scenes which show coastal areas and annotated offshore wind energy infrastructures. The synthetic training examples are then used to train a convolutional neural network in order to detect offshore wind energy infrastructure in real-world Sentinel-1 imagery on a global scale

VALIDATING GLOBAL STRUCTURAL DAMPING MODELS FOR DYNAMIC ANALYSES

Abstract: Finite Element (FE) models grow in terms of detail and complexity. They strive to provide a more precise mass and stiffness distribution in order to achieve better load prediction capabilities. However, they also need to include damping models to achieve better results for dynamic loads analyses. This is why experiments are usually carried out to quantify global damping ratios of the final structure and include them in the analytical model for further calculations. Yet, especially for large aerospace structures assembled from different substructures, the experimental determination of damping ratios for the assembled structure may be impossible or ineconomical. Therefore, a consistent approach to predict the damping properties of assembled structures is desirable. In this work, FE models of a laboratory test structure and its two substructures are built up. Modal tests are carried out on the substructures. On the basis of correlated substructure modal damping ratios, global proportional damping models are applied on substructure level in order to build proportional substructure damping matrices, construct a nonproportional, full structure damping matrix and thus predict the damping properties for the fully assembled structure. The approach is validated with the help of experimental results from a modal test on the fully assembled laboratory test structure. Because of the unsatisfactory reproduction of the substructure damping properties by the selected damping models and the outcome for the assembled structure in this work, an additional investigation on computational model updating of damping parameters on substructure level is carried out on a simulated plate