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The article describes the construction of flood resistant weir which is used to monitor fish migration in small and medium sized rivers. It is stated that the weir consists of a linked array of picket fence like panels made of poly vinyl chloride (PVC) tubes closed at both ends. The upstream end of each panel is fixed to concrete lattice girders and the downstream end is lifted above the water surface. This system is widely used for fish migration studies in Austria and Germany.

The effect of restoring connectivity for fish by the construction of 11 fish ladders in the Pielach and Melk rivers, both tributaries to the Danube in Austria, was monitored using electric fishing and fish traps between 1999 and 2004. In order to assess the efficiency of connectivity rehabilitation measures pre- and post-project data combining electric fishing and trap catch data were analyzed by means of three fish-based assessment methods: a MUlti-Level concept for a Fish-based, river-type-specific Assessment of ecological integrity (MULFA), the Fish Index Austria (FIA) and the European Fish Index (EFI). The effect of adding qualitative trap catch data to electric fishing data on metrics and indices was also tested and the magnitude of the effect was related to the distance of the sites from the river mouth. The results clearly demonstrated the significant contribution of connectivity rehabilitation measures to the ecological integrity of rivers like the River Pielach where morphological conditions are good, whereas remaining channelization still limits the success of connectivity measures in the River Melk. Trap catch data were found to represent an essential source of additional information to assess the efficiency of connectivity measures shortly after their implementation. The negative correlations of the magnitude of the effect of different indices and metrics with the distance of assessment sites from river mouths obviously underline the importance of the river Danube as a source for the re-colonization process. While the indices tested were found to have limited ability to reflect short-term response of fish assemblages to continuum rehabilitation, guild metrics were able to detect improvements of the ecological status shortly after the implementation of connectivity measures. Six metrics showed significant differences between pre and post-project data reflecting the expected increase of the ecological integrity: (1) Fish Region Index (FRI; FIA, MULFA), (2) number of subdominant species and (3) number of flow-guilds (FIA), (4) number of type specific species (MULFA), (5) number of benthic species and (6) number of potamodromous species (EFI); the FRI differences were only significant when trap catch data were added. The EFI indicated a decline of ecological integrity through increases in the density of omnivorous species and the relative number of tolerant species as well as a decrease in the relative number of intolerant species. Significantly decreasing responses with the distance from the river mouth were documented by the EFI and MULFA-index, the FRI (FIA, MULFA), total biomass and for the number of type specific species (MULFA). [ABSTRACT FROM AUTHOR]

Between April and November 2003, parasitological examinations of the nase Chondrostoma nasus L. and the chub Leuciscus cephalus L. from the neighbouring Melk and Pielach rivers in Lower Austria were conducted. Amongst various gill parasites, Lamproglena pulchella Nordmann 1832 was detected on both fish species, which was the first record of this parasitic crustacean in Austria. Physico-chemical examinations of water samples of the two rivers were carried out during the same period. The results indicate that general water parameters in the Melk were subjected to more vigorous changes than in the Pielach. Critical temperature levels and ammonia concentration as well as drastic changes in the ionic composition occurred more frequently in the Melk River. The observed distribution of L. pulchella indicates its sensitivity to such stress factors: there was no evidence of the parasite in the Melk River until late November and it only then occurred on the gills of L. cephalus with a prevalence of 20% and a mean intensity of 2. In the Pielach River, infestation on chub had already occurred in June with a prevalence of 40% and a mean intensity of 3, rising to 60% and 7 in November; 45% of the nase was also infested in November at a mean intensity of 3. [ABSTRACT FROM AUTHOR]

• Discrimination of Austrian carrots from five different regions was achieved. • Sr isotopic, multi-elemental and metabolomic data were used separately or in combination. • Mid-level data fusion allowed highly efficient and correct classification. • One-class classification was more suitable for authentication than discriminant approaches. An exploratory study for verifying regional geographical origin of carrots from specific production regions in Austria ("Genussregionen") was performed by combining chemical fingerprinting methods, namely n (86Sr)/ n (87Sr) isotope amount ratios, multi-elemental and metabolomic pattern. Chemometric classification models were built on individual and combined datasets using (data-driven) soft independent modelling of class analogies and (orthogonal) projections to latent structures-discriminant analysis to characterise and differentiate carrots grown in five regions in Austria. A predictive ability of 97% or better (depending on the classification technique) was obtained using combined Sr isotope amount ratios and multi-elemental data. The use of data fusion strategies, in particular the mid-level option (fusion of selected variables from the different analytical platforms), allowed highly efficient (99–100%, except soft independent modelling of class analogy with 97%) and correct classification of carrot samples. [ABSTRACT FROM AUTHOR]

Elemental and isotopic pattern of n( 87 Sr)/n( 86 Sr) and δ 88 Sr/ 86 Sr SRM987 were used to characterise groundwater and recharge of saline ponds in a clastic aquifer in East Austria. Therefore, shallow, artesian and thermal groundwaters of the investigated aquifer along with rainfall and rivers were analysed using (MC) ICP-MS. The n( 87 Sr)/n( 86 Sr) ratio and elemental pattern changed with aquifer depth as a result of progressing bedrock leaching and dissolution with increasing groundwater residence time. The n( 87 Sr)/n( 86 Sr) ratio of shallow groundwater below saline ponds of 0.71019 ± 0.00044 was significantly different from thermal groundwater of 0.71205 ± 0.00035 (U, k = 2). In contrast to previous theories, this result suggested no recharge of saline ponds by upwelling paleo-seawater. Isotope pattern deconvolution revealed that rainfall accounted to about 60% of the n( 87 Sr)/n( 86 Sr) ratio of shallow groundwater below saline ponds. The δ 88 Sr/ 86 Sr SRM987 values of groundwater decreased from about 0.25 ‰ in most shallow, to predominantly negative values of about -0.24 ‰ in artesian groundwater. This result indicated leaching and dissolution of weathered minerals. In turn, the δ 88 Sr/ 86 Sr SRM987 of deep thermal groundwater showed positive values of about 0.12 ‰, which suggested removal of 86 Sr from solution by carbonate precipitation. These results highlight the potential of δ 88 Sr/ 86 Sr SRM987 signature as an additional geochemical tracer.

In recent decades, an increasing number of studies have aimed to shed light on the origin and spread of tuberculosis in past human populations. Here we present the results of a systematic palaeodemographic and palaeopathological survey of the Early Mediaeval population of Gars/Thunau (Lower Austria), which - at this stage - includes 373 individuals recovered at two archaeological sub-sites: a fortified settlement (including a necropolis) at the top of a hill - probably reserved for social and military elites; and a large riverine settlement at the foot of the hill, a so-called 'suburbium', where burials and an area of 'industrial' character were discovered. We recorded a great number of pathological alterations and a variety of 'classical' features of tuberculosis, such as vertebral destructions (Pott's disease) and joint destructions, and other pathological (unspecific) features probably linked with Mycobacterium tuberculosis infection (e.g. new bone formation at the inner surface of the ribs, endocranial alterations in the form of 'pits', and new bone formation at the cranial base). We hypothesize that the two contemporaneous (∼900-1000 AD) populations of Gars/Thunau differed not only in their social affiliation/condition, but also in the type and frequencies of their population-density-related infectious diseases (in particular tuberculosis). Moreover, we investigated the molecular genetic evidence of the causative organism in a few selected immatures exhibiting pathological changes at the inner wall of the cranium and discuss these findings in regard to the macroscopic features observed. Finally, we analysed carbon and nitrogen stable isotopes of both populations and strontium isotope ratios of the hill-top inhabitants in order to reconstruct certain aspects of diet and mobility to test our hypothesis concerning the specific social and/or military character of the site., (Copyright © 2015 Elsevier Ltd. All rights reserved.)