Benthic invertebrate neozoa in Austrian rivers

Neozoa werden als gebietsfremde Arten definiert, welche nach 1492 direkt oder indirekt durch den Menschen eingeführt wurden und selbstreproduzierende Populationen zu bilden im Stande sind (Essl & Rabitsch 2002). Biologische Invasionen sind schon seit dem Zeitalter des Kolonialismus ein bekanntes Phänomen, gegenwärtig hat das Problem in einer Zeit der Globalisierung von Wirtschaft und Tourismus und einer globalen Klimaveränderung jedoch eine neue Dimension und Geschwindigkeit erreicht. In Österreich gibt es grundsätzlich eine gute Datenbasis über das Auftreten von benthischen Einwanderern. Bereits in der älteren Literatur findet man dazu einige Hinweise, z.B.: Strouhal (1939), Vornatscher (1965) und Liepolt (1965–67). Größere Aufmerksamkeit wurde dem Phänomen invasiver Arten seit der massiven Ausbreitung der Dreikantmuschel Dreissena polymorpha geschenkt, als sich diese in den 1970er Jahren in vielen Flüssen und Seen in einem sehr kurzen Zeitraum ausbreitete. Verstärkte Beachtung wurde den Neozoa in der Limnologie aber erst im letzten Jahrzehnt zuteil, als die Fundnachweise immer häufiger wurden und sowohl ökonomische als auchbemerkenswerte ökologische Auswirkungen durch invasive Arten vermutet oder nachgewiesen wurden. Beispielsweise belegte Gruber (2006), dass der autochthone Steinkrebs (Austropotamobius torrentium) bereits bis in die Quellregion hinein durch den amerikanischen Signalkrebs (Pacifastacus leniusculus) verdrängt wird. In Österreich entstand als Folge des erhöhten Problembewusstseins in den letzten Jahren eine Reihe von umfassenden Publikationen zum Thema Neobiota: „Invaders“ (Aescht & al. 1995), „Neobiota in Österreich“ (Essl & Rabitsch 2002) und „Aliens“ (Wallner 2005). Während die überwiegende Zahl der Publikationen zum Thema Neozoa von taxonomischen Fachspezialisten stammt und deshalb zumeist auf eine oder einige ausgewählte Tiergruppen beschränkt bleibt, basiert vorliegender Beitrag auf Monitoringdaten und gewässerökologischen Untersuchungen, in welchen immer die gesamte Artengesellschaft der benthischen Evertebraten erhoben wurde.Based on 9,544 data sets from 1,060 Austrian rivers and streams the paper gives a quantitative and qualitative overview of the occurrence and distribution of benthic invertebrate neozoa in Austrian running waters. Excluding those species that have been recorded only as single findings or which inhabit greenhouses with no connection to natural water bodies, a total number of 46 benthic invertebrate species can be classified as neozoa for Austria. Referred to the known number of about 3,200 benthic macro-invertebrate species the neozoa fauna comprises only a small amount of 1.8 %. On the other hand these neozoa colonise 16.1% of the investigated water bodies. Most investigation sites are inhabited by only one neozoa species. The maximum number of neozoa species found at one investigation site was not higher than 13. However, at some river sites the abundance of neobiota specimens can clearly dominate the benthic community. E. g. a maximum number of about 500,000 Corophium curvispinum individuals per m² (99% of the total abundance) with a biomass up to 0.6 kg fresh weight per m² has been observed in the River Morava (Lower Austria), a neozoa biomass of 7 kg/m2 (Corbicula fluminea) was documented in a muddy Danube harbour at Linz, Upper Austria. In contrast to the indigenous fauna, which is mainly composed of insects (85%) the neozoa fauna is dominated by Crustacea (53%) and Mollusca (24%). 47% of the neozoa species originate from European regions, mainly the ponto-caspian area. Other important donor areas are North America and South East Asia. With respect to aquatic neozoa in Austria, the River Danube can be clearly identified as the main immigration channel of the ponto-caspian (most of the Mollusca and Crustacea neobiota species) as well as the mediterranean fauna (Atyaephyra desmaresti) and other species that spread via Western Europe, respectively. Although most of the benthic invertebrate neozoa have never left the main Danube channel, a steady immigration from Danube tributaries by some species has been observed in the last years

Composition and dynamic of benthic macroinvertebrates community in semi-arid area rivers of Burkina Faso (West Africa)

The benthic macroinvertebrates communities dynamic were investigated in rivers from Burkina Faso in the purpose to analyze the taxonomic composition, the structure of benthic macroinvertebrates community and the composite environmental variables that correspond to the major distribution patterns of this community. The results showed that a total of 132 taxa was recorded and the large majority of these (103 taxa) belonged to 57 families from 8 orders of insects that represent 95% of relative abundance. We also observed some distinct differences relative to the spatial and temporal variation in the taxonomic composition. The canonical correspondance analysis (CCA) revealed a strong correlationship between Chironomidae, Syrphidae, Culicidae, Psychodidae, as well as the Pulmonates molluscs and organic nutriments feeding dynamics. These findings showed the sensitivity of benthic macroinvertebrates at different level: sensitivity which could be attributable to man-induced activities.© 2016 International Formulae Group. All rights reserved.Keywords: Benthic macroinvertebrates, enviromental variables, dynamic, Burkina Fas

An HIV-1 clade C DNA prime, NYVAC boost vaccine regimen induces reliable, polyfunctional, and long-lasting T cell responses

The EuroVacc 02 phase I trial has evaluated the safety and immunogenicity of a prime-boost regimen comprising recombinant DNA and the poxvirus vector NYVAC, both expressing a common immunogen consisting of Env, Gag, Pol, and Nef polypeptide domain from human immunodeficiency virus (HIV)-1 clade C isolate, CN54. 40 volunteers were randomized to receive DNA C or nothing on day 0 and at week 4, followed by NYVAC C at weeks 20 and 24. The primary immunogenicity endpoints were measured at weeks 26 and 28 by the quantification of T cell responses using the interferon γ enzyme-linked immunospot assay. Our results indicate that the DNA C plus NYVAC C vaccine regimen was highly immunogenic, as indicated by the detection of T cell responses in 90% of vaccinees and was superior to responses induced by NYVAC C alone (33% of responders). The vaccine-induced T cell responses were (a) vigorous in the case of the env response (mean 480 spot-forming units/106 mononuclear cells at weeks 26/28), (b) polyfunctional for both CD4 and CD8 T cell responses, (c) broad (the average number of epitopes was 4.2 per responder), and (d) durable (T cell responses were present in 70% of vaccinees at week 72). The vaccine-induced T cell responses were strongest and most frequently directed against Env (91% of vaccines), but smaller responses against Gag-Pol-Nef were also observed in 48% of vaccinees. These results support the development of the poxvirus platform in the HIV vaccine field and the further clinical development of the DNA C plus NYVAC C vaccine regimen

Gewässerbeurteilung und Immissionsschutz

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Assessing the Ecological Integrity of Running Waters

Abstract Mayflies (Ephemeroptera) play an important role in almost all undisturbed freshwater communities and their larvae frequently form a considerable part of the material sampled during biomonitoring procedures. Mayfly taxa are widely accepted as bioindicators for water quality and form an integral part of standardized systems for the saprobic evaluation of running waters. Nevertheless, successful interpretation of data depends heavily on sampling strategies and the technical concepts adopted therein. The following paper discusses current problems affecting the correct assessment of mayfly community structure and proposes basic requirements to improve the meaningfulness of limnological routine sampling with regard to Ephemeroptera. The topics covered include: mayfly diversity in different types of freshwater communities in Europe; natural habitats and sampling sites / sampling strategies; life cycles and minimum sampling frequency; level of identification and interpretation of data

Assessing the Ecological Integrity of Running Waters

Abstract Mayflies (Ephemeroptera) play an important role in almost all undisturbed freshwater communities and their larvae frequently form a considerable part of the material sampled during biomonitoring procedures. Mayfly taxa are widely accepted as bioindicators for water quality and form an integral part of standardized systems for the saprobic evaluation of running waters. Nevertheless, successful interpretation of data depends heavily on sampling strategies and the technical concepts adopted therein. The following paper discusses current problems affecting the correct assessment of mayfly community structure and proposes basic requirements to improve the meaningfulness of limnological routine sampling with regard to Ephemeroptera. The topics covered include: mayfly diversity in different types of freshwater communities in Europe; natural habitats and sampling sites / sampling strategies; life cycles and minimum sampling frequency; level of identification and interpretation of data

Increased cave use by butterflies and moths: a response to climate warming?

Between 2015 and 2019, the list of Lepidoptera from “cave” habitats (i.e., proper caves, rock shelters and artificial subterranean structures) in Austria grew from 17 to 62 species, although the effort of data collection remained nearly constant from the late 1970s onwards. The newly recorded moths and butterflies were resting in caves during daytime in the the warm season, three species were also overwintering there. We observed Catocala elocata at 28 cave inspections, followed by Mormo maura (18), Catocala nupta (7), Peribatodes rhomboidaria, and Euplagia quadripunctaria (6). More than half of the species have been repeatedly observed in caves in Austria or abroad, so their relationship with such sites is apparently not completely random. Since the increase of records in Austria coincided with a considerable rise in the annual number of hot days (maximum temperatures ≥30°C) from 2015 onwards, we interpret the growing inclination of certain Lepidoptera towards daytime sheltering in caves as a behavioral reaction to climate warming

A Europe-wide system for assessing the quality of rivers using macroinvertebrates: the AQEM Project*) and its importance for southern Europe (with special emphasis on Italy)

The AQEM Project aims to develop a Europe-wide system for monitoring the ecological quality of rivers using macroinvertebrates, to satisfy the requirements of the EU Water Framework Directive. Three main types of anthropogenic perturbation are being investigated: morphological degradation, water (organic) pollution and acidification (the last is not under investigation in Italy). The selection of reference and impaired study sites is discussed. Particular attention is paid to the problems encountered when defining reference conditions. The initial stages of the project highlighted the lack of a Europe-wide definition of river types. The future development of such a typology from the AQEM database is discussed. The standard AQEM data gathering methods are presented, from background information about sites to the microhabitat-based macroinvertebrate sampling method. The extended fieldwork methods used in Italy are described. These included the separate analysis of the invertebrate assemblages from each replicate, the recording of additional microhabitat variables for each replicate and the completion of large-scale survey techniques for each site (including RHS). The extended method was designed to enhance the important ecological information available from the dataset, particularly relevant in Italy where significant gaps exist in the taxonomic and ecological knowledge of many macroinvertebrate taxa. Preliminary and expected findings are presented, including examples of the range and habitat selection of two species of Ephemeroptera endemic to Italy, as well as data relating to the number of taxa found at a site with increasing numbers of microhabitat replicates taken. The importance of the AQEM Project not only for biomonitoring, but also for ecology, taxonomy and conservation, in Italy and for the south of Europe in general, is emphasised