Graf Wolfram

BOKU University | boku · Institute of Hydrobiology and Aquatic Ecosystem Management

Obwohl die Biodiversitätskrise immer stärker ins öffentliche Bewusstsein tritt, wird der Artenverlust unter der Wasseroberfläche meist kaum wahrgenommen und dies trotz der Tatsache, dass aquatische Ökosysteme wesentlich stärker als terrestrische bedroht sind. Die im Rahmen vorliegender Arbeit ausgewählten Artengruppen spiegeln die Gesamt-heit der w...

Background Although studies of the entomofauna of the Balkan Peninsula have increased in quantity and intensity over the course of the last decades, many areas are still not fully investigated regarding their faunistic inventory. New information As a result of a field trip in the Vjosa catchment in 2023, a new species of the genus Protonemura Kemp...

Most of the world’s rivers are shaped by interacting social and natural processes. As Industrialised Riverine Landscapes (IRLs), they have become part of our critical infrastructure, vital for the water-energy-food nexus, but also subject to extreme events and vulnerable to biodiversity loss in the wake of global change. This situation poses major...

Zusammenfassung Die Modellierung von aquatischen Lebensräumen gewinnt durch die verschiedenen Zielvorgaben auf europäischer und somit auch nationaler Ebene immer mehr an Bedeutung. Neben den Vorgaben der Wasserrahmenrichtlinie und den Zielen zum Ausbau der erneuerbaren Energieträger, inkl. Wasserkraft, sind es auch die neuen Strategien zur Biodiver...

Low-order streams contribute to the abiotic and biotic character of large rivers and are renowned for harboring unique forms of aquatic flora and fauna. However, most studies on headwater streams mainly focus on the mainstems and overlook the contribution of the tributary systems. Moreover, low-order streams are generally overlooked in legislation...

Aim Habitat templet theory predicts that the functional niches of species evolved in response to selection pressures imposed by each species' spatial–temporal environment. Consequently, similar environmental conditions should lead to convergence in the biological trait composition of biogeographically independent assemblages. Given their high diver...

Habitat niches of fish species can exert a strong influence on population structure, even on a small geographical scale. In this scope, Pelasgus thesproticus is a great model species to study connectivity in riverine environments owing to its naturally patchy habitat distribution. Furthermore, it is important to conduct such studies in near-natural...

Within the upper Neretva catchment in Bosnia several hydropower plants are projected. Between 28.6. and 1.7.2022 a baseline survey was initiated to screen the area regarding the diversity of aquatic insects and its linked conservation value. In total, 59 Trichoptera species, ten Plecoptera species, 19 Ephemeroptera and 16 Diptera (Tipuloidea) speci...

For the stone crayfish, a threatened species listed in the Habitats Directive in Annex II and V, three monitoring methods were evaluated: hand capture by day, hand capture by night and eDNA sampling respectively. The lack of a standardized sampling method in Austria and the simultaneous obligation to monitor and report on the status of protected sp...

Streams represent a special case of directional environmental gradients where ecological opportunity for diversification may be associated with upstream and downstream dispersal into habitats that differ in selective pressures. Temperature, current velocity and variability, sediment erosion dynamics and oxygen saturation are key environmental param...

Increased turbulent flow and sediment transport during flood or hydropeaking events often induces rapid changes in underwater sound pressure levels, which is here referred to as soundpeaking. This study is the first to investigate such a change in the underwater soundscape in relation to fish behavior using an experimental approach. Trials were con...

Owing to a long history of anthropogenic pressures, freshwater ecosystems are among the most vulnerable to biodiversity loss¹. Mitigation measures, including wastewater treatment and hydromorphological restoration, have aimed to improve environmental quality and foster the recovery of freshwater biodiversity². Here, using 1,816 time series of fresh...

The access to an adequate quantity and quality of water is vital to sustain healthy ecosystems and human socioeconomic development. However, the shift from an agrarian, solar energy based to an industrialized, fossil fuel‐based socio‐metabolic regime has put natural water resources under stress and led to dramatic transformations of riverine landsc...

Aim Understanding biodiversity patterns is crucial for prioritizing future conservation efforts and reducing the current rates of biodiversity loss. However, a large proportion of species remain undescribed (i.e. unknown biodiversity), hindering our ability to conduct this task. This phenomenon, known as the ‘Linnean shortfall’, is especially relev...

Description of Leuctra papukensis; re-description of Leuctra signifera and Leuctra austriaca.

The cranefly (Tipuloidea) fauna of the Western Balkans is still poorly known. In this study, occurrence data of 77 species is reported, of which two species are newly recorded for Albania, eight species for Bosnia and Herzegovina, twelve for Croatia, and seven for Slovenia, respectively. A new species, Baeoura neretvaensis Kolcsár & d’Oliveira, sp....

Motivation Aquatic insects comprise 64% of freshwater animal diversity and are widely used as bioindicators to assess water quality impairment and freshwater ecosystem health, as well as to test ecological hypotheses. Despite their importance, a comprehensive, global database of aquatic insect occurrences for mapping freshwater biodiversity in macr...

The Ziller River, a tributary to the Inn in Tyrol, Austria, is affected by hydropower generation. Macroinvertebrate habitat‐preferences were investigated in the field and corresponding habitat suitability curves were applied successfully to a novel integrative assessment method based on hydrodynamic modelling. Here, a reach of the Ziller River is s...

Summary: Biodiversity in the Biosphere Reserve Carinthian Nockberge. Results from the 6th GEO day of Nature 2021 – “At the foot of the Zunderwand” Seventy-one biodiversity experts participated in the inventory of plant, fungi and animal species from the area beneath the Zunderwand on the 2nd and 3rd of July 2021. The study area is situated in the C...

Hydropeaking operation leads to fluctuations in wetted area between base and peak flow and increases discharge-related hydraulic forces (e.g. flow velocity). These processes promote macroinvertebrate drift and stranding, often affecting benthic abundance and biomass. Our field experimental study—conducted in three hydropeakingregulated Swiss rivers...

Globalization has led to the introduction of thousands of alien species worldwide. With growing impacts by invasive species, understanding the invasion process remains critical for predicting adverse effects and informing efficient management. Theoretically, invasion dynamics have been assumed to follow an “invasion curve” (S-shaped curve of availa...

Floodplain assessment systems that conform to the Water Framework Directive hardly exist in Europe at present. Currently available methods are limited to the main channel and thus contradict a holistic view of a river ecosystem approach. Especially the large central European rivers such as the Danube, Rhine or Elbe have undergone massive changes in...

Bei den 10 ABOL-BioBlitz-Aktionen im Rahmen der Tage der Artenvielfalt 2019 und 2020, die großteils in Schutzgebieten stattfanden, wurden DNA-Barcodes von Or-ganismen erstellt, die im Zuge der Veranstaltungen gesammelt und bestimmt wur-den. Im Rahmen dieser Publikation werden insgesamt 2.172 Datensätze bzw. 1.750 DNA-Barcodes von 1.040 Arten veröff...

The hydrological regime of many alpine rivers is heavily altered due hydroelectric power generation. Hydropeaking operation produces frequent and irregular discharge fluctuations. Depending on the operational changes of flow amplitude and/or up‐ramping rate as well as on river morphology, hydropeaking can lead to quick and strong variations in hydr...

Hydropeaking operation leads to fluctuations in wetted area between base and peak flow and increases discharge-related hydraulic forces (e.g., flow velocity). These processes promote macroinvertebrate drift and stranding, often affecting benthic abundance and biomass. Our field experimental study – conducted in three hydropeaking-regulated Swiss ri...

Sediment dynamics and composition in streams are key factors influencing the habitat quality of aquatic organisms, consequently playing an important role in terms of river restoration. The superposition of the river-bed with fine sediments is an increasing global stressor affecting local habitat diversity and leading to changes of benthic communiti...

Rivers are dynamic ecosystems in which both human impacts and climate‐driven drying events are increasingly common. These anthropogenic and natural stressors interact to influence the biodiversity and functioning of river ecosystems. Disentangling ecological responses to these interacting stressors is necessary to guide management actions that supp...

• Use of invertebrate traits rather than species composition may facilitate large-scale comparisons of community structure and responses to disturbance in freshwater ecology because the same traits potentially occur everywhere. In recent years, comprehensive invertebrate trait databases have been established at different scales (e.g., regions, cont...

• Nymphs of all 29 described Prosopistoma species share a conspicuous synapomorphy: a round mesonotal shield, the carapace. They occur in the Palaearctic (nine species), the Oriental (12 species) and the Afrotropic as well as Australian regions (six and two species, respectively). Relatively little is known about their ecology, but past and extant...

With ongoing climate change and increasing water resource pressures, the knowledge and predictability of stream drying is essential for water management. However, the hydrological data for assessing the flow regime of temporary streams are often non-existent or scarce. The flow regime strongly affects stream ecological functioning and ecosystem pro...

River systems have undergone a massive transformation since the Anthropocene. The natural properties of river systems have been drastically altered and reshaped, limiting the use of management frameworks, their scientific knowledge base and their ability to provide adequate solutions for current problems and those of the future, such as climate cha...

Worldwide, water resources have an impact on all forms of life as lotic systems are networks that interconnect water resources and land. They are important for navigation, water supplies, agriculture, recreation, and industrial development and help to regulate changes in climate and support social, spiritual, educational, and ecosystem health servi...

Macroinvertebrates play a unique role in aquatic ecosystems by acting as processors of nutrients and organic energy from allochthonous and autochthonous sources. Within East Africa and especially Kenya, anthropogenic influences on streams and rivers as a result of deforestation and expansion of agricultural lands are pervasive. This study investiga...

Tropical communities in the developing world depend heavily on riverine systems for their socioeconomic development. However, these resources are poorly protected from diffuse pollution, and there is a lack of quantitative information regarding the microbial pollution characteristics of riverine water, despite frequently reported gastrointestinal d...

This report summarizes the value of the river Vjosa system as one of the few remaining reference sites for dynamic floodplains in Europe. The morphological floodplain of the Vjosa is characterized by an exceptionally high near-nature status, hence representing an extreme rare reference site for medium sized rivers in Europe. The high values of habi...

The rare mayfly Prosopistoma pennigerum was once widely distributed across Europe and occurred virtually in every large river. Today, it holds fast against the ever-growing destruction of its habitat with a few relic populations remaining. Preliminary data and information on its congeners suggest that free-flowing rivers with near-natural hydrodyna...

With the European Water Framework Directive (WFD) in 2000, all European countries committed themselves to restore the good ecological status or a good ecological potential in their water bodies and to prevent further deterioration of the ecological status. In the national water management plan, concrete environmental goals are defined for all water...

A wide knowledge base regarding the ecological preferences of benthic macroinvertebrates is synthesized in public databases. This knowledge can assist in disentangling the influence of multiple environmental factors on the probability of occurrence of macroinvertebrates and in identifying anthropogenic impacts on the macroinvertebrate assemblage. W...

This study tested genetic microbial source tracking (MST) methods for identifying ruminant- (BacR) and human-associated (HF183/BacR287, BacHum) bacterial faecal contaminants in Ethiopia in a newly created regional faecal sample bank (n = 173). BacR performed well, and its marker abundance was high (100% sensitivity (Sens), 95% specificity (Spec), m...

This paper gives a description of the hitherto unknown larva of Chaetopteryx rugulosa Kolenati 1848 (Trichoptera: Limnephilidae). Information on the morphology of the larva is given, and the most important diagnostic features are figured. In the context of the known European Chaetopterygini and Stenophylacini species, the larva of C. rugulosa can b...

Specific concepts of fluvial ecology are well studied in riverine ecosystems of the temperate zone but poorly investigated in the Afrotropical region. Hence, we examined the longitudinal zonation of fish and adult caddisfly (Trichoptera) assemblages in the endorheic Awash River (1,250 km in length), Ethiopia. We expected that species assemblages ar...

Two factors complicate the ecological status classification of very large rivers in Europe according to the EU Water Framework Directive: First, current assessment methods do not fully consider the specific ecology of very large rivers (such as lateral connectivity and the role of floodplains for ecological status). Second, most of Europe's very la...

Large wood (LW) is an indispensable element in riverine ecosystems, especially in lower river parts. The presence of LW significantly shapes local hydraulics, morphology, the nutrient budget; promotes overall river dynamics; and additionally presents a unique habitat for numerous benthic invertebrate species. Therefore, LW is recognized as valuable...

Climate and land-use change drive a suite of stressors that shape ecosystems and interact to yield complex ecological responses, i.e. additive, antagonistic and synergistic effects. Currently we know little about the spatial scale relevant for the outcome of such interactions and about effect sizes. This knowledge gap needs to be filled to underpin...

This paper describes the previously unknown larva of Plectrocnemia scruposa McLachlan 1880. Information on the morphology of the 5th larval instar is given, and the most important diagnostic features are illustrated. In the context of existing identification keys, P. scruposa keys together with P. brevis McLachlan 1871, P. conspersa (Curtis 1834),...

A new Drusinae species, Drusus katagelastos sp. nov., of the Drusus chapmani Species Complex, is described based on a male and associated larvae. Adult-larval association was achieved through DNA barcoding. The male of the new species differs from that of its congeners in the formation of the intermediate appendages and parameres. Information on th...

The present case study deals with a controlled drawdown beyond the operational level of the Gepatsch reservoir (Austria). Based on the awareness of potential ecological consequences, an advanced set of measures was conducted and an integrative monitoring design was implemented. This pre-and post-event monitoring included measurements regarding the...

ContextLarge near-natural rivers have become rare in Europe, a fact reflected in the high conservation status of many riverine ecosystems. While the Balkan still harbors several intact river corridors, most of these are under pressure from planned hydropower constructions. Unfortunately, there is little information available on the hydromorphodynam...

Horst Aspöck and Raphidia ulrikae in the rock face: Congratulations from 36 zoologists to Univ.-Prof. Dr. Horst Aspöck on the occasion of his 80 th birthday. - Entomologica Austriaca, 27: 421-448. --- Das Opus eines Wissenschaftlers zu umreißen, dessen ungestüme Neugierde, die Natur zu erkunden bereits in der Gymnasialzeit mit 13 Jahren begann und...

Cloeon perkinsi was described from South Africa in 1932 by Barnard. Despite being relatively common in Africa, it was mentioned in the literature quite rarely, and its known distribution to date includes most of sub-Saharan Africa. Material collected recently in Ethiopia, Israel, Saudi Arabia, and Yemen extends its distribution in East Africa, Arab...

The sustainable management of very large rivers is based on the assessment of their environmental condition. However, unlike for smaller rivers, this assessment is yet less advanced due to the specific complexities of very large river systems. In Europe, this is reflected by the lack of an international large river typology classifying these ecosys...

We comparatively examined the role of littoral and deep water sampling methods in assessing macroinvertebrate assemblages and in characterizing longitudinal changes in assemblage structure along >2,500‐km–long course of the Danube River, Europe. The effectiveness of detecting taxa corresponded well with an inshore–offshore gradient in sampling (i.e...

Species of the genus Himalopsyche (Trichoptera, Rhyacophilidae) inhabit alpine to montane environments in Central and East Asia and North America. Diversity of the genus is concentrated primarily in the Himalayas and surrounding mountain ranges. Phylogenetic hypotheses have hitherto been proposed based on morphological data. Here, we present the fi...

The holometabolous insect order Trichoptera (caddisflies) includes more known species than all of the other primarily aquatic orders of insects combined. They are distributed unevenly; with the greatest number and density occurring in the Oriental Biogeographic Region and the smallest in the East Palearctic. Ecosystem services provided by Trichopte...

Effective identification of species using short DNA fragments (DNA barcoding and DNA metabarcoding)requires reliable sequence reference libraries of known taxa. Both taxonomically comprehensive coverage and content quality are important for sufficient accuracy. For aquatic ecosystems in Europe, reliable barcode reference libraries are particularly...

Species reintroductions-the translocation of individuals to areas in which a species has been extirpated with the aim of re-establishing a self-sustaining population-have become a widespread practice in conservation biology. Reintroduction projects have tended to focus on terrestrial vertebrates and, to a lesser extent, fishes. Much less effort has...

The fifth insect camp of the Entomological Society of Austria (ESA) was conducted from April 27 to May 2, 2018. Many of the 39 participants were recognized experts on different arthropod groups. Fifty-seven localities within and nearby the Donau-Auen National Park were investigated, and a total of 1265 invertebrate species identified: 8 Collembola,...

Effective identification of species using short DNA fragments (DNA barcoding and DNA metabarcoding) requires reliable sequence reference libraries of known taxa. Both taxonomically comprehensive coverage and content quality are important for sufficient accuracy. For aquatic ecosystems in Europe, reliable barcode reference libraries are particularly...

Here, we describe the previously unknown larva of Apatania stylata stylata Navás 1916, and add this larva to the dichotomous key to the known European Apatania species. We describe the morphology and most important diagnostic features of the larva and pupa, and support these descriptions with photographic plates. The distribution of Apatania stylat...

The paper provides a short summary of a volume on the natural value of the Vjosa river in Southern Albania. Despite its unique physical and biological environmental features, the riverine landscape is in danger to be critically deteriorated by a series of hydropower dams. The hazards are indicated and the expected violations of international rules...

This paper summarises the results regarding aquatic invertebrates of a few excursions to the Vjosa in Albania, in the vicinity of the villages Poçem und Kutë. It mainly aims to document the status of one of the last free-flowing rivers in Europe, based on its aquatic communities prior to the realisation of the planned building of hydropower plants....

• Studying interactions among co‐evolved invaders might help us in understanding, predicting, and perhaps mitigating the impact of the invading species on the native biota. The factors of spatial niche differentiation were investigated among invasive Ponto‐Caspian peracarids with the aim of revealing how co‐evolved species can coexist with the ‘kil...

Current biomonitoring approaches are widely used but have some limitations. • DNA metabarcoding provides a new complementary tool for biomonitoring. • Metabarcoding allows extending the range of taxa used as bioindicators. • Metabarcoding data could be used to establish molecular metrics and indices. • Future work should standardise procedures and...