• FUNGUP - Role of phytoplankton fungal parasites in biodiversity regulation and food web functioning

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.10.2017 - 01.10.2021

    Funding Agency: FWF

    Project-Leader: Serena Rasconi

    Microparasites are overlooked in pelagic environments as most studies have so far been limited to infectious diseases in macro-organisms and in particular on plants or animals of economical interest, such as fishes and shellfish. Recent molecular surveys highlight a wide variety of eukaryotic parasites in the microbial plankton, mainly recognized as chytrid fungi. Chytrids are adapted to pelagic life as they are characterized by a complex cycle consisting of an infective phase attached to the host from which are produced free swimming zoospores that are released into the environment for new host hunting. By suppressing phytoplankton growth, parasitic chytrids can cause a decrease in primary production. In contrast, by feeding on its algal host, chytrids can convert algal biomass into edible, nutrient-rich spores that are efficiently grazed by zooplankton and filtrator consumers. The current proliferation of harmful and toxic algal species worldwide can constitute a trophic dead end for consumers due to their inadequate quality and potential toxicity. Parasitism can be fostered by such high host abundance and during inedible or nutritionally inadequate algal blooms parasites can constitute an alternative promoting trophic transfer within the planktonic food web, both in terms of organic matter quantity and nutritional quality. Considering that parasites are not only infectious agents, but also occupy various niches in the plankton with more functional and ecological characteristics than previously thought, this research aims to shed light on phytoplankton fungal parasite (chytrids) interactions within the planktonic food web and their role in ecosystem functioning. By combining laboratory experiments with artificial food webs and mathematical modeling, we will investigate how chytrids drive the transfer of the organic matter through the dispersion of their infectious propagules (i.e. spores). The final outcome will be a food web network model including the phytoplankton parasites allowing following trophic trajectories through parasites. We will also calculate ecological indices quantifying the direct and indirect effects of phytoplankton parasites on ecosystem processes such as organic matter recycling and trophic transfer, which are considered to be indicators of stability and resilience of food webs in the context of current global change scenarios.

  • BYTHOALPS: Is Bythotrephes not invasive at home due to prey adaption?

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.09.2017 - 01.09.2020

    Funding Agency: FWF

    Project-Leader: Radka Ptacnikova

    Spreading and establishment of species beyond their native range may have drastic ecological, environmental and socio-economic consequences. While alien species invasions receive attention, detailed knowledge about the species in their native area is often lacking. This is critical since such knowledge would help understanding potential impacts of the species in both native and invaded areas. The apparently lower impacts in the native range are often credited to long time co-evolution, however this assumption is rarely tested. Instead, we suggest that conspicuously invasive species may also have a more significant role than previously considered in their native areas. We propose to investigate the performance of a large voracious predatory cladoceran Bythotrephes longimanus (the spiny water flea) and its impacts on zooplankton populations in a part of its native range, the Austrian Montane lakes, with focus on mechanisms of prey defense adaptations in lakes where the predator is present. We aim to investigate: A) whether and how frequent Bythotrephes may reach abundances that cause significant direct and indirect effects on zooplankton community structure and biodiversity in montane lakes and, B) if difference in prey co-evolution and/or adaption of two common prey species (cladocerans of the Daphnia longispina complex and copepod Eudiaptomus gracilis) with Bythotrephes from lakes with and without presence of Bythotrephes may result in prey behavior changes and increased predator defense. This is important since Bythotrephes is likely an overlooked key species in freshwater ecosystems. Thus, better understanding about its trophic role in the ecosystems is critical for modeling and predictions. The role of Bythotrephes as predator in Montane lakes will be assessed by a combination of several approaches: 1) determination of the abundance of Bythotrephes and its zooplankton prey by combining classical zooplankton net-sampling with new high frequency sonar/ADCP and IR-video profiles for high temporal and spatial resolution data, 2) determination of migration behavior of Bythotrephes and prey by ADCP and IR-video systems, and 3) quantification of feeding in situ using novel molecular analyses of predator gut content. The field studies will be combined with laboratory studies on prey adaptation to Bythotrephes presence, including potential clonal selection of D. longispina. The project leader Dr. Radka Ptacnikova is well experienced in field and experimental work with predatory cladocerans (as shown in 8 publications on this topic). Dr. Jens C Nejstgaard and Prof Marc E Frischer have long experience in zooplankton feeding ecology projects. Nejstgaard also brings new sonar and video approaches to the project. They have both over 50 publications of relevance for the project, including from the highest ranking journals. Prof. Adam Petrusek is expert in predator-prey interactions in Daphnia and provides key expertize on the Daphnia longispina complex taxonomy and clonal structure, with over 40 publications on this topic.

  • sTURN - Does time drive space? Building a mechanistic linkage between spatial and temporal turnover in metacommunities

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.09.2017 - 31.08.2019

    Funding Agency: Sonstige

    Project-Leader: Zsófia Horváth

    Projektlinks:

    Maintenance of biodiversity at the landscape level is fundamentally linked to spatial turnover in composition of local communities (beta diversity). Theory suggests that temporal processes may be one key component sustaining beta diversity. These local temporal dynamics in turn may arise from a number of processes (including stochastic processes like ecological drift, or continuous deterministic species sorting through ongoing environmental changes). At present, we lack empirical evidence about the relative importance of these processes and their contribution to spatial turnover (i.e. beta diversity). The central synthesis aim of our working group is to better link temporal turnover to spatial beta diversity and metacommunity structure, and to understand the role of intrinsic and extrinsic forces in driving this spatio-temporal coupling. We will elucidate the importance of temporal turnover as a key driver of compositional dissimilarity in meta-analyses, and establish general scaling relationships between community turnover in space and time. By doing so, we will differentiate among the importance of alternative processes that drive temporal turnover (priority effects, transient dynamics, drift, and species sorting). Moreover, we will analyse how the coupling between temporal and spatial turnover is linked to essential habitat characteristics (habitat size, productivity), regional species pools and connectivity. The output of the working group will be a synthesis about the importance of key processes regulating diversity in biological communities across space and time. Funding: Synthesis Centre of Biodiversity Sciences (sDiv) in Leipzig; DFG

  • FRAMWAT - Framework for improving water balance and nutrient mitigation by applying small water retention measures

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.07.2017 - 30.06.2020

    Funding Agency: EU

    Project-Leader: Thomas Hein

    Projektlinks:

    The good ecological status of surface water in EU in 2015 has improved by 10 % since 2009. However, there are still major efforts needed in order to achieve a better status of aquatic ecosystems. Various types of measures listed under the name Natural (Small) Water Retention Measures (N(S)WRM) can have significant positive effects on solving environmental problems such as hydrological extremes (floods and droughts), increased fine sediment erosion and deposition, nutrients’ transport and decreased biodiversity. Still a major concern is to understand how different measures might interact and how these measures can be optimized to reach multiple aims and mitigate several management issues. FramWat aims to increase the buffer capacity of the landscape by using the natural (small) water retention measures approach in a systematic way. Since rivers do not observe national boundaries, a collective response and transnational integrated approach is needed to translate the knowledge about N(S)WRM features into river basin management practice. FramWat will provide decision makers with appropriate tools to incorporate N(S)WRM into the next cycle of River Basin Management Plans and offer guidance and raise awareness about the importance of horizontal integration of different planning frameworks.

  • HYDRO-DIVERSITY - The Role of Hydrological Connectivity of Catchment Soils and Streams for the Biodiversity and Functioning of Pre-Alpine Stream Ecosystems

    Biofilm and ecosystem research group (BERG)

    Duration: 01.04.2017 - 31.03.2020

    Funding Agency: ÖAW

    Project-Leader: Jakob Schelker

    Small headwater streams interlink catchment soils with the river network and contribute substantially to CO2 emissions of inland waters. At the same time, recent studies have identified small streams as ‘critical reservoirs’ of microbial diversity, but the origin of this diversity is not well understood. The core objective of the HYDRO-DIVERSITY project it therefore to investigate the dynamic transfer of dissolved organic matter (DOM) and microbial life from catchment soils to streams and to evaluate the impact of these influxes on stream biofilm community composition and biodiversity. The HYDRO-DIVERSITY project will address this task by a unique set of experimental work that will be performed across several soil-stream interfaces located along an elevation gradient within the pre-alpine Oberer Seebach (OSB) catchment in Austria. Overall the HYDRO-DIVERSITY project is set out as an interdisciplinary approach involving the disciplines of hydrology, geography, soil science, chemistry and microbial ecology to understand the origin of biofilms in small streams. This understanding will contribute to gain deeper insights into ecosystem functioning of small streams and their contribution to CO2 evasion. The HYDRO-DIVERSITY project is headed by Jakob Schelker. Collaborators within the project are Dr. Katharina Besemer from the Wassercluster Lunz and em. Prof. Peter Peduzzi from the University of Vienna. The project is funded by the Austrian Acadamy of Sciences from 2017-2020.

  • FLASHMOB: FLuxes Affected by Stream Hydrophytes: Modelling Of Biogeochemistry

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.03.2017 - 29.02.2020

    Funding Agency: FWF

    Project-Leader: Thomas Hein

    The input of organic matter and nutrients to coastal ecosystems is crucial for their trophical state. The quality and quantity of this input is determined by upstream processes in the river system. Though macrophytes can be found within the whole catchment and are affecting the whole ecosystem structure of streams, their role in organic matter and nutrient transformation has obtained less attention. Therefore the main aim of the project is to quantify the effect of macrophytes on downstream C-N-P-Si fluxes in rivers, a key aspect to understand fundamental ecosystem processes and the basis for future management decisions. At present, most studies in this field are simplified, either by detailing only the biogeochemical process or by incorporating only the impact of vegetation on hydraulics. In this study both aspects will be combined in a dynamic coupled model to cover the complex interaction of processes an integrated, numerical model will be developed. A hydrological state-of-the-art 2D model will be coupled with a water quality model (DELWAQ) and an aquatic vegetation growth model. This will be done stepwise, starting with basic biogeochemical processes, adding macrophytes which are affecting flow patterns and biogeochemical transformations, and finally implement sediment/water interactions. With the coupled model different scenarios (with or without aquatic vegetation, changes in environmental conditions due to climate change scenarios) are simulated to test the main hypothesis of the project, that the interactions between macrophytes and the hydrodynamic conditions are determining the transport: transformation ratio of organic matter and nutrients and thus, influencing the overall carbon and nutrient cycles of these river systems. Simulations will be done on sub-catchment scale and cover the vegetation periods of two years. For this study we will select a sub-catchment of the River Danube that has several small vegetated river sections with different plant: water ratios. To set-up the integrated model, a field sampling campaign assessing hydrological and limnochemical parameters, as well as macrophyte development and sediment characteristics will be conducted. These investigations will be complemented with experimental approaches to determine macrophyte growth and decomposition rates of organic matter in the sediment. The findings of the project will expand our knowledge on the role of macrophytes and provides new insights in these complex interactions and how these will be affected by future developments. The model approach combines the expertise of the two involved working groups, WasserCluster Lunz (Thomas Hein) focussing on river floodplain systems and the effects of hydrological connectivity on biogeochemical cycling and aquatic primary production and ECOBE, University of Antwerp (Patrick Meire, Jonas Schoelynck), working on the role of aquatic vegetation in river ecosystem functioning. Partner: University of Antwerp – ECOBE – Patrick Meire. Funding: FWF

  • Organic carbon cycling in streams: Effects of agricultural land use

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.01.2017 - 31.12.2019

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Gabriele Weigelhofer

    Agriculture is the dominant land use form in Lower Austria, covering more than 46 % of the total area. Agriculture delivers significant amounts of dissolved organic matter (DOM) to streams, thereby changing basic processes at the water-sediment interface and affecting the ecological state of the stream ecosystem. The aim of the project is, thus, to investigate the influence of agricultural land use on the quantity and quality of DOM inputs to streams and to clarify the effects of this DOM on the aquatic carbon cycling in stream ecosystems. Our research will be based on both in-situ determinations of DOM quality and stream processes in the Hydrological Open Air Laboratory (HOAL) in Petzenkirchen, a priority area for the FTI strategy of Lower Austria, and on laboratory experiments at the WasserCluster Lunz and the Bundesamt für Wasserwirtschaft (Petzenkirchen). In microlysimeter experiments, we will focus on the effects of different agricultural practices (e.g. fertilization, tillage, liming) on the amount and composition of DOM delivered to fast-draining near-surface flow paths. In the HOAL catchment, we will measure the impact of different flow paths, such as surface runoff, tile drainage and groundwater, on the DOM input during baseflow and stormflow conditions. Via incubation experiments, we will investigate the effects of different DOM sources on the growth and activity of benthic microorganisms, the oxygen consumption in the stream, and the aquatic emission of greenhouse gases. The results will be analyzed with respect to consequences of DOM inputs from agricultural areas for the health and the ecological state of stream ecosystems and will be incorporated into recommendations for a sustainable management of agricultural streams. In addition, the Center for Integrated Sensors Systems at the Danube University Krems will develop a sensor for the in-situ determination of DOM in freshwater to be used in both scientific research and water quality monitoring. At present, DOM analyses in freshwater studies mostly rely on water sample analyses in the laboratory, limiting sampling frequency and affecting data quality. In-field DOM sensors with a high temporal resolution will facilitate the tracking of DOM changes over time, e.g. in response to variations in biotic activities or hydrology, and will, thus, enable a detailed insight into DOM dynamics. In the case of water quality monitoring, DOM sensors could be used to detect organic pollution, such as diesel oil, farm leakage, or sewage inputs, and as early-warning systems of failure in water quality. Funding: Government of Lower Austria (Science call 2015)

  • AQUACOSM - Network of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.01.2017 - 31.12.2020

    Funding Agency: EU

    Project-Leader: Robert Ptacnik

    Projektlinks:

    Lakes, rivers, estuaries and oceans are closely connected. Despite this, aquatic research is still divided in marine and freshwater sciences. Now scientists from 19 leading research institutes and universities and two enterprises from 12 countries across Europe aim to change this and have joined forces in the project “AQUACOSM - Network of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean”. The network will perform the first systematic large-scale experiments in both freshwater and marine ecosystems. The project is coordinated and lead by Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB). "For more than 100 years, inland water and marine research have largely developed in parallel to each other. Now it's time to reunite both", says IGB researcher Jens Nejstgaard, who leads the new EU project. In AQACOSM scientists from both disciplines are building an integrated, international network of experimental infrastructures. Their aim is to significantly improve the quality of experimental data for all types of water. "We want to better coordinate international large-scale experimental research projects, develop good practices together, and open up the freshwater and marine mesocosm research infrastructures for a broader international, interdisciplinary collaboration", says Jens Nejstgaard. Mesocosms are containers in which large volumes (1-1000 m3) of water including the natural organisms is experimentally enclosed and manipulated. In this way effects of individual and combined stress factors can be tested on entire ecosystems over weeks to years. Within the project AQUACOSM researchers will examine how different aquatic ecosystems react to environmental impacts caused by global climate change and the increasing pressure by the growing world population. "The impact of these stress factors can vary widely within different ecosystems and seasons", emphasizes Nejstgaard. Therefore they have to be investigated in different climatic and geographic regions, using comparable mesocosm experiments and measurement methods. AQUACOSM offers the necessary research infrastructures to do experimental research in a range of different European water types, in climatic and geographic zones stretching from the Arctic to the Mediterranean. The experimental infrastructures of the 21 partner institutions include, for example, tank systems and flow channels on land, such as in Lunz am See (Austria) and large free-floating open-ocean facilities such as The Kiel Offshore Mesocosms (KOSMOS). The IGB-LakeLab in Lake Stechlin also set a new benchmark in experimental freshwater research with its unique dimension (24 mesocosms with 1,270 m3 each). Launched in January 2017, the AQUACOSM project runs until December 2020 and is unique in size and approach. It is supported by the European Union H2020-INFRAIA Project No. 731065 with a budget of € 9,999,807.

  • DANUBIUS – PP project: “Preparatory Phase for the Pan-European Research Infrastructure DANUBIUS-RI”

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.12.2016 - 30.11.2019

    Funding Agency: Sonstige

    Project-Leader: Thomas Hein

    DANUBIUS-PP is a three-year project to raise DANUBIUS-RI (International Centre for Advanced Studies on River-Sea Systems) to the legal, financial and technical maturity required for successful implementation and development. 29 partner institutions from 16 European countries are working under the lead of the Romanian research institute GEOECOMAR to develop the structures and processes of the RI in order to ensure that the RI strengthens scientific cooperation and performance in the entire Danube region, from river source to coastal sea. WasserCluster Lunz is one of the partners, contributing substantially to most of the 10 work packages. DANUBIUS-RI will be a pan-European distributed research infrastructure dedicated to interdisciplinary studies of large river–sea systems. It will enable and support research addressing the conflicts between society’s demands, environmental change and environmental protection in river–sea systems worldwide. Read more: http://www.danubius-ri.eu/ Funding: EC H2020 CSA

  • GROW - Dietary pathways of PCBs to top predators in mountain lakes

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.09.2016 - 31.08.2017

    Funding Agency: FWF

    Project-Leader: Martin Kainz

    Die Kenntnis von trophischen Interaktionen in aquatischen Nahrungsnetzen ist für die Evaluierung von Energie- sowie Schafdstoffflüssen notwendig. Ein wichtiges Beispiel ist die Anreicherung von Verunreinigungen entlang der aquatischen Nahrungskette, von Algen bis zu Fischen. Obwohl es bereits Untersuchungen über die Anreicherung von etwa PCBs in Fischen gibt, ist es bis dato unklar, welche Rolle die Nahrungszusammensetzung für den trophischen Transfer dieser Schadstoffe hat. Getrennte Analysen des Fischdarminhalts oder stabile Isotopenanalysen sind oft unzureichend. In diesem Projekt werden wir Energieflüsse aus verschiedenen Nahrungsquellen in Mesokosmen untersuchen. Wir werden state-of-the-art Nahrungs-Biomarker wie stabile Isotopen gemeinsam mit Fettsäurenanalytik und komponenten-spezifischen stabilen Isotopen verwenden, um Nahrungsquellen für Fische und die Nahrungsherkunft von Schadstoffen in Fischen festzustellen. Hierzu werden wir 'mixing models' verwenden, um den relativen Beitrag der benthischen und pelagischen Nahrungsquellen für Fische festzustellen. Diese Methoden werden wir auch an vorhandenen Proben des Nahrungsnetzes des Lunzer Sees anwenden, womit wir die Resultate der Mesokosmenuntersuchungen auch für den See evaluieren können. Wir erwarten, dass die kombinierte Verwendung dieser Analysen unser Verständnis des Nahrungstransfers aus unterschiedlichen Quellen des aquatischen Nahrungsnetzes deutlich erweitern wird und wir dadurch einen Fortschritt für den aquatischen Schadstofftransfer leisten können. Dieses Projekt wird die aktuelle Forschungsarbeit der Doktorandin sowie die Forschungsentwicklung am WasserCluster Lunz über die Auswirkungen der trophischen Strukturen und Energieflüsse auf die Anreicherung von Schadstoffen in Fischen von Bergseen stark unterstützen.

  • WILDE MULDE - Revitalisation of a riverine landscape in Germany

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.09.2016 - 31.07.2017

    Project-Leader: Thomas Hein

    The revitalization of riverine landscapes can impact key ecosystem function and services. The exact effects of revitalization measures on different ecosystem properties are not well known. Thus, in an interdisciplinary project the effect of changes in structural components and hydrological dynamics on biodiversity and biogeochemical cycles in aquatic and terrestrial habitats and associated ecosystem services will be investigated in the riverine landscape of the River Mulde, a tributary of the River Elbe in Germany. Within the revitalization project the following measures will be implemented: removal of river embankments, reconnection of floodplain side-arms and introduction of large woody debris. The aim of the pilot phase of the project is to characterize the status quo and establish predictive models to analyse potential effects of planned measures. The team of WasserCluster Lunz is investigating the current status of inorganic nutrients, namely phosphorus and nitrogen, in different habitats of the riverine landscape, the status of algal communities and thus, to assess the nutrient balance and nutrient retention capacity of the impacted river stretches. Key research questions addressed are how changes in river bank morphology and landscape connectivity will impact nutrient retention behavior, how nutrient uptake and release is affected based on changed physical and microbial properties and how changes in algal development impact the overall retention capacity. Funding: BMUB und BMWF Germany. Coordination of the overall research project: UFZ Leipzig.

  • INTERBIRD - Grenzüberschreitende Koordination der ökologischen Monitoringaktivitäten in den NATURA 2000 Gebieten der Neusiedler-See und Hanság (EU-Projekt Interreg V-A Österreich-Ungarn)

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.07.2016 - 30.06.2020

    Funding Agency: EU

    Project-Leader: Zsófia Horváth

    Projektlinks:

    Astatic soda pans are important natural heritage sites of Europe, which are unique to the Carpathian Basin (eastern Autria, Hungary, northern Serbia). They are listed as priority habitats in the Natura 2000 network of the EU. They are seriously threatened ecosystems, with a habitat loss of 80% in the last 150 years. Seewinkel in eastern Austria with its relatively tiny area hosts 25% of all the remaining soda pans and therefore has a key role in the long-term conservation of these ecosystems. Crustacean invertebrates mean high quality food for waterbirds. Among all aquatic habitats worldwide, soda pans produce the highest crustacean biomass, which makes them particularly important as stopover-sites for migrating birds. While we know that soda pans represent an outstanding resource especially for migrating birds, we are unaware how the food web functions. The project aims at achieving a general understanding of the trophic pathways from primary production up to the birds. Understanding the functioning of an ecosystem is mandatory for its protection and we currently miss crucial knowledge about the basis of a food web and how it contributes to an important ecosystem service (sustaining large flocks of migratory birds). This also has crucial implications for habitat restoration plans.

  • Wasser:KRAFT - Energie aus Wasser – Wasserkraft und Algen: Energiequellen der Zukunft

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.06.2016 - 31.10.2018

    Funding Agency: Bund (Ministerien)

    Project-Leader: Thomas Hein

    Children and teenager from the region of Mostviertel work together with researchers and experts to explore water power. Experts explain how to gain water power using the example of regional water power stations, and ecological consequenzes for streams. Moreover the children learn about microalgae and how to produce engergy out of it. The project is funded by the Austrian Ministry for Transport, Innovation and Technology, it is a cooperation of WasserCluster Lunz, BIOENERGY 2020+, EVN and Hydro-Connect and it is performed in the course of the programm "Talente regional" from the Austrian Research Promotion Agency (FFG).

  • ALPHA-OMEGA - Trophic pathways of omega-3 fatty acids in stream food

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.06.2016 - 31.05.2019

    Funding Agency: FWF

    Project-Leader: Martin Kainz

    Das seit langer Zeit etablierte 'River Continuum Concept' besagt, dass der Oberlauf von Flüssen stark von terrestrischem Eintrag wie Laubfall bestimmt ist. Gleichzeitig stellen die kalten Flussoberläufe auch Lebensräume für Süßwassersalmoniden wie Forellen und Saibling dar, die reich an omega-3 Fettsäuren (n-3 PUFA) sind. Jedoch beinhaltet Laubfall keine n-3 PUFA, die die Salmoniden wie auch Insektenlarven aus physiologischen Gründen benötigen. Es stellt sich daher die konzeptuelle Frage, wie vor allem Fische ihren Bedarf an langkettigen n-3 PUFA in Flussoberläufen decken können. Um diese Frage zu beantworten, verfolgt dieses Forschungsprojekt folgende Ziele; a) räumliche und zeitlich gestaffelte Untersuchung der Nahrungsabhängigkeit von benthischen Invertebraten und Fischen auf die elementare (C und N sowie deren stabilen Isotopen) und molekulare (Lipide und deren Fettsäuren) Futterzusammensetzung entlang voralpiner Flussläufe (Ökosystemuntersuchung), b) experimentelle Forschung über die Rolle von Licht auf die biochemische Zusammensetzung von terrestrischem (Laub) und autochtonem (Algen) Material als Futter für benthische Invertebraten, und, c) Laborversuche an Leberzellen von Fischen (Salmoniden und Cypriniden) aus Flüssen um zu untersuchen, ob und wie Fische aufgrund enzymatischer Eigenleistung kurzkettige n-3 PUFA zu langkettigen n-3 PUFA konvertieren können. Dieses Forschungsprojekt untersucht die Rolle von Futter als Lieferant von Nahrungsqualität (exogene Quelle) und gleichzeitig die Fähigkeit der Konsumenten die Futterqualität biochemisch aufzuwerten ("trophic upgrading"). Diese Untersuchungen werden gemeinsam mit international renommierten Wissenschaftern trophische Zusammenhänge in Nahrungsnetzen von Flüssen evaluieren und die Herkunft von essentiellen langkettigen n-3 PUFA in Fischen feststellen.

  • COMPETITION AND TOP-DOWN CONTROL as potential factors controlling microbial diversity in aquatic networks

    Duration: 01.06.2016 - 31.05.2018

    Project-Leader: Katharina Besemer

    One of the major goals of aquatic ecology is to understand the suite of local and regional processes, which govern community assembly and biodiversity patterns in aquatic networks. In the last years, the significance of microbial diversity for carbon and nutrient cycling in streams, rivers and lakes has progressively been unveiled. A number of studies suggested that species sorting according to environmental conditions constrain microbial diversity in habitats with long retention times such as lakes, while mass effects support microbial diversity in habitats with short water retention times, such as streams. Competitive interactions, dispersal dynamics and interactions with other trophic levels might contribute to microbial diversity patterns; however, experimental evidence for the importance of such mechanisms is missing as yet. The overall objective of the proposed research is therefore to disentangle the mechanisms potentially driving microbial diversity in aquatic ecosystems. Specifically, the following hypotheses will be tested: (i) Competitive interactions govern community assembly in habitats with long water retention times which is reflected in the community’s phylogenetic structure (ii) the diversity of potential bacterivores influences bacterial diversity and (iii) in the absence of dispersal, microbial communities show proliferation of typical freshwater taxa. Using an experimental approach, the diversity of bacteria and small eukaryotes from aquatic habitats differing in retention time under different dispersal regimes will be monitored using microcosms. Data on microbial diversity and community composition will be obtained by Illumina sequencing of the 16S (bacteria) and 18S (eukaryotes) rRNA gene. The phylogenetic structure and the degree of phylogenetic clustering will be used to assess the role of competition between microbial species and potential interactions between different trophic groups. The proposed research is meant to better integrate microbial ecology – itself embedded in a cutting-edge methodological entourage – with ecological theory and will equally contribute to microbial ecology and general aquatic ecology.

  • CHRYSOWEB - The effect of mixotrophic chrysophytes on secondary productivity in pelagic food webs (Marie Curie Individual Fellowship for Csaba Vad)

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.02.2016 - 31.01.2018

    Funding Agency: EU

    Project-Leader: Csaba Vad

    Projektlinks:

    Plankton occupy a key position in aquatic trophic webs, and today, a highly relevant topic lies ahead in assessing its global change-mediated shifts, with implications for the functioning of aquatic systems. Mixotrophic chrysophytes are prevailing elements of phytoplankton in oligo- and mesotrophic lakes. Their contribution is predicted to increase with climate warming, which imply serious consequences for pelagic trophic efficiency and ecosystem services e.g. fish production. However, our current knowledge on the nutritional quality and bottom-up effect of chrysophytes is insufficient. CHRYSOWEB aims to reveal their effects on zooplankton secondary production and diversity in a multi-disciplinary approach, which will significantly contribute to the understanding of carbon flow and nutrient cycling in alpine lakes under global change. Laboratory feeding experiments will be combined with field observations to quantify species-specific responses of relevant zooplankton taxa to chrysophytes. The underlying mechanisms will be biochemically analysed in algae and consumers.

  • EXCARB - Influence of climate extremes on carbon dynamics across the boundaries of aquatic ecosystems

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.02.2015 - 31.12.2017

    Funding Agency: ÖAW

    Project-Leader: Jakob Schelker

    Projektlinks:

    Hydrological extremes are predicted to increase as climate change progresses and we may therefore expect more frequent droughts and floods. The implications of such hydrological extremes on the carbon cycle in inland waters remain poorly understood. The broad objective of EXCARB is to study possible effects of past, present and future hydrological extremes on carbon fluxes at catchment scale and across the boundaries of terrestrial, stream and lake ecosystems. EXCARB will pave the way to construct a predictive model of inland water carbon cycling according to climate projections for the European Alps. Based on historical hydrology records over the last 100 years, EXCARB will identify past hydrological extremes in a pre-alpine catchment, capture signatures of such extremes in lake sediments and establish a present-day carbon balance for a stream-lake continuum in that catchment. EXCARB will also relate these present-day carbon fluxes, including CO2 outgassing, to precipitation and discharge. Finally, a process-based model will encapsulate this ensemble of past and present-day information to help predict the effect of future climate projections on the carbon fluxes in pre-alpine aquatic ecosystems. EXCARB is an interdisciplinary project cutting across ecosystem boundaries that will provide essential knowledge that helps to better place streams and lakes as major players of the global carbon cycle. Funding: Austrian Acedemy of Sciences

  • IMPACTS OF CLIMATE CHANGE and land use on lake ecosystem function and services – a cross-border watercourse level approach in the European Arctic

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.01.2015 - 31.12.2018

    Project-Leader: Martin Kainz

    This project investigates nutrition habits of fish and plankton in different lakes. It is leaded by Dr. Kimmo Kahilainen from the Department of Environmental Sciences of Helsinki University. WasserCluster Lunz contributes the lipid analysis and scientific interpretation of it.

  • GARANT

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.10.2014 - 01.08.2015

    Feeding of new food compositions to chars, constant measurement of zootechnical achievments and the scientific evaluation of this are in the focus of the project GARANT. Funding: Garant – Tiernahrung GmbH.

  • SPARKLING SCIENCE PowerStreams - The self-purification capacity of streams under the pressure of increasing nutrient pollution

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.10.2014 - 31.03.2017

    Funding Agency: Bund (Ministerien)

    Project-Leader: Gabriele Weigelhofer

    Projektlinks:

    The project PowerStreams aims to analyse the effects of nutrient loading and stream channelization on the efficiency and sustainability of the self-purification capacity of streams. We want to identify options for a sustainable management of stream ecosystems by quantifying the interaction of these different human impacts on the stream metabolism. The project is a research-education-cooperation with four partner schools: Francisco Josephinum, BRG Waidhofen/Ybbs, BORG Mistelbach, and HBLFA Raumberg-Gumpenstein. Together with the students, we will measure both the in-stream uptake of dissolved nitrogen and organic carbon and the in-stream production of green-house gases via short-term nutrient addition experiments. The investigations will be carried out in natural as well as degraded stream reaches showing low to high nutrients loads. In laboratory experiments, the students will examine the potential of sediments to produce or retain nutrients and green-house gases under different environmental conditions within the scope of their pre-scientific theses. In addition, we will analyse the effects of long-term additions of dissolved organic carbon on the metabolism and the water quality of streams. Based on our co-operations, we will develop a concept for the support of young academics through research weeks and joint supervisions of pre-scientific theses. Funding: Ministry for science, research, and economy, within the framework of the research-education-programme Sparkling Science.

  • SPATIAL patterns of zooplankton diversity in floodplains (FWF project, Griselda Chaparro in cooperation with Robert Ptacnik)

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.07.2014 - 30.06.2016

    Funding Agency: FWF

    Project-Leader: Thomas Hein

    Understanding the spatial distribution of diversity is a main interest of ecology and its relevance is enhanced under the current scenario of progressive diversity loss. Measures of species diversity are dependent on the spatial scale considered, mainly because environmental factors that affect species composition show different ranges of variation among spatial scales. Despite the relevance of spatial scale is increasingly recognized in biodiversity studies, there is still a lack of understanding on how combined environmental variations at smaller and broader scales influence diversity in a certain region. Riverine floodplains host an exceptional high diversity and the hierarchical arrangement of their environments offers a great opportunity to study how spatial heterogeneity affects patterns of communities composition and diversity at multiple scales. These ecosystems are endangered because of human alterations of the natural flood regime. A comprehensive understanding of diversity distribution will contribute to plan conservation, management and restoration measures. Funding: FWF

  • HECHT - Hechte gefaehrden heimische Fischbestaende

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.01.2014 - 31.12.2015

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Martin Kainz

    Funded by the government of Lower Austria the team of Dr. Martin Kainz investigates how the rising appearance of pike in Lake Lunz influences the food web. Aim is to reduce pike in Lake Lunz.

  • DISPERSE - Role of dispersal for maintenance of diversity in experimental plankton communities

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.01.2014 - 31.12.2016

    Funding Agency: FWF

    Projektlinks:

    An increasing number of observational studies report regional patterns in communities of aquatic protists and zooplankton, pointing at the existence of dispersal limitation in the microscopic world. Moreover, recent studies also show that natural phytoplankton communities exhibit diversity functioning relationships comparable to those known from vascular plants and other higher organisms. The existence of such patterns is in stark contrast to the conventional assumption that communities of microscopic organisms are constantly saturated. Given the importance of diversity for ecosystem functioning, a better understanding on the controls of local and regional factors on plankton diversity is mandatory. Yet, in spite of finding spatial patterns which are in qualitative agreement with metacommunity theory, we are lacking a mechanistic understanding how local and regional factors interactively control diversity in plankton communities. The proposed study aims at studying the role of dispersal for maintenance of diversity in experimental communities. To this end, mesocosms will be connected to a species rich source pool in a gradient design. Diversity and community turnover of bacterio-, phyto-, and zooplankton will be monitored, employing both microscopcic as well as molecular analyses. Measurements of resource use efficiency will be performed for all functional groups. The project will closely collaborate with mathematical ecologists who will use the data for parameterizing a dynamic model on the maintenance of diversity through dispersal.

  • ECATA - Effects of extreme events on carbon cycling along a terrestrial-aquatic continuum at the catchment scale

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.11.2013 - 30.11.2016

    Funding Agency: FWF

    Project-Leader: Thomas Hein

    The Intergovernmental Panel on Climate Change predicts a further global average surface warming - depending on future emission scenarios - in the range of 1.1 to 6.4°C until the end of the 21st century, which may entail dramatic consequences for biophysical and socio-economic systems. As a result of the above-mentioned temperature rise, extreme events, such as high-intensity rainfall events and resulting landslides and debris flows, are expected to increase in both frequency and magnitude. For example, the top 10% of precipitation intensity is predicted to increase by about 95% for each degree Kelvin increase in global mean temperature. These extreme events episodically export large amounts of terrestrial organic carbon (OC) into fluvial ecosystems. This resets vegetation succession and soil formation on land, and exposes terrestrial OC of varying sources, age and composition to physical and (bio)chemical reactions in aquatic ecosystems. Through the former (terrestrial) processes, C is fixed from the atmosphere and re-accumulated in biomass and soils; through the latter (aquatic) processes, the exported OC may partly be respired to the atmosphere, physically or (bio)chemically modified and hence stabilized or destabilized, buried for longer-term storage in deposited sediments, or transported to the ocean. These processes depend on the contribution of different terrestrial OC pools, such as litter and biomass, soil and rock OC, which in turn is controlled by the characteristics of the extreme events. The rates and extents of these processes and their driving forces are still poorly understood and scarcely quantified, but are recently understood to be of major significance at global scales. For an improved assessment of the effects of extreme events on carbon cycling, it is therefore crucial to better understand and quantify the associated terrestrial and aquatic processes. In the ECATA project, we will focus on mountainous catchments in Taiwan, where landslides are frequent and export of terrestrial OC to aquatic ecosystems is high. We will quantify the re-accumulation and stabilization of OC in terrestrial ecosystems, and characterize the processing of exported biomass-, soil-, and rock-derived OC in freshwater ecosystems. The ECATA project will build on extensive experience in monitoring and modeling of landslides and sediment discharge by the Taiwanese partners and combine this with long-standing expertise and cutting-edge techniques to characterize OC in soils and sediments provided by the Austrian partners. Together, this shall yield fundamentally new insights into the fate of OC at the terrestrial – aquatic continuum impacted by extreme events, and provide needed inputs for improved modeling of the effects of extreme events on carbon cycling at regional scales and for better global estimations. Funding: FWF

  • DANCERS - Danube macroregion: Capacity building and Excellence in River Systems (basin, delta and sea)

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.06.2013 - 31.05.2015

    Funding Agency: EU

    Project-Leader: Thomas Hein

    The aim of this project is develop new instruments and tools that will enhance environmental research and promote innovation in Danube Region, including the Danube Delta and the Black Sea. Importantly, the new instruments an tools do not start ab initio but will build on existing projects - covering multiple source of funding (public, private or PPP), whether national, regional or European- which will be identified and clustered. The project will undertake a critical analysis of what has been achieved so far in the region and will build upon results of achievements to-date, to desighn, innovative solutions to strengthen knowledge and busines communities as well as decision makers, specialized in various sectors of integrated management of the Danube-Black Sea macrosystem. The project will be structured on the three main pillars of Research and Innovation (i. Science an Innovation Agenda, ii. Research Infrastructures and iii. Human Capital) - and their relation to the three principal categories of stakeholder: i. Policy and Decision Makers, ii. Business / Industry community and iii. Academia. The spcific objectives of this project are to: 1. critically analyse the acievements in integrated river-delta-sea management in the Danube Region, 2. understand links between the achievements, deliverables and results of the work performed. 3. Define aset of instruments to enhance environmental research and innovation in Danube Region. The ultimate deliverable will be a toolbox of instruments which will yield 1. a strategic research agenda, 2. a concept and detailed plan of the distributed research infrastructure - bot for the Danube-Black Sea Macrosystem and 3. Proposals for an integrated educational program to be implemented at a regional level in the immediate future, with the full cooperation of partner from Danube-Black Sea Macrosystem. Funding: EU FP7; More Information: www.dancers-fp7.eu

  • INTERFACES - Ecohydrological interfaces as critical hotspots for transformations of ecosystem exchange fluxes (Marie Curie Fellowship, Kyle Boodoo)

    Biofilm and ecosystem research group (BERG)

    Duration: 01.02.2013 - 31.12.2017

    Funding Agency: EU

    Project-Leader: Jakob Schelker

    Gravel bars impact the hydrology and biogeochemistry of streams and rivers. Gravel bars force oxygen rich stream water into the river bed and floodplain where it mixes with nutrient and carbon rich groundwater in a natural bio-reactor “the hyporheic zone”. This is a dynamic mixing zone for these two waters. In the hyporheic zone, diverse microbial communities and fauna exist and a variety of chemical reactions occur, producing CO2 and other metabolic products. This “hyporheic” water returns to the stream after some time, biologically and chemically different from both its constituent components. INTERFACES is a Marie Curie research project (2013-2017) funded by the European Union’s FP7 programme involving 11 PhD and 4 post-doctorate researchers from over 12 institutions and 7 countries. The researchers utilize interdisciplinary methods to investigate the roles and processes occurring at important environmental system boundaries (interfaces) such as the “hyporheic zone”. The INTERFACES project work in Austria, based at University of Vienna/Wasser Cluster Lunz, is co-ordinated and supervised by Prof. Tom Battin and new BERG group leader Dr. Jakob Schelker. PhD researcher Kyle Boodoo (AG BERG) investigates the effect of in-stream gravel bars on carbon cycling, stream ecosystem metabolism and ultimately the potential for enhanced CO2 releases to the atmosphere in the Oberer Seebach (Lunz am See). Funding: EU, FP7

  • PRO AQUA, PRO TERRA

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.01.2013 - 31.03.2015

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Thomas Hein

    Streams and groundwater in agricultural landscapes are usually heavily loaded with nitrate. Denitrifying bio-reactors have been used to reduce nitrate loads in drainage water by enhancing denitrification through the supply of organic matter in an oxygen-reduced environment. So far, few studies have concentrated on the environmental soundness and sustainability of this approach. In the project, we investigate the effects of denitrifying bio-reactors on the water quality of nutrient-enriched water. Beside the efficiency in nitrate reduction, we focus on the total nutrient budget of the treated water (e.g. NH4, PO4, or DOC output) as well as on the potential production of greenhouse gases (e.g. N2O, CH4). In lab experiments, we test the optimal conditions for denitrifying bio-reactors to maximize nitrate reduction and minimize “side-effects” harmful to the environment. Funding: Land NÖ

  • BIOERODS (Marie Curie Fellowhip, William Hunter)

    Biofilm and ecosystem research group (BERG)

    Duration: 01.01.2013 - 31.12.2015

    Funding Agency: EU

    Project-Leader: Tom J. Battin

    Inland waterways are an important component of the global carbon cycle, receiving an annual carbon input of ~ 4.8 Pg of carbon per year. Of this approximately 0.6 Pg is buried, entering the lithosphere, whilst 3.3 Pg is recycled through aquatic food webs. These numbers highlight the global importance of streams, rivers lakes and other inland waters but provide little detail regarding the dynamics of organic matter burial and remineralisation. A poorly defined aspect is the relationship between organic matter burial and remineralisation of organo-mineral complexes. Organo-mineral particles form by adsorption of dissolved organic matter to freshly-eroded mineral surfaces, and are thought to greatly control the fluxes of particulate organic carbon at the watershed scale. The unique physico-chemical properties of these particles may enhance their deposition onto and subsequent burial into the sediments of inland waters. However, the metabolic fate of these particles at the water-streambed interface remains poorly studied. Particle deposition at the streambed is enhanced by benthic microbial biofilms. As such, understanding the potential role of organo-mineral complexes in the preservation and burial of organic matter, requires investigation of the interactions with biofilms. Bio-ERODS aims to experimentally investigate biophysical mechanisms driving biofilm-particle interactions and mechanisms that potentially alter the organo-mineral complexation and thus contributing to stream biogeochemistry. Bio-ERODS will thus elucidate, at the fine scale, fundamental mechanisms of the controls on carbon fluxes in streams and rivers.

  • LIMNOTIP - Biodiversität und Tipping Points: Zukunft für Binnengewässer

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.12.2012 - 30.11.2015

    Funding Agency: FWF

    Project-Leader: Martin Kainz

    The accelerating loss of global biodiversity has affected species in all biomes and ecosystem types. Eutrophication is and continues to be a major and severe environmental threat both within and outside Europe, which causes abrupt regime shifts, i.e. systems that reach “tipping points” and change from clear-water states to turbid conditions with dense algal blooms. Reaching such tipping points generally results in a dramatic decline in biodiversity. Using algae-zooplankton feeding experiments, we investigate how changes in algal biodiversity along a productivity/temperature gradient affect the amount of essential dietary nutrients (including lipids and their omega-3 fatty acids) available for higher trophic levels. We hypothesize that, a) algal biodiversity increases with increasing phosphorus (P; limiting nutrient) concentrations and temperature, but decreases once P concentrations and temperature keep increasing (identification of P- and temperature-induced tipping points), and, b) increasing algal biodiversity initially increases the amount of omega-3 fatty acids per unit biomass, but levels off with further biodiversity increase. These tests help enable us to assess the 'tipping point' at which the biochemical, dietary quality of algal biodiversity decreases. As a consequence, we predict that reduced algal biodiversity will lead to lower nutritional values of e.g. crustaceans, which constitute major dietary energy for fish. Hence, changes in algal biodiversity due to climate change may affect processes determining the resilience and induce tipping points for biodiversity and social-ecological systems.

  • FISK - Partial replacement of marine fish by pumpkin seed press cake in fish feeds for freshwater aquaculture - a test on Salvelinus alpinus

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.07.2012 - 01.07.2014

    Funding Agency: Bund (Ministerien)

    Project-Leader: Martin Kainz

    Freshwater aquaculture feeds still rely heavily on additions of marine fish, although it is known that marine fish stock keeps declining worldwide and the price of marine fish oil continues to increase dramatically. The aim of this research project is to evaluate how the use of sustainable, locally produced fish feeds affect the somatic development and lipid quality (in particular omega-3 fatty acids) of arctic charr (Salvelinus alpinus) in aquaculture. This research will be conducted in a series of aquaculture tanks at two temperatures and different feed compositions, using pumpkin seed press cake as partial surrogate of marine fish. We test the hypothesis that the somatic development and lipid composition of arctic charr is independent of diet quality because all fish feeds contain, a) sufficient dietary energy to support somatic growth and, b) enough omega-3 fatty acids that allow arctic char to convert shorter chains to longer fatty acid chains (ability of char to trophically upgrade its diet). In collaboration with GARANT (only Austrian producer of fish feeds), veterinary medicine, international molecular lipid research (University of Stirling, Scotland), and testing fish for human consumption (University of Natural Resources and Life Sciences, Vienna), we strive for basic and applied scientific findings for, a) health, somatic development and biochemical lipid composition of alpine char, b) applicability of pumpkin seed press cake as partial replacement of marine fish for freshwater aquaculture fish feeds, and, c) optical and sensory quality of farm raised arctic char for human consumption. Funding: BMLFUW

  • PHYTO- UND ZOOPLANKTONDIVERSITAET in (Sub-)Alpinen Bergseen entlang eines Hoehengradienten

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.01.2012 - 31.12.2013

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Robert Ptacnik

    Projektlinks:

    Funding: Land NÖ

  • DIVERSITAET der Planktongemeinschaft in Salzlacken

    Aquatic biodiversity accross temporal and spatial scales (AQUASCALE)

    Duration: 01.01.2012 - 31.12.2014

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Robert Ptacnik

    Working group AQUASCALE investigates biodiversity of zooplankton communities in soda pans of national park Seewinkel (Burgenland, Austria). Funding: Land NÖ

  • PILOT PROJECT Bad Deutsch Altenburg

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.01.2012 - 31.12.2024

    Funding Agency: Bund (Ministerien)

    Project-Leader: Thomas Hein

    Projektlinks:

    Within the frame of the management concept “Integrated River Engineering Project” (IREP) for the Danube east of Vienna of the Austrian Federal Waterway Agency (viadonau), the Pilot Project Bad Deutsch-Altenburg (PP BDA) was developed and is the sixth pilot project in the Alluvial Zone National Park. This project mainly addresses improvements of the morphology and the spatial and temporal development of flow reduced areas in bank zones and permanently reconnected backwater systems. The restoration project is carried out on a river section of almost 3 km near Bad Deutsch Altenburg (river km 1887.5 – 1884.5) and the set of measures combined are: measures aiming at granulometric river bed improvement, innovative low water regulation, riverbank renaturation and waterway linkage (connection of the Johler side arm). The engineering measures are monitored in detail, analysing the effects of the measures and thus, providing inputs for the adaptive planning process. The monitoring program aims to answer the question what the effects of the different measures on specific organisms, processes and environmental conditions at different time scales are. It includes various abiotic and biotic work packages. The monitoring is run by a team of experts covering engineering, hydrological, morphological, landscape, biogeochemical and ecological aspects (WasserCluster Lunz, University of Natural Resources and Life Sciences Vienna, Technical University Vienna, University Vienna and 3 private companies).WCL coordinates the biotic monitoring programme and is studying the development of the river section in the fields of ecological functions and processes, habitat diversity and benthic macro invertebrates. Funding: Austrian Federal Ministry of Transport, Innovation and Technology and EU (Trans-European Networks)

  • PRIME - Stream biofilms: a prime site for priming

    Biofilm and ecosystem research group (BERG)

    Duration: 01.07.2011 - 31.07.2014

    Funding Agency: FWF

    Project-Leader: Tom J. Battin

    Priming occurs when the presence of labile organic carbon enhanced the metabolism of recalcitrant organic carbon. Mechanisms of priming and its implications for carbon cycle in increasingly studied and understood in soils but not in aquatic ecosystems. We propose to systematically and rigorously study priming in benthic biofilms in streams. We postulate that the close spatial proximity of algae, and their labile exudates, with microbial heterotrophy enables priming of putative recalcitrant terrigenous organic carbon in streams. Thus we postulate benthic biofilms as a prime site for priming and suggest a series of experiments to test this. Microcosms with biofilms and labeled (13C) recalcitrant organic carbon will serve to quantify priming and, and a combined genomic, transcriptomic and proteomic approach will unravel possible mechanisms, including shifts in community structure and enzymatic activities. Next, streamside flumes will serve to assess the implications of priming at the level of quasi-natural systems. Finally, the relevance for priming will be studied in selected stream reaches in Europe and the USA. The proposed research may contribute to better understand the net heterotrophy in numerous headwater streams and their contribution to global carbon cycling. Funding: FWF

  • QUEENSLAND - Assessment of the needs of the waterholes and floodplain of the Condamine and Balonne and Border Rivers

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.07.2011 - 31.03.2012

    Project-Leader: Martin Kainz

    The aim of the project QUEENSLAND is to establish collaborative research to determine interactions between flow regime and the quality of waterholes as refuges for fish and other aquatic biota and how this influences the function of waterhole refuges. In dryland rivers, the quality of waterhole refuges in terms of food availability and food quality impacts on their ability to maintain healthy fish populations during periods of isolation. Quality is likely to influence both survival and reproductive fitness of resident fish, which in turn will determine the resistance and resilience capacity of fish populations to disturbance from drought in these rivers. Despite this important role of waterhole quality in maintaining fish populations in dryland systems, very little specific detail is known about either fish responses to changes in food availability and quality or how river flow regimes influence the availability and quality of food resources in these waterholes. It is important that we develop a more detailed understanding of these relationships in order to enable us to better manage river flows to sustain healthy fish populations. Such an understanding will permit us to make predictions concerning the ecological impacts of modified flow regimes and thus allow improvements to be made to the provisions of water resource plans. To implement the project we will select 5 waterholes in the Balonne system for repeated temporal study on 4 occasions. The outcome of this work will be to improve understanding of the ecological response of waterholes to changes in water flows in order to inform the development of environmental flow requirements for ecological values and assets dependent upon waterholes. This will allow improvement to be made to the provisions of the relevant water resource plans.

  • ALGFLO: Algal dynamics in Floodplains

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.03.2011 - 31.08.2015

    Funding Agency: FWF

    Project-Leader: Thomas Hein

    According to ecological theory, the frequency of disturbance strongly affects the diversity of biological communities. Whether such a disturbance results in an increase or decrease in the diversity of a community also depends on the productivity and the resource supply rate. Thus, in environments with low nutrient supply, the same disturbance may have opposing effects on communities as compared to environments with high nutrient supply. This important interaction is, however, seldom considered in investigations of disturbance effects on plankton and benthic communities. To elucidate this interaction between disturbance, productivity and diversity, floodplain water bodies are the particularly suited ones. A strong relationship between disturbance and the development and structure of algal communities can be found there. The particular features in these water bodies also enable us to address the interactions between benthic and planktonic communities with regard to the above described interplay. Hydrological retention in floodplain water bodies is associated with lower flows, increased transparency of the water column, and lower nutrient inputs from the main channel. Disturbance and gradients of productivity and resource supply are given in an appropriate range to test the relationships between diversity, productivity and physical disturbance. Thus, the impact of environmental disturbances on productivity - diversity relationships are research questions which can be addressed excellently in these types of ecosystems. Our research program will deal with productivity-diversity relationships, effects of physical disturbances on phytoplankton and phytobenthos communities, and with phytoplankton-phytobenthos interactions at variable environmental conditions. To investigate our research questions we will perform a field survey to test if a relation between productivity and species (functional) richness of natural communities exists. We will evaluate species diversity along a major environmental gradient, incorporating variations in productivity and disturbance. By focusing on phytoplankton, phytobenthos, and their interaction we will cover important primary producers in these dynamic aquatic systems. In a second step we will perform two large field experiments with natural aquatic communities under defined conditions. We will investigate the responses of phytoplankton, phytobenthos, ciliate, and zooplankton biomass and diversity parameters in a combined mesocosm approach. We will investigate the key factors affecting diversity, biomass stoichiometry, and interaction of natural phytoplankton and phytobenthos communities after a flood event: light (turbidity) and nutrients (primarily phosphorus). Additionally, we will perform laboratory experiments to test the concurrence-interactions between phytoplankton and phytobenthos under different environmental parameters in detail. The project will advance existing knowledge on the response of natural plankton communities in highly dynamic ecosystems. It will help to develop a more detailed understanding about the coupling between diversity and productivity in floodplain ecosystems and how physical disturbances shape algal communities and their interaction in aquatic ecosystems. Funding: FWF

  • KOORDINATION LOBAU - Gewaesservernetzung (Neue) Donau - Untere Lobau (Nationalpark Donau-Auen)

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.01.2011 - 31.12.2014

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Thomas Hein

    The aim of the project is to examine the feasibility of a re-connection of the Lower Lobau to the Danube River with a flow of 20 m / s to 80 m³ / s, taking into account all the framework requirements. Therefore, a calibrated mass transfer models for both groundwater and surface waters as well as a sediment model for the entire Lower Lobau will be developed. Furthermore, detailed examinations of drinking-water-related quality parameters will be conducted in the Danube and in selected locations in the Lower Lobau. From an ecological point of view, limnological processes, important nature conservation-related groups (FFH-species), and biological quality elements according to the EU Water Framework Directive will be monitored and analysed and habitat models for selected species groups will be generated. Funding: EU, Stadt Wien, Lebensministerium

  • PRIMA (Marie Curie Fellowship, Mia Bengtsson)

    Biofilm and ecosystem research group (BERG)

    Duration: 01.01.2011 - 31.12.2014

    Funding Agency: EU

    Project-Leader: Tom J. Battin

  • INTERACT

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.01.2011 - 31.12.2013

    Project-Leader: Martin Kainz

  • LIPTEMP - Temperature and diet effects on Daphnia lipids and fitness

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.01.2010 - 31.12.2014

    Project-Leader: Martin Kainz

    Aquatic primary producers synthesize and subsequently supply dietary essential lipids and fatty acids required for somatic development, reproduction, and eventually survival of consumers. Poikilotherms, including algae, zooplankton, and fish, have a vital physiological requirement for polyunsaturated membrane lipids to keep their membranes fluid, to stay active and eventually survive at low water temperatures. Although we could lately increase our understanding of taxa-specific fatty acid retention patterns, little is still known about, a) the ability of algae and zooplankton to adapt their membrane lipid composition at different temperatures, b) how temperature and algal diet affect somatic growth condition, reproduction, and survival of zooplankton. We propose a series of laboratory experiments to study effects of water temperatures on lipid composition of organisms at the aquatic plant-animal interface and on life-history traits of the cornerstone freshwater herbivore Daphnia. In the first step, the effect of temperature on lipid composition of different primary producers (cryptophyta, bacillariophyta, chlorophyta) will be tested. Second, laboratory feeding experiments will be used to investigate temperature-dependent regulation of the fatty acid composition of the two main lipid classes (membrane and storage lipids) in Daphnia. Moreover, we test the ability of daphnids to respond adaptively to different temperatures by regulation of enzymes enabling them to form different phospholipids to offset a cold-induced rigidification of cell membranes ('homeoviscous adaptation'). Subsequently, this knowledge will be related to variation of somatic growth rates, reproductive success, and survival of Daphnia at different temperatures. This research project links water temperature (external factor) with physiological adaptation strategies (endogenous regulation) at the base of the aquatic food chain. This proposal will employ state-of-the-art methods, including cell membrane-specific fatty acids analysis, gene expression as well as nucleic acids analysis (for indicating somatic growth conditions). Results of this proposal will contribute to a more detailed and highly required understanding of nutrient and biomass dynamics at the base of the aquatic food chain, and will provide critical information about biochemical quality of dietary lipid supply to higher trophic levels under different water temperature scenarios. Funding: FWF

  • ARCARNET - The architecture of carbon fluxes in fluvial networks (START-Project)

    Biofilm and ecosystem research group (BERG)

    Duration: 01.06.2009 - 31.12.2015

    Funding Agency: FWF

    Project-Leader: Tom J. Battin

    Streams and rivers have long been considered as "pipelines" in the landscape that transport organic carbon (C) from the continents to the oceans. Recent studies have dramatically changed this perception, showing that aquatic ecosystems emit significant amounts of CO2 to the atmosphere, and that terrestrial C largely fuels the net heterotrophy in these ecosystems. Obviously, these observations raise the question: how can organic C that was initially stored in soils over extended periods become oxidized in streams and rivers despite the relatively short residence time in these ecosystems. ARCARNET will address this central question using an interdisciplinary approach to biodiversity and ecosystem functioning that merges microbial ecology and biogeochemistry with geophysics. Novel methods such as metabolomics and metagenomics will be rooted in advanced network and ecological theory. Microbial biofilms and their counterparts, the suspended aggregates, are major drivers of carbon cycling in streams and large rivers. First, we will study the architecture and composition of these communities and relate them to the geophysical setting in fluvial networks. We will test our hypothesis that biofilms and aggregates are analogous microbial lifestyles adapted to the geophysical setting to enhance their metabolic capacity. Using experimental metagenomics, we will identify populations involved in the metabolism of key organic compounds of terrestrial origin. We will also test the effect of algal priming and photooxidation by UV-radiation on the degradation of putatively recalcitrant compounds. New ultra-high resolution metabolomics will contribute to unravel some of the mechanisms underlying priming and photooxidation. In a comparative approach, will then study whole-ecosystem metabolism in and CO2 outgassing from various ecosystems in Alpine, tropical and Arctic networks. The carbon cycle in these biomes is predicted to be particularly prone to global warming. This ecosystem-level information, coupled with our mechanistic fine-scale understanding of processes, will serve to test fluvial networks as metaecosystems and their performance to oxidize terrestrial organic carbon. Funding: FWF

  • LITERATURE STUDY on the effects of salination on benthic invertebrates caused by road drainage run off

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.01.2009 - 31.12.2009

    Project-Leader: Thomas Hein

    Salt is used on Austrian roads in winters to keep them ice-and free and snow free under specific conditions. The effects of chloride placement in rivers on the biota are hardly known. A literature study on the effects of salination on benthic invertebrates caused by road drainage run off will be conducted. Existing chemical and biological data from rivers and streams in Lower Austria will be evaluated addtionally. As project output of the first phase, a paper will be produced to serve as information and guideline for authorities working in this field.

  • OSTARRICHI FISCH - Identification of essential dietary constituents versus potentially toxic compounds in aquatic food webs

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.01.2009 - 01.09.2011

    Project-Leader: Martin Kainz

  • WETWIN - Tools for supporting the sustainable management of freshwater wetland with special regards to their roles in drinking water supply, sanitation, livelihood and ecological restoration

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.11.2008 - 01.12.2011

    Project-Leader: Thomas Hein

    Wetlands provide multiple services for the biosphere of our planet as well as for the human society: They are able to improve drinking water quality, to purify nutrient-rich river water, to protect human settlements from floods and to supply agricultural land with nutrients. In addition to this, such ecosystems increase the overall stability of the earth’s biosphere, acting as buffers against global change factors such as increasing temperature, droughts, floods and other extreme events. Within the past 150 years, wetlands have been largely threatened and degraded due to human activities like flood protection measures, intensive agriculture or the building of electric power plants and human settlements. Therefore, it is of utmost importance to preserve and ameliorate the ecological state of the remaining wetlands. Despite their protection by international contracts like the Ramsar convention, sustainable and wise management of these key ecosystems is still rare. The project WETwin, supported by the 7th Framework Programme (FP7) of the European Commission, is based on the “ecosystem services approach” defined in the “Millennium Ecosystem Assessment” of the United Nations Development Programme (UNDP) as well as on the UNESCO-HELP approach. WETwin aims at developing a broadly applicable toolbox which allows wetland managers to find sustainable, realistic and appropriate management options and to decide for the best compromise solution. Thereby, the needs of the local population (for example safe drinking water or maintenance of agricultural land) are considered as well as the requirements of a healthy ecosystem itself. Special emphasis is placed on the interactions between river basin and wetland scale on the one hand and on global (climate) change aspects on the other hand. The toolbox is built up in a modular way and may contain software tools (simulation- and decision support tools) as well as questionnaires for local inhabitants and decision makers and expert judgement systems. Six wetlands on three continents (Europe, Africa, South America) differing in size and character, are taken as examples for finding such optimal management strategies. In this way, the project WETwin also aims at enhancing north-south and south-south cooperation. Within this project, WasserKluster Lunz collaborates with the following international partner institutions: VITUKI, Budapest; Soresma, Belgium; Potsdam Institute for Climate Impact Research (PIK); UNESCO-IHE, Institute for Water Education; NGO Wetlands International; NWSC, Uganda; IWMI, South Africa; ESPOL, Ecuador.

  • BAGGERSEEN - Impacts of gravel lakes on the surface and groundwater quality Impacts of gravel lakes on the surface and groundwater quality

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.06.2008 - 31.05.2011

    Funding Agency: Land (inkl. deren Stiftungen und Einrichtungen)

    Project-Leader: Martin Kainz

    Sand and gravel are essential raw materials. Due to the limited quantity of these natural resources a sustainable excavation is of high economic relevance. However in Austria, 20 ha of potential resource areas are lost daily due to settlement and road construction. ?The average annual production of sand and gravel from major pore aquifers, e.g. in Lower Austria, is estimated at nine million cubic meters. The extraction process is either by a "dry" or a "wet" excavation. In wet excavations the material is obtained from underneath the groundwater or at the fluctuation level and results in a gravel pond. This causes both adverse and beneficial effects to the ground-water and surface-water systems (e.g., denitrification, heavy metal mobilization, input of pollutants). The aim of this project is to investigate the (possible negative) influence of gravel ponds on the groundwater quality. Knowledge of this issue will help minimize the conflict between a secure water supply and a sustainable excavation of sand and gravel resources. The estimated influence of gravel ponds on groundwater quality must address the hydrological, biological and biochemical processes. This requires an understanding of the mass balances composing the gravel pond/groundwater system. To obtain a holistic understanding of the system, several lakes in Lower Austria, Upper Austria and Styria will be selected to identify and analyze processes affecting the groundwater quality.? Factors influencing the groundwater will be investigated in an interdisciplinary approach by Prof. Dr. Thilo Hofmann from the Department of Environmental Geosciences (University of Vienna), responsible for the hydrological and hydrochemistry parameters and Prof. Dr. Tom J. Battin and Dr. Martin Kainz from Department of Limnology and the WasserKluster Lunz, respectively, who will address the biological conditions and effects on the ecosystem. Funding: States of Lower Austria, Upper Austria, Styria;Forum Rohstoffe

  • KARPFEN - Diet effects on fatty acids and mercury in carp

    Aquatic lipid and ecotoxicology research group (LIPTOX)

    Duration: 01.04.2008 - 30.04.2011

    Funding Agency: FWF

    Project-Leader: Martin Kainz

    The objective of this translational research proposal is to study effects of essential (polyunsaturated fatty acids, PUFA) and potentially toxic (methyl mercury, MeHg) fish diet composition on PUFA and MeHg concentrations, and somatic growth condition of farm-raised common carp (Cyprinus carpio), a frequently consumed diet fish in Austria. This proposal bridges scientific ecological, ecotoxicological, and nutrition questions. Based on dietary supply of various biochemical fish feed compositions, the following hypotheses test that, A) increased biochemical quality of fish diet, as measured by omega-3 and -6 PUFA, results in increased PUFA concentrations of C. carpio (effect of selective essential nutrient retention); and, B) increased concentrations of the contaminant MeHg cause increased MeHg concentrations in C. carpio (effect of bioaccumulation). Moreover, it will be examined how higher dietary PUFA concentrations enhance somatic growth of C. carpio. For this effect it is expected that high RNA:DNA ratios relate to higher somatic growth condition, as RNA content is connected with protein synthesis rate and DNA content with cellular multiplication, which provide a general measure of the condition of C. carpio. Results of this project will thus further our understanding on how diet composition improves fish quality. These findings are directly applicable for fish feed producers and fish farmers to further their understanding on how to increase highly desirable PUFA concentrations and to decrease MeHg bioaccumulation in C. carpio. Dietary benefit-risk assessments for PUFA-MeHg profiles will finally lay the groundwork for diet recommendations (desired for preventive medicine). The basic and applicable scientific outcome of this proposal will be greatly enhanced through close collaboration between a fish feed producer (GARANT Austria), the long-standing knowledge of fish farming (Teichwirtschaft T. Kainz; not related to the proposer!), and the scientific expertise of aquatic lipid ecology and ecotoxicology of the principal investigator. Funding: FWF

  • PROFOR: Development of a guideline for heavily impacted low order streams in the Weinviertel and in South Moravia for a sustainable improvement of the water quality ETC-Project ProFor Weinviertel:Process-orientated research about the self-purification of small, heavily impacted streams in Weinviertel (A)

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.12.2007 - 31.12.2013

    Funding Agency: EU

    Project-Leader: Thomas Hein

    The aim of the project was the development of a guideline for heavily impacted agricultural low-order streams which contains management measures for a sustainable improvement of the water and sediment quality (with a special focus on nutrients). The guideline is based on investigations about land use, hydromorphology, as well as water, sediment, and soil quality of case studies in the project area. We estimated the potential for improvement via experiments regarding the self-purification capacity of the streams and the nutrient uptake and release by the sediments and determined influencing factors. Funding: EU, Land NÖ, Lebensministerium

  • CANFLOOD

    Biogeochemical functions: research and management at multiple scales research group (BIOFRAMES)

    Duration: 01.07.2007 - 31.03.2011

    Funding Agency: FWF

    Project-Leader: Thomas Hein

    River ecosystems play a key role in the transport and transformation of carbon and nutrients. While material is being transported downstream, organic matter is produced and degraded. This matter carries the fingerprint of human activities along its entire course. Microbial community features such as composition and activity are the major biotic component in all processes, especially in nitrogen cycling. Within the riverine landscape these processes are strongly associated with the availability of retention zones such as floodplain, riparian and instream zones. The processes related to nitrogen and organic matter cycling are basically controlled by the hydromorphology. Thus, at the landscape scale, three fundamental principles regulate the cycling and transfer of carbon and nitrogen in river ecosystems: i) The mode of carbon and nitrogen delivery affects ecosystem functioning - connectivity patterns; ii) Increasing contact between water and soil or sediment increases nitrogen retention and processing - geomorphology; iii) Floods and droughts are natural events that strongly influence pathways of carbon and nitrogen cycling. These three principles can be strongly affected either by natural disturbances or anthropogenic impacts, which involve altered water regimes or a change in the geomorphologic setting of the river valley. An altered natural water regime will affect the biogeochemistry of riparian and instream zones as well as their ability to cycle and mitigate nutrient fluxes originating from upstream and upslope. This calls for a more integrated approach including restoration of landscape dynamics and key ecosystem processes such as carbon and nutrient retention. In this context the objectives of our project are i) to understand the consequences of changes in flow regimes on the functioning of river ecosystems and, more specifically, on their nitrogen cycling capacity, and ii) to accurately estimate the rates of these biogeochemical processes under hydrological changes. The following 3 hypotheses based on the 3 above-mentioned fundamental principles are the methodological approach to investigate the regulation of nitrogen and carbon cycling and transfer at the sediment/water interface in retention areas of river ecosystems: H1: The hydromorphic structures of retention areas affect the nitrogen cycling: High surface water connectivity levels and high sediment to water ratios in retention areas increase potential denitrification rates and the N2/N20 ratio. H2: The mode of organic carbon supply to retention areas controls denitrification potential because carbon availability directly affects microbial nitrogen processing at the sediment surface H3: Past water regime patterns control the resistance and the resilience of the nutrient cycling processes to restoration and rehabilitation measures because they have shaped the current geomorphological setting of retention areas at the habitat and at the reach scale. Funding: FWF