Sessions

Aquatic viruses are abundant, and they are considered key players in structuring microbial communities and regulating phytoplankton. Little is, however, known about the diversity of viruses interacting with the different trophic levels within lake communities and to what extent community and biogeochemical cycling are affected by virus infections. The session aims to discuss methods to sample, detect and identify viruses, dynamics of host-virus systems and consequences for community/ecosystem dynamics and functioning.

Session chair: Ana del Arco, Lutz Becks

Vortragsspache: Englisch

Symbiotic relationships refer to the close association of two or more different species living physically together and comprise parasitic, commensalistic, mutualistic, competitive, and predator-prey interactions. Symbiotic interactions are common across all ecosystems and can determine ecosystem dynamics, functioning and persistence. The form of symbiosis is defined by the costs and benefits of the interaction for both partners, the relative duration of the association and the dependence of the partners on each other. All these factors in turn depend on the environment and (co)evolutionary history. Therefore, rather than referring to a single specific relationship, symbiosis is now recognized as a continuum of species interactions, where the form of the interaction may change with the environment. By affecting the organisms’ fitness, changes of symbiotic interactions potentially alter population dynamics and community composition. However, many symbiotic interactions, their costs and benefits and particularly potential shifts of such interactions in dependence of the biotic and abiotic environment are still poorly understood and hardly integrated into the broad theories of community structure and functioning. In this session we welcome observational, experimental and modelling studies that provide information and improve our understanding of symbiotic interactions in aquatic systems, their costs and benefits, and how feedbacks and controls operate. In particular, we welcome contributions addressing how the type of symbiotic interactions shift along environmental gradients and what consequences can be expected for ecosystem functioning, including food web structure and dynamics, biodiversity change, altered biogeochemical processes, and ecological shifts across temporal and spatial scales.

Session chairs: Sabine Flöder, Birte Matthiessen, Stefanie Moorthi

Vortragsspache: Englisch

Aquatic ecosystems are under severe pressure by several anthropogenic stressors affecting ecosystem state, development, and function. Trophic change, climate warming, changes in hydrology, but also the invasion by neobiota are consequences of human activities that have caused substantial and complex changes in aquatic ecosystems. The mechanisms leading to different patterns of ecosystem response, e.g. resilience, reversibility, regime shifts or others, are not yet well understood. In this session we invite contributions that investigate and analyze responses of aquatic ecosystems to changing conditions and aim at a better understanding of the meachisms behind ecosystem response patterns. All studies, whether they are based on the analysis of paleo- and field data or utilize experimental or numerical approaches, that support a process based understanding of the ecosystem responses are welcome.

This session will be organized by the RTG R3, Konstanz.

Vortragsspache: Englisch

Biofilms in fluvial ecosystems are spatially and temporally heterogeneous conforming microbial landscapes. These landscapes are modulated by physical habitat heterogeneity shaping both local biodiversity (structure and composition) and meta-community dynamics. The biogeochemical processes carried out by these microbial communities are affected by the physical habitat heterogeneity. The relationship between the structure and function of microbial landscapes is unclear as well as how it translates across scales determining biogeochemical processes at the reach scale, which is the scale at which nutrient cycling is determined and streams are managed. Our goal in this session is to explore the relationships between small scale biofilm properties and larger scale biodiversity and biogeochemistry. We invite contributions focusing on drivers of microbial community structure and function as well as upscaling approaches.

Session chairs: Anna Oprei, Ute Risse-Buhl

Vortragsspache: Englisch & Deutsch

Gesetzliche Vorgaben, Richtlinien und Verordnungen erfordern die Erfassung aquatischer Lebensgemeinschaften in Oberflächengewässern, z. B. bei der naturschutzfachlichen Einschätzung wasserbaulicher Maßnahmen, der Erfassung der Biodiversität, der Früherkennung von invasiven Arten sowie der Bewertung des ökologischen Zustandes eines Wasserkörpers auch im Rahmen der EU-Wasserrahmenrichtline.

Für die biologischen Qualitätselemente Fische, Makrozoobenthos, Phytobenthos und Phytoplankton konnte das große Potenzial der DNA-basierten Erfassung einzelner Arten und Artengemeinschaften bereits in wissenschaftlichen Studien und Pilotprojekten dargelegt werden. Durch verschiedene nationale und internationale Anstrengungen wurden und werden derzeit für einige Organismengruppen und Probenarten praxisnahe Protokolle und Leitlinien entwickelt und standardisiert, um die DNA-gestützten Methoden in das behördliche Monitoring zu integrieren und für die ökologische Gewässerbewertung nutzbar zu machen.

Mit der Special Session bieten wir Forschenden und Anwendergruppen ein Forum, um Projekte und Ergebnisse zum aktuellen Stand der Methodenentwicklung und Standardisierung vorzustellen. Insbesondere soll die Special Session die Diskussion zu dem noch offenen Forschungsbedarf und bestehenden Grenzen der neuen Methoden mit Blick auf den Einsatz in Wasserwirtschaft und Naturschutz intensivieren.

Session Chairs: Sascha Krenek, Julia Kleinteich, Florian Leese, Till-Hendrik Macher

Vortragsspache: Englisch & Deutsch

The planktonic ecosystem is the largest on earth. Past limnological studies have substantially advanced our knowledge in understanding the wider role of plankton in ecology, evolution, and ecosystem functioning. This session aims to offer a forum for sharing recent results of studies in theoretical, experimental, and empirical aspects of plankton ecology to communicate the state-of-the-art in plankton research. The session calls for contributions of studies investigating e.g. biotic interactions and dynamics in plankton communities or the effects of environmental stressors, change, or variability on plankton organisms or communities. For instance, understanding the effects of environmental stressors on the physiology and ecology of plankton organisms is important for predicting the consequences of ongoing environmental changes on plankton communities and their dynamics. Studies investigating the effects of multiple environmental drivers or more complex food web interactions are especially welcome. Observational plankton studies are accepted, but preference will be given to hypothesis-driven studies that are conceptually well based on theory and report results of microcosm or mesocosm experiments, or ecological models. Contributions in English are preferred.

Session-Chair: Erik Sperfeld and Maria Stockenreiter

Vortragsspache: Englisch

Im Zuge der Umsetzung verschiedener Richtlinien und Gesetze nimmt die Zahl an Gewässer- und Auenrenaturierungen stetig zu. Gerade für die Flora und Fauna der Ufer und Auen zeigen sich teils gute Erfolge, jedoch unterscheiden sich die Bewertungsansätze oft erheblich.Die Session soll einen Einblick in die verschiedenen Ansätze in der Auenforschung geben sowie den Nutzen und Wert für die Gewässerforschung und –bewertung erörtern. Im Fokus können dabei Erfolgskontrollen von Renaturierungsmaßnahmen stehen, die sich mit der Flora und Fauna von Auen, mit morphologischen und hydrologischen Grundbedingungen oder planerischen Herausforderungen beschäftigen. Auch Beträge, die auenrelevante Ökosystemfunktionen und- leistungen in der Planung und Evaluation integrieren, sind willkommen. Insgesamt soll mit dieser Session ein Forum geboten werden, in dem Effekte von Renaturierungsmaßnahmen und deren Bewertung über den Gewässerrand hinaus im Kontext des Auenmanagements diskutiert werden.

Session chairs: Kathrin Januschke, Mathias Scholz, Barbara Stammel

Vortragsspache: Englisch & Deutsch

The European Commission defined the Nature-based solutions (NBS) as living solutions inspired by, continuously supported by and using nature. They are designed to address various environmental challenges in a resource efficient and adaptable manner and to provide simultaneously economic, social and environmental benefits. NBS have been identified as crucial for ecosystem regeneration and improvement of human well-being, socio-ecological resilience, and multi-functional watershed management. At the level of the hydro-system, NBS are for example river restoration, wetland reactivation, floodplain management, riparian forest protection. NBS implementation face challenges as a missing proof of concept. Are NBS effective and sustainable? Which co-benefices are they delivering? We propose to bring together some of the emerging and leading researchers on NBS applied to the hydro-system. The session aims to increase our understanding of the NBS benefices, provide insight into NBS limits and formulate recommendations. Presentations will encompass for example remote sensing methods, ecosystem services assessment, estimation of ecological recovery, simulation under climate scenario, high resolution imaging techniques for measuring ecosystem vitality and biodiversity, so as tools to guide decision-making.

Session-Chair: Aude Zingraff-Hamed

Vortragsspache: Englisch

Declining functional diversity reduces the capability of ecological systems to buffer against biotic and abiotic changes and to maintain ecosystem functions. This, in turn, enhances further biodiversity loss. This session addresses this understudied feedback loop by accounting for the biodiversity-related flexibility of ecological systems, which enables them to adjust to for example altered predation, prey availability, or abiotic conditions. Trait adjustment may arise from phenotypic plasticity, shifts in community composition or evolution. We invite discussions of results from experimental approaches, field measurements and mathematical modelling, ideally comprising two or more trophic levels. We will have a mixture of talks, posters, discussion groups, and open space for more informal working groups.

This session is organized by Dynatrait.

Vortragsspache: Englisch

Detecting biodiversity in aquatic systems and studying processes that contribute to biodiversity changes require reliable tools for identifying and quantifying species and their traits. Advances in (semi-)automated imaging techniques for planktonic organisms allow processing of large numbers of individuals. Combined with image analysis through computer vision, machine learning, and/or deep learning, these techniques can be powerful tools for studying biodiversity at high temporal and spatial resolution. Several imaging and analysis approaches are under development and some are already being implemented. This session invites contributions presenting current approaches, method development, protocols, and studies that use imaging techniques to study biodiversity. In particular, the session will serve to discuss common approaches and limitations.

Session chair: Lutz Becks and co-chairs.

Vortragsspache: Englisch

Taxonomie/Biologie/Evolution/molekulare Ökologie/Biogeographie