Experimental Food Webs
„PNRR: Funds for a modern and reformed Romania!”
Predictive food web models for aquatic ecosystems (PredAqua)
- Principal Investigator: Dr. Ferenc Jordan
- Funding Contract: 760102/23.05.2023
- Project Code: CF 72/14.11.2021
- Beneficiary: Institute of Biological Research Cluj, branch of the National Institute of Research and Development for Biological Sciences (INCDSB), Bucharest
- Funding: PNRR/2022/C9/MCID/I8 - Development of a program to attract highly specialized human resources from abroad in research, development and innovation activities
- Project Duration: 24 months
- Start Date: 01.07.2024
- End Date: 30.06.2026
- Budget: 4.620.000 RON (929.577 Euro)
- Short description: Our project addresses the question of how to assess and improve the predictive power of food web models. We perform experimental food web research in freshwater mesocosms, supported by static and dynamic network analysis. We test the predictability of a range of models by comparing simulations and community dynamics in the mesocosms.
- General Objectives: The project aims to develop and validate an innovative framework for the predictive modelling of aquatic ecosystems by integrating network analysis and dynamic simulations with controlled mesocosm experiments, in order to enhance the capacity to predict the responses of biological communities to multiple disturbances.
Project team
Dissemination of results, capacity building, and scientific activities within the PredAqua project
Within the PredAqua project, team members participated in national and international scientific conferences and events, research and training visits, summer schools, and knowledge-transfer activities. These activities contributed to the dissemination of project results, the development of team expertise, the strengthening of international collaborations, and the implementation of the experimental activities planned within the project.
Participation in conferences and scientific events
Interdisciplinary CYANOACTION WG1–5 Meeting
Chania, Greece | 1–4 May 2025
Bogdan Drugă participated in the interdisciplinary CYANOACTION WG1–5 Meeting, held at the Cultural Center of Chania. The event brought together members of all five CYANOACTION Working Groups and focused, among other topics, on identifying key stakeholder groups relevant to harmful cyanobacterial blooms and developing approaches for stakeholder engagement.
Participation in the meeting facilitated scientific exchange and the development of new research collaborations. In this context, joint experiments relevant to the objectives of the PredAqua project were discussed and planned, including collaborative activities with researchers from the University of Geneva, Switzerland.
The 32nd International Symposium “Deltas and Wetlands”
Tulcea, Romania | 12–17 May 2025
PredAqua team members and collaborators participated in the 32nd edition of the international symposium “Deltas and Wetlands”, contributing four scientific presentations: two oral presentations and two posters.
- Drugă, B., Briddon, C.L., Nicoară, M., Hegedűs, A., Thomas, M.K.
“Evolution in action: Skeletonema marinoi’s adaptive growth to climate extremes”
Type of contribution: oral presentation - Nicoară, M., Pripon, A., Baiu, A., Drugă, B.
“Acclimation vs adaptation: a study on the thermal tolerance of cyanobacterium Microcystis aeruginosa”
Type of contribution: oral presentation - Santos, G., Pop, M.M., Ger, K.A., Drugă, B., Jordán, F.
“Feeding selectivity and trophic links of a dominant cyclopoid copepod”
Type of contribution: poster - Jordán, F., Patonai, K.
“Spatial variability of the Danube river food web”
Type of contribution: poster
14th Symposium for European Freshwater Sciences – SEFS14
Bolu, Türkiye | 20–25 July 2025
The team participated in SEFS14 – 14th Symposium for European Freshwater Sciences, one of the major European scientific events dedicated to freshwater ecosystems. PredAqua team members and collaborators delivered four oral presentations.
During the event, Bogdan Drugă was also invited to chair a scientific session.
- Drugă, B., Nicoară, M., Tripon, A., Lawton, L., Edwards, C.
“Toxin production in Microcystis aeruginosa under elevated temperature and CO₂: short- vs. long-term responses”
Type of contribution: oral presentation - Nicoară, M., Pripon, A., Drugă, B.
“Changes in thermal tolerance of diatom Mayamaea permitis after 3 years of exposure to warming”
Type of contribution: oral presentation - Santos, G.S., Pop, M.M., Ger, A., Drugă, B., Jordán, F.
“Feeding of a dominant copepod species in a temperate impacted lake”
Type of contribution: oral presentation - Pop, M.M., Mot, A.C., Di Lorenzo, T., Moldovan, O.T., Iepure, S.
“Life goes on in a stinky world: exploring the tolerance of copepod crustaceans to hydrogen sulfide in the Movile Cave, Romania”
Type of contribution: oral presentation
5th International Conference on Community Ecology – ComEc5
Budapest, Hungary | 3–5 September 2025
Team members and collaborators participated in the 5th International Conference on Community Ecology – ComEc5, where five oral contributions were presented.
Ferenc Jordán was also involved in the scientific organization of the conference.
- Drugă, B., Nicoară, M., Tripon, A., Pop, M.M.
“The adaptive responses of Skeletonema marinoi under long-term global change scenarios”
Type of contribution: oral presentation - Santos, G., Pop, M.M., Ger, K.A., Drugă, B., Jordán, F.
“Feeding selectivity and trophic links of a dominant cyclopoid copepod”
Type of contribution: oral presentation - Nicoară, M., Briddon, C.L., Mortu, A., Vințan, R., Hegedűs, A., Gal, E., Drugă, B.
“Warming and acidification alter essential fatty acid profiles in marine diatom Skeletonema marinoi”
Type of contribution: oral presentation - Tripon, A-M., Jordán, F., Vasquez, R.F., Hampel, H.
“Comparing co-occurrence network methods for assessing invertebrate associations in a river ecosystem”
Type of contribution: oral presentation - Jordán, F., Liu, W.
“Interaction profiling species and functional redundancy in ecological networks”
Type of contribution: oral presentation
AtlantECO Final Scientific Conference: “One Ocean, One Health – Microbiomes of the Atlantic Seascape”
Ponta Delgada, Azores, Portugal | 15–19 September 2025
Team members participated in the final scientific conference of the AtlantECO project, organized under the theme “One Ocean, One Health – Microbiomes of the Atlantic Seascape”. The event brought together researchers from AtlantECO, representatives of other European and international projects, and stakeholders involved in the development and implementation of marine environmental policies. Two oral presentations were delivered.
Ferenc Jordán also served as co-chair of the “Food Provision” session.
- Drugă, B., Nicoară, M., Tripon, A., Pop, M.M., Hegedűs, A.
“Long-term adaptation of an abundant marine diatom to global change drivers”
Type of contribution: oral presentation - Jordán, F., Andras, H., Chaffron, S.
“Diversity of co-occurrence networks: key nodes and functioning”
Type of contribution: oral presentation
Joint International Conference of the MikroBioKosmos Society & Central and East Europe Symposium of Microbial Ecology – MBK/CEESME 2025
Thessaloniki, Greece | 22–24 September 2025
PredAqua team members participated with two oral presentations in the joint international conference organized by the MikroBioKosmos Society and the Central and East Europe Symposium of Microbial Ecology (CEESME). The contributions were presented within sessions dedicated to environmental microbiology and microbial ecology.
- Drugă, B., Nicoară, M., Tripon, A., Pop, M.M., Hegedűs, A.
“Long-term adaptation of an abundant marine diatom to global change drivers”
Type of contribution: oral presentation - Szekeres, E., Teban-Man, A., Tripon, A-M., Jordán, F.
“Bacterial functional groups: classification and cultivation challenges in food web research”
Type of contribution: oral presentation
BIOTA Symposium – “Biodiversity, Traditions and Present”, 11th Edition
Cluj-Napoca, Romania | 8–9 May 2026
Project members participated in the 11th edition of the BIOTA Symposium – “Biodiversity, Traditions and Present”, within the session dedicated to ecology and biodiversity conservation.
- Jordán, F.
“A systems view on ecological communities: experimentally testing model predictions”
Type of contribution: oral presentation - Drugă, B.
“Learning from Failure: How Mistakes Shape a Career in Science”
Type of contribution: oral presentation
Gordon Research Conference – Marine Microbes 2026 “Decoding the Marine Microbial World: Currencies, Interactions and Environmental Controls”
Castelldefels, Barcelona, Spain | 7–12 June 2026
Bogdan Drugă participated as an invited speaker at the 2026 Gordon Research Conference on Marine Microbes, an international conference focused on frontier research in marine microbiology and the ecology of aquatic microorganisms.
- Drugă, B.
“Long-Term Adaptation of an Abundant Marine Diatom in a Warming Ocean”
Type of contribution: oral presentation – invited speaker
Research visits, training, and professional development
Mesocosm experiment and research training at the Scottish Association for Marine Science – SAMS
Oban, Scotland | 15 October – 16 November 2024
Bogdan Drugă, Maria Nicoară, Maria-Mirabela Pop, and Andreea Tripon carried out research and training activities at the Scottish Association for Marine Science (SAMS), Oban.
One of the main activities consisted of conducting a mesocosm experiment using natural aquatic communities. The mobility contributed to the development and consolidation of expertise in the design, implementation, and monitoring of experiments involving natural aquatic communities in mesocosm systems, as well as the application of these approaches within the experimental activities of PredAqua.
Specialized training in flow cytometry – Hellenic Centre for Marine Research
Heraklion, Greece | 23–29 November 2024
Maria Nicoară completed a training visit at the Hellenic Centre for Marine Research (HCMR) focused on the use of flow cytometry for the analysis of planktonic communities.
The programme combined theoretical instruction with practical training and contributed to the development of the knowledge and skills required to design, conduct, and interpret flow-cytometry experiments applied to aquatic plankton communities.
Specialized training – Robert Gordon University
Aberdeen, Scotland | 2–8 February 2025
Andreea Tripon completed a specialized training visit at Robert Gordon University, focused on the analysis of cyanobacterial toxicity data and the application of data-analysis methods to studies involving natural aquatic communities and mesocosm experiments.
The training contributed to the development of expertise in the processing and interpretation of experimental data relevant to PredAqua activities.
International summer school – “Network analysis in ecology: different approaches for complex ecological systems”
University of Parma, Parma, Italy | 17–19 June 2025
Participants Andreea Tripon, Maria Nicoară, and Gleice de Souza Santos. The international summer school focused on different approaches to network analysis in ecology, with particular emphasis on the characterization of complex ecological systems.
Participation contributed to the development of expertise in the construction, analysis, and interpretation of ecological networks and their application to the study of relationships among components of biological communities, one of the core methodological directions of the PredAqua project.
Synergy summer school 2025 – “Complexity and emergence in marine ecosystems/seascape: theory, mechanisms and data”
Ischia, Italy | 30 June – 4 July 2025
Participants Gleice de Souza Santos and Maria Nicoară. The summer school, organized in the context of the AtlantECO and Mission Atlantic projects, focused on complexity and emergent processes in marine ecosystems. The programme covered topics including complex-systems theory and theoretical ecology, interactions between biological and physical processes, climate dynamics, advanced data analysis, ecological niche modelling, bioinformatics, and marine food-web analysis.
Participation contributed to the development of expertise in analysing and modelling complex ecological systems relevant to the objectives of PredAqua.
Short-term scientific mission – Robert Gordon University
Aberdeen, Scotland | 28 September – 4 October 2025
Bogdan Drugă carried out a research visit / Short-Term Scientific Mission at Robert Gordon University, working in collaboration with Prof. Christine Edwards, Prof. Linda Lawton, and Dr. Diana Moura.
The activities focused on the effects of heatwaves on planktonic communities and on the analysis of the chemical composition of phytoplankton biomass. The mobility also contributed to strengthening international collaboration and to developing the scientific basis for a joint project proposal submitted under the Water4All 2025 call.
Knowledge transfer, teaching contributions, and science communication
International course on ecological network analysis: Ferenc Jordán – “Introduction to ecological network analysis”, 10–13 February 2025, online, University of Cape Town, South Africa
Invited lecturer: Ferenc Jordán – “Environmental change in Central Europe: Challenges and adaptation”, 5 March 2025, Center for Inner Asian Studies, Indiana University, Bloomington, Indiana, USA
Invited lecturer: Ferenc Jordán – “Breaking boundaries: the hacking of Earth’s ecosystem”, 25 April 2025, World Adaptation Forum, Budapest, Hungary
Teaching contribution as lecturer: Ferenc Jordán – “Variability of network topology at various levels of organization: different approaches for complex ecological systems”, 17–19 June 2025, International Summer School “Network analysis in ecology”, University of Parma, Italy
Teaching Contribution as lecturer: Ferenc Jordán – “Variability of network topology at various levels of organization”, 3–5 June 2026, International Summer School “Network analysis in ecology”, University of Parma, Italy
Invited speaker: Maria Nicoară – “Research: between agony and ecstasy”, 7 May 2025 , Eco Days, Cluj-Napoca, Romania
Invited panelist: Maria Nicoară – “How to Create Opportunities Through Networking”, 27 October 2025, AQUACOSM-plus Early Career Researcher Workshop – “Building Bridges for Career Success”
Scientific and experimental activities
Project launch and team development
1 July 2024
The PredAqua project team was established and introduced, with scientific coordination developed together with Dr. Ferenc Jordán.
By integrating expertise in aquatic ecology, microbiology, plankton ecology, and ecological network analysis, the project aims to investigate the structure and functioning of aquatic communities through a combination of ecological experimentation and network analysis and modelling approaches.
At this stage, Ferenc Jordán, Maria-Mirabela Pop, and Andreea Tripon joined the team of the Institute of Biological Research Cluj-Napoca for the implementation of PredAqua activities.
International expert consultations on aquatic ecology and mesocosm experiments
8–12 September 2024 | Cluj-Napoca
During the initial stage of the PredAqua project, consultations were organized with international experts in aquatic ecology, plankton ecology, and mesocosm experimental systems in order to optimize the project methodology.
The invited experts were:
- Dr. Jens Nejstgaard – IGB Berlin, Germany
- Dr. Stella Berger – IGB Berlin, Germany
- Dr. Maria Stockenreiter – LMU Munich, Germany
The consultations focused on improving the experimental design, exploring alternative approaches for constructing and interpreting trophic networks, and optimizing experiments with natural aquatic communities in mesocosm systems.
The invited experts also delivered scientific presentations and participated in discussions covering aquatic ecology, international scientific collaboration, the development of more inclusive research practices, and the identification of funding opportunities.
The activity contributed to the validation and refinement of the methodological approach subsequently applied in PredAqua experiments.
Scientific event – Co-occurrence Network Analysis
20 March 2025 | Institute of Biological Research Cluj-Napoca
A scientific event dedicated to current challenges in ecological network analysis and co-occurrence network analysis was organized within the PredAqua project.
Speakers:
- Dr. Ferenc Jordán – Institute of Biological Research Cluj-Napoca
- Dr. András Hidas – Centre for Ecological Research, Budapest
The presentations and discussions addressed conceptual and methodological differences between species co-occurrence and actual biological interactions, as well as major challenges related to data analysis, algorithm selection, and ecological network construction.
The activity contributed to the development and harmonization of methodological approaches used for analysing biological communities within PredAqua.
First PredAqua experiment with natural aquatic communities in mesocosm systems
March–April 2025 | Cluj-Napoca
In spring 2025, one of the core experimental activities of the PredAqua project was carried out: an intensive study involving natural aquatic communities in mesocosm systems.
Approximately 7,000 L of water were collected from Lake No. 3, Gheorgheni, Cluj-Napoca, and used to fill seven experimental mesocosms.
A total of 32 types of perturbations were tested, resulting in 231 parallel experimental tests using dialysis bags through different combinations of treatments.
The ten-day experiment investigated how the introduction of bacterial, microalgal, and zooplankton species influences biodiversity, community structure, and the stability of aquatic ecosystems.
The activities were carried out with the support of Dr. Maria Stockenreiter (LMU Munich) and students from Babeș-Bolyai University, Cluj-Napoca.
Second PredAqua experimental phase in mesocosm systems
March–April 2026 | Cluj-Napoca
In spring 2026, a second PredAqua experimental phase involving aquatic communities in mesocosm systems was carried out.
The activity continued the experimental approach developed and tested during the previous phase and aimed to generate data required to assess the response of aquatic communities to perturbations and to analyse their stability and structure using experimental approaches combined with ecological network analysis.
Sampling and monitoring campaigns
June 2024 – June 2026
Sampling campaigns were carried out throughout the implementation period as part of the experimental and monitoring activities of the PredAqua project.
The campaigns aimed to collect biological and environmental samples required for the characterization of aquatic communities, the implementation of experimental studies, and the generation of data used to analyse community structure and ecological interactions.
Completion of the PredAqua project
30 June 2026 | Cluj-Napoca
The PredAqua project was completed on 30 June 2026 (Press release: https://icbcluj.ro/en/press-release-completion-of-the-predaqua-project/), after 24 months of implementation.
During this period, the planned experimental, analytical, modelling, dissemination, and training activities were carried out, concluding the implementation of the project in accordance with its objectives.
Images:
PNRR. Funded by the European Union – NextGenerationEU
