Final Report Summary - HYTECH (HYDRODYNAMIC TRANSPORT IN ECOLOGICALLY CRITICAL HETEROGENEOUS INTERFACES) SUMMARY OF PROJECT OBJECTIVESHYTECH is an Initial Training Network of eleven Early Stage Researchers (ESRs) and four Experienced Researchers (ERs) (http://hytech.dii.unipd.it). The main objective of HYTECH was to study the physical, biochemical and ecological processes acting at interfaces in natural surface water bodies. The overall topic of the research program focused on the transport processes in fluvial and wetland environments, which are controlled by hydrodynamic exchanges between the main flow channels, the sediment beds, banks and submerged and emergent vegetation, and by bio-geochemical interactions. The Network has 10 Full Partners and 7 Associate Partners, ranging from Universities, Research Institutes, SMEs and public authorities all with a common interest in the management of the quality of aquatic environments. Hydrodynamic transport processes of solutes, contaminants and sediments were investigated as this involved studying relationships with ecological communities and the vulnerability of natural water bodies to water quality problems. Fellows received an advanced training on fundamental theories and on innovative methods to enable both research and applications to be taken beyond the current state of the art, by pursuing a clearly defined set of scientific and technological objectives that are identified by four research-oriented Work Packages:- Objective 1 (Environmental Assessment, River Vulnerability and Renaturalization) was to develop river management tools and novel design of river hydraulic applications devoted to protection and control of riverine environments, to promote optimal implementation of environmental strategies, and to improve the effectiveness of such applications, in an attempt to optimize water resource exploitation, while maintaining high ecological standards.- Objective 2 (Flow-Biota Interactions: Interface Biological and Ecological Structures) was to advance the existing capabilities of observing, measuring and modelling the turbulent flow field around aquatic biota, and to shed new light on the complex interactions occurring at interfaces in aquatic environments between flowing water, sediment particles, nutrient dynamics and submerged plants.- Objective 3 (Applied Hydrodynamics ff Vegetated Streams) was to gain detailed knowledge of the physical processes occurring at the interface of water with sediment and aquatic vegetation, which will help to initiate and support morphodynamic processes allowing the development of new management techniques for streams. The aim is to enable streams to develop themselves towards a dynamic equilibrium with self-organised vegetation patches rather than to construct a pre-defined static situation which requires constant monitoring and maintenance.- Objective 4 (Interface Transport of Dissolved, Suspended And Granular Matter) was to develop new flow-sediment interface models that reflects both the multiple scales (starting from a grain scale) and the mobility of the interface, based on rigorous definitions of the key processes involved (entrainment, transport, deposition).S&T RESULTS AND FOREGROUNDS AND SOCIO-ECONOMIC IMPACTSediment and biota interactions with turbulent flows in riverine environments were primarily assessed through extensive experimental surveys, which encompassed both tests in controlled laboratory conditions and observations in monitored field scenarios, combined with the development of conceptual, mathematical and numerical models.WP1. ENVIRONMENTAL ASSESSMENT, RIVER VULNERABILITY AND RENATURALIZATION.Within this WP, ESR05 (University of Padua) and ESR07 (WET Engineering S.r.l.) worked on the definition (i) of a physically-based parameter to assess the vulnerability of surface water bodies to surface-generated pollution, and (ii) of optimal design criteria of wetlands in terms of geometry and of vegetation distribution such as to achieve increased levels of pollutant removal. Their work provided a quantitative understanding on the correlation between design parameters of wetlands and their hydraulic efficiency, and on the evidence of distinct patterns of solute dispersion in water bodies that are different in morphology, substrate material, and presence of submerged vegetation. Such an understanding will have a significant impact on the effectiveness of remediation actions that must be implemented to protect vulnerable aquatic systems through the design of more efficient and cost-effective green infrastructures.ESR09 (TU Braunschweig) and ER03 (gIR Engineering) investigated the effects of the design of nature-oriented structures implemented for river restoration purposes on river flows and bed morphology, in light of a detailed analysis carried out on the EU Water Framework Directive (WFD, 2000/60/CE) and on the EU Floods Directive (FD, 2007/60/CE), which revealed their contradicting demands and/or synergetic effects. Their work gave an insight into the interaction between design parameters of nature-oriented structures and the resulting river flow and morphology. The understanding of this interaction is very important to predict and control hydrological and morphological processes through proper design of these structures, which will have an impact on the design of river restoration projects where nature-oriented structures are used for bank protection combined with habitat restoration purposes. The analysis also highlights that new monitoring programmes are necessary to take into account hydromorphological aspects into River Basin Management (WFD) and Flood Risk Management (FD) Plans, in order improve the overall management of river systems by Water and Environmental Authorities.WP2. FLOW/BIOTA INTERACTIONS. INTERFACE BIOLOGICAL AND ECOLOGICAL STRUCTURES.Fellows recruited at the University of Aberdeen worked as a team group to identify and quantify key flow-organism interactions and ecologically-relevant processes in rivers, by developing (i) a unifying mathematical framework for the integration of fluid mechanical, ecological and biomechanical processes (ESR01), and (ii) an advanced new experimental methodology and instrumentation for field tests at selected river sites. The new set equations describing flow biota interactions and the technical and methodological developments presented in this study will significantly improve the predictive capabilities of hydrodynamics models developed for applications in riverine environments and will assist future studies seeking to pursue laboratory accuracy in the field.These results were complemented by the research carried out by ESR03 (National Centre for Scientific Research), who investigated how riverine environments affect the growth and distribution of aquatic plants, which, in turn, are ecosystem engineers that actively modify their own habitat, and by ER04 (University of Padua), who studied the influence of organic and cohesive sediments on river bed stability. Their research emphasizes the role of aquatic plant morphology and of bioturbation processes in affecting flow and sediment dynamics in rivers. This understanding will have a significant impact on river management, conservation and restoration, which must ensure a balance between control of flood risk and protection of ecosystem biodiversity.WP3. APPLIED HYDRODYNAMICS OF VEGETATED STREAMSESR02 (TU Braunschweig) and ESR04 (Royal Netherlands Institute for Sea Research) analyzed the effects on turbulent flow and on self-organization of submerged vegetation of (i) complex interactions between different roughness elements (e.g. gravel beds, vegetated streams) and of (ii) aquatic plants having different architectural complexity and mechanical properties. Their research provided evidence of significant spatial aggregation of different vegetation species, due to positive effects induced by other plants regulating water levels and ensuring flow conveyance throughout the annual growth cycle. On the other hand, excessive aquatic vegetation in rivers can be detrimental as it may increase the risk of flooding, thus suggesting that complex interactions between composite bed surfaces and the turbulent water flow cannot be neglected. Potential applications of the research will inform river management such as to achieve an optimal balance between maintaining habitats and providing flow regulation services, while minimizing flooding risks. This will contribute to development of guidelines for the restoration of river ecosystems in order to maximize aquatic biodiversity.The research component on fundamental processes carried out within WP3 was complemented by the prototype development of a new technique based on fiber-optic sensors for the measurement of flow turbulence parameters (ER01, GHT Photonics S.r.l.). Although the application of fiber optical sensors is not new in fluid mechanics, a step forward was accomplished in this project by presenting a a unique methodology to acquire measurements of flow turbulence (voriticity), which cannot be otherwise measured in a direct way to date.WP4. INTERFACE TRANSPORT OF DISSOLVED, SUSPENDED AND GRANULAR MATTERESR08 (Politecnico di Milano) and ESR11 (University of Sheffield) implement advanced measuring methods to observe grain motion at the highest spatial and temporal resolutions, in order to improve currently-available modelling techniques for sediment transport in rivers. The development of new laboratory facilities and the improvement of image-based techniques proved to overcome previous experimental limitations by obtaining full description of bed-load particles motion and enabled a significant advancement in terms of image data acquisition and processing. Traditional models for sediment transport processes were usually conceived for large scale processes, often neglecting mechanisms occurring at the small scale. Grain-scale measuring techniques shall serve as a basis for a comprehensive treatment of sediment dynamics, whichis in line with the priorities given by the EU Directives 2000/60/EC and 2007/60/EC putting an emphasis on river sediments, that are recognized as a key quality element for ecological status of surface waters and as a worsening factor for flood risk.The laboratory component of the research carried out within WP4 was complemented by numerical modelling to simulate suspended sediment transport over permeable beds (ESR10, University of Sheffield), and by prototype development of a new technique based on temperature sensors for the measurement of bed topography in rivers (ER02, GHT Photonics S.r.l.). Current empirical approaches to estimate fine sediment conveyance fail to address the physical structure of natural streams. The new model (based on Smoothed Particle Hydrodynamics approach, SPH) provides a macroscopic description of flow field by simplifying the complicated turbulence mechanisms at the bed, thus efficiently solving practical cases of interest with satisfactory accuracy. Estimating fine conveyance sediment and measuring bed elevation with reliable accuracy is crucial in many river engineering applications, such as controlling erosion and deposition around hydraulic structures (e.g. spurs, dykes, weirs, bridges), or bathymetric survey, which is to date one of the most time and money consuming monitoring activity.THE TRAINING PROGRAMME, DISSEMINATION AND OUTREACH ACTIVTIESHYTECH offered its ESRs advanced training in the area of environmental management of surface water bodies. The combined training through research and participation to a series of Summer Schools has provided the ESRs with a comprehensive educational and advanced professional competencies that has increased their employment opportunities in industrial enterprises, water companies, and governmental agencies, or to embark on a career as a researcher in academic or government research institutions in Europe. HYTECH held five Summer Schools on (1) Statistics and Numerical Methods (University of Bradford, 19-26 October 2013), (2) Fluid Mechanics and Flow-Biota interactions (University of Aberdeen, 11-20 May 2014), (3) Ecology of Aquatic Systems (University of Lyon, 3-12 October 2014), (4) Laboratory Methods in Fluid Mechanics (Technische Universitaet Braunschweig, 17-23 May 2015), (5) Case Studies on Environmental Assessment, Renaturalization and Decontamination (University of Padua, 28 September to 3 October 2015). As part of the programme, researchers were trained in complementary transferable skills important for their future professional success, including basic elements of scientific film making, seminars on financial aspects of research, and 1-day visits at engineering field sites and research facilities.During the 4-year project, HYTECH contributed to 28 peer-reviewed scientific articles in international journals and articles in book series, 32 papers or abstracts in proceedings in international conferences, and co-edited a book in the Springer monographic series 'Geo-Planet: Earth and Planetary Sciences'. The Network participated in over 20 international conferences, co-organized the XXXIV International School of Hydraulics (http://sh.igf.edu.pl) with the Polish Academy of Sciences, convened four dedicated sessions at widely participated international conferences, including the EGU General Assembly in 2015 and 2016 (European Geosciences Union, www.egu.eu) and IAHR River Flow 2016 (International Association for Hydro-Environment Engineering and Research, https://www.iahr.org) and organized the '1st International Symposium on Interfaces in Aquatic Ecosystems' as the Final Conference of the project.The Network has organized communication initiatives that were accessible and understandable for members of the general public, including a series of five Open Days for primary and high school students. Early-Stage and Experienced Researchers could then convey their messages to lay and proficient audiences throughout the life of the project. The primary goal of the public engagement foreseen in HYTECH was to increase public consciousness on environmental, water-related societal problems in order to expose students from schools and universities to science and innovation and to develop their motivation to embrace research careers. One major deliverable was the production of a scientific video-documentary that describes the relationship between man and surface water bodies in a changing climate condition, by illustrating laboratory and field activities carried out across Europe at different partner institutions by the recruited fellows (https://vimeo.com/196245548).The overall impact of HYTECH was to produce in-depth knowledge of processes involving vegetation, pollutants and sediment in aquatic environments, which are essential in the assessment of vulnerability, enhancement and restoration of water bodies. This was pursued by providing young researchers and with interdisciplinary knowledge of fluid mechanics and aquatic ecology. This is particularly timely as emerging priorities of sustainable use of water resources and challenges of climate change recently led to new national and international statutory policies. This new generation of researches will play a crucial role in the development of sustainable management strategies of natural and constructed surface water bodies. It is therefore important for the EU to continue investing resources and developing human capital to expand on this excellence and so increase its competitiveness.Website: http://hytech.dii.unipd.itCONTACT INFORMATIONProf. Andrea MarionDepartment of Industrial EngineeringUniversity of Paduaemail: andrea.marion@unipd.it
