Nature-based adaptation in human dominated coastal ecosystems

Abstract

Ecosystems along river-to-sea continuums face urgent challenges that demand swift restoration interventions, often exceeding the data availability, collection and testing capacity. This makes expert- and consensus-based approaches vital for guiding decisions, particularly in data-scarce coastal regions. With the aim to provide practical guidance for assessing the applicability of different restoration techniques, this study involved a group of 23 experts from various European and Mediterranean regions to evaluate 49 restoration techniques tested recently in nine sites, representing diverse coastal ecosystems. Through a Delphi-based expert elicitation, a series of gray, hybrid, and green restoration techniques was assessed in terms of their structural and functional performance. Additionally, the assessment of the pressures affecting the regions allowed exploring the restoration techniques' resilience to both natural and anthropogenic pressures and impacts. Results from the data collected so far suggest that, while green restoration techniques are environmentally friendly and significantly support natural processes, their limited scale of influence makes them vulnerable when pressures are strong or widespread on the ecosystem. This often leads to opting for hybrid or engineering-based solutions for restoration, as they provide a more robust structure and longevity albeit with reduced capacity to foster natural processes. This result underscores a critical dilemma: while green and/or integrated solutions can help mitigate human-induced impacts and digital tools may support decision-making, restoration efforts alone may sometimes be insufficient if the underlying anthropogenic pressures on human-dominated coastal ecosystems remain unaddressed. Subsequently, the identified techniques and their performance evaluated under current and future conditions have been compiled into an open-source, interactive digital tool, designed to assist decision-makers and practitioners in selecting the most suitable restoration strategies by leveraging the knowledge acquired through ongoing experiences in coastal restoration. This digital platform not only facilitates access to information but also enables the integration of new data on emerging techniques, making it a dynamic and evolving resource for coastal restoration management.

This work has partially been funded from the European Union's Horizon 2020 Research and Innovation Action under Grant Agreement No◦101037097 (EU- REST-COAST - https://rest-coast.eu/). The authors would like to acknowledge Dr. Elisa Furlan, Dr. Francesca Coccon, Dr. Ing, Pierpaolo Campostrini, Dr. Ing. Valerio Volpe, and Dr. Cristophe Briere, for their collaboration throughout the project. This study was partly carried out within the RETURN Extended Partnership (AB) and received funding from the EU's NextGenerationEU (National Recovery and Resilience Plan – NRRP, Mission 4, Component 2, Investment 1.3 – D.D. 1243 2/8/2022, PE00000005).

Peer Reviewed

Article signat per xx autors/es: Fabienne Horneman a,b,1, Alice Stocco b,1, Paolo Comandini c, Alberto Barausse c, Nuno Caiola d, Agustín Sánchez-Arcilla e, Vicente Gracia f, Richard Marijnissen g, Sara Pino Cobacho g, Luciana Villa Castrillon h,i, Joanna Staneva h, Elitsa Hineva j, Nataliya Andreeva j, Massimiliano Marino k, Rosaria Ester Musumeci k, Julien Dalle l, Mathis Cognat l, Olivier Boutron m, Morgane Jolivet m, Avi Uzan n, Shiri Zemah-Shamir o, Gregorz Rozynski p, Elisa Furlan a,b, Ignacio Gatti a,b, Caterina Dabal`a q, Fabio Pranovi b, Andrea Critto b,a, Silvia Rova b,r, Silvia Torresan a,b,*

a CMCC Foundation - Euro-Mediterranean Center on Climate Change, Italy b b Department of Environmental Sciences, Informatics and Statistics, University Ca’ Foscari Venice, Via Torino 155, 30172 Venezia, Italy c Department of Biology, University of Padova, via U. Bassi 58/B, 35131 Padova, Italy d Eurecat, Technology Center of Catalonia, Dept. Climate Solutions and Ecosystem Services, Spain e Universitat Polit`ecnica de Catalunya (UPC), Spain f Laboratori d'Enginyeria Marítima, Universitat Polit`ecnica de Catalunya, Jordi Girona, 1 - 3, M`odul D1, Barcelona 08034, Spain g Deltares, Boussinesqweg 1, Delft 2629HV, the Netherlands h Institute of Coastal Systems - Analysis and Modeling, Helmholtz-Zentrum Hereon, Geesthacht, Germany i Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Wilhelmshaven, Germany j Institute of Oceanology, Bulgarian Academy of Sciences, 40 Parvi may Blvd., 9000 Varna, Bulgaria k Department of Civil Engineering and Architecture, University of Catania, Via Santa Sofia 64, 95123 Catania, Italy l Seaboost, 34000 Montpellier, France m Tour du Valat Research Institute, 13200 Arles, France n Israel Nature and Park Authority (INPA), Israel o School of Sustainability, Reichman University, 8 Ha'Universita st.Herzliya, Herzliya 4610101, Israel p Institute of Hydro-Engineering, Polish Academy of Sciences, 7 Ko´scierska, 80-328 Gda´nsk, Poland q Consortium for Coordination of Research Activities Concerning the Venice Lagoon System (CORILA), San Polo 19, 30125 Venezia, Italy r International Centre for Climate Change Research and Studies, San Marco 2847, 30124 Venice, Italy

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