SISTER - The role of Soil-roots Interactions in Sustaining Tidal marsh Elevation against sea-level Rise

PIANO NAZIONALE DI RIPRESA E RESILIENZA
MISSION 4 - “Education and Research”
COMPONENT 2 - “From Research to Business”
INVESTMENT 1.2 - “Funding projects presented by young researchers”

TITLE: The role of Soil-roots Interactions in Sustaining Tidal marsh Elevation against sea-level Rise
ACRONYM: SISTER
Avviso pubblico MUR 247/2022 “Avviso pubblico per la presentazione di proposte progettuali”
Decreto Ministeriale di concessione prot. n. 564 del 13/12/2022 – sez. “Seal of Excellence”

HOST DEPARTMENT: ICEA - Department of Civil, Environmental and Architectural Engineering

SUMMARY
Restoration and preservation of coastal wetlands is one of the main targets of the UN Sustainable Development Goals and a priority of the European Union within the Green Deal framework. Among coastal wetlands, tidal salt marshes provide crucial ecosystem services for the well-being of society, including biodiversity, clean waters, storm protection, food supply, and carbon storage. However, salt marshes are lost at an unprecedentedrate due to the overwhelming stress caused by human interference and climate change. The resilience of such ecosystems is strictly connected to their elevation with respect to mean sea level. Alterations to this delicate ‘equilibrium’ may induce salt marshes to disappear. Auto-compaction, deep land subsidence, sedimentation decrease, and sea level rise are the main factors contributing to salt marsh drowning. For the first time, the SISTER project aims at deeply investigating the feedbacks among these processes to ultimately fill the scientific gap on the long-term fate of salt marshes under future climate change scenarios. The halophyte vegetation will represent the key linkage between surface and subsurface processes through branches, leaves, and roots. Specific objectives of the project are set to gain new knowledge on the mechanical behavior of soil-root systems in vegetated natural salt marshes and to provide technical advancements for construction of auto-sustainable salt marshes. The proposed solutions are based on the principle of ‘building with nature’ using lesson-learned from natural ecosystems (e.g., via optimal colonization strategies), expecting to foster policymaking plans on coastal preservation. SISTER is a multi/interdisciplinary project that connects different areas of expertise such as hydrodynamics, geomechanics, and wetland dynamics by employing innovative laboratory and field experiments to be integrated within a state-of-the-art modelling framework coupling surface and subsurface dynamics in transitional landforms.


OVERALL OBJECTIVES OF THE PROJECT
SISTER (The role of Soil-roots Interactions in Sustaining Tidal marsh Elevation against sea-level Rise) aims at improving our knowledge on the long-term survivability of natural tidal salt marshes, which is strictly related to their ability to maintain a certain elevation with respect to mean sea level. Alterations to this delicate “equilibrium” may induce salt marshes to disappear. Auto-compaction, deep land subsidence, sedimentation decrease, and sea level rise are the main factors contributing to salt marsh drowning. However, most of the previous research neglects the importance of coupling these processes occurring above and below the salt marsh surface. A coupling strategy is the fundamental next step to fill this literature gap, with vegetation playing a main role as it represents the linkage between above and below surface processes via branches, leaves, and roots. Novel evidences suggest that roots make stiffer (i.e., more resilient) marsh soils.
The SISTER project aims are twofold. First, it builds new scientific knowledge on the mechanical behavior of soil-root systems in vegetated natural salt marshes, understanding the role of roots in reinforcing the largely compressible marsh soils. This will allow to transfer the physics derived from the short-term measurements to long-term prediction models, providing the necessary characterization of the intrinsic properties of root-reinforced tidal marshes, which are crucial to predict their long-term fate under future climate change scenarios, e.g., variations of the sea-level rise (SLR) acceleration rates. Second, SISTER will provide the technical advancements to design resilient marsh reconstruction and restoration based on lesson-learned from natural ecosystems (e.g., through optimal colonization strategies).
SISTER includes advanced field monitoring, laboratory investigations and numerical modelling within six Work Packages.
Three specific objectives (SO) drive the whole project and are embedded into the work plan:
SO1 assess the role of the coupled dynamics between surface and subsurface processes to study the formation and the long-term evolution of transitional environments under external forcing factors, e.g., SLR.
SO2 determine the geotechnical properties of shallow soils where plant roots are present through experimental laboratory and field tests.
SO3 quantify the impacts of the new evidence gained from SO1 and SO2 on the future evolution of transitional environments under nature-based solutions and climate change.



STARTING DATE: 20/12/2022
ENDING: 19/12/2024
DURATION: 24 months


GRANT AMOUNT: € 150.000,00


RESEARCHER: dott.ssa Claudia Zoccarato


WEBSITE: https://www.preservewetlands.eu/sister-project/