Speed Presentation 2024 Australian Marine Sciences Association Annual Meeting combined with NZMSS

Tidal reconnection and establishment of coastal vegetation: Assessment of key factors influencing soil surface elevation dynamics during restoration (#289)

Vicki Bennion 1 , Jack Hill 1 , Valerie Kwan 1 , Alex Pearse 1 , Alice Twomey 1 , Catherine Lovelock 1
  1. School of the Environment, The University of Queensland, Brisbane, QLD, Australia

Coastal restoration projects are increasing as the ecological importance of these ecosystems become more apparent. With sea-level rise, coastal agricultural land that was drained and closed off from the tide decades ago are becoming available for restoration of coastal ecosystems. Conversion back to coastal wetlands usually involves reconnecting tidal flows through the modification or removal of tidal gates. Knowledge of the links between differing levels of hydrological connectivity over landscapes, vegetation growth and soil surface elevation increments is limited. Here we assessed how these factors combined to create what is now known as the Yandina Wetlands. The land was first purchased by the Sunshine Coast Council in 2010 with tidal re-connection occurring through opening tidal gates. Over time adaptive management strategies aimed at limiting tidal ingress onto adjacent land has led to high variation in tidal connectivity across the landscape. Monitoring of hydrological, vegetative and soil surface elevation throughout the past four years has enabled an understanding of the factors driving the establishment of mangroves, open water areas for birds and fish and supratidal forests. This research will assist in future coastal restoration practices in drained landscapes of the region.