Oral Presentation Australian Freshwater Sciences Society Conference 2022

Can we define the bounds of resilient variability in dynamic wetland systems? A conceptual case study using non-woody vegetation responses (#41)

Cherie J Campbell 1 , Ross M Thompson 1 , Samantha J Capon 2 , Fiona J Dyer 1
  1. Centre For Applied Water Science, Institute for Applied Ecology, University of Canberra, Canberra, ACT, Australia
  2. Australian Rivers Institute, Griffith University, Nathan, QLD, Australia

Floodplain-wetlands are dynamic. Natural wet-dry variability means these systems cycle through wetting-wet-drying-dry phases. Plants and vegetation communities in floodplain-wetland systems have various mechanisms for coping with patterns of wetting and drying – for example the ability to resist or respond to transitions between the hydrological phases – i.e. their resilience. Given these systems are naturally dynamic, can we untangle natural variability from a loss of resilience? Can we define the bounds of resilience for non-woody vegetation as it transitions through natural wet-dry cycles? Here, we explore the characteristics of five broad non-woody vegetation types and hypothesise vegetation responses, considering composition, structure and processes, through all phases of wetting-wet-drying-dry cycles, under ‘exemplar’, drier and wetter hydrological conditions. We apply the idea of adaptive and maladaptive spaces to help frame the bounds of resilience. We provide a preliminary case study using data from the Flow-MER program. We believe our conceptualisation can help define expected outcomes (e.g. what are the characteristics of a functioning reed bed?), bounds of resilience (e.g. when is a reed bed no longer a reed bed?) and restoration goals (e.g. how do we reinstate a reed bed?).