Understanding how aquatic communities respond to alternating wetting and drying is a key challenge for managing dryland river–floodplain systems. This study presents a developing and practical framework to describe and compare wetland invertebrate community responses across inland New South Wales rivers.
Invertebrate datasets from multiple valleys were standardised to consistent taxonomic levels and used to track changes in alpha diversity, defined here as within-wetland taxonomic richness at a point in time. To enable comparison of diversity trajectory shape between systems with different sampling histories, each time series was converted to a relative timeline representing progression from inundation to drying.
Disturbance events were identified where declines in diversity indicated system “resets,” allowing time series to be divided into discrete ecological cycles. Within these cycles, broadly consistent stages emerge, including an early colonisation phase with increasing diversity, a peak phase, and a late-stage decline.
Clear non-linear trajectories were observed in some systems, with diversity typically peaking midway through the cycle, while others showed weak or negligible responses. Variation among wetlands was expressed in the strength, timing, and completeness of trajectories, reflecting both ecological variability and uneven sampling coverage.
These results represent the current state of a developing modelling environment, with both the underlying wetland depth modelling and taxonomic decision framework still being refined.
Future work will focus on identifying common modal or multimodal diversity trajectories and linking these to functional group responses, providing a pathway to mechanistically interpret ecological change and improve flow–ecology relationships for adaptive water management.