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Barrier retreat can occur due to in-place drowning, overstepping or rollover, depending on the interplay of controls such as sea-level rise, sediment supply, coastal hydrodynamic regime and topography. Offshore sedimentary archives of barriers active during rapid Holocene sea-level rise provide important records of marine transgression, which are vital analogues to support appropriate mitigation strategies for future coastal realignment under projected relative sea-level rise scenarios. This study analyses the sedimentary archive at Dogger Bank, which is a formerly-glaciated area in the North Sea. Dogger Bank experienced marine transgression due to Early Holocene rapid relative sea-level rise. An integrated dataset of vibrocores and high-resolution seismic reflection data permits a stratigraphic framework to be established, which reveals the buried coastal geomorphology of the southern Dogger Bank for the first time. A transgressive stratigraphy was identified, comprising a topographically complicated basal glacial and terrestrial succession, overlain by two phases of barrier and tidal mudflat deposition, prior to shallow marine sedimentation. Barrier phase A was a recurved barrier drowned in place, and discontinuously overstepped to barrier phase B, which experienced continuous overstepping. By linking barrier elevations to relative sea-level curves, the timing of each barrier phase was established. Both barrier phases retreated during periods of rapid sea-level rise with abundant sediment supply. Coastal hydrodynamics (increasing wave energy) and antecedent topography with spatially variable accommodation are suggested to be the main reason for differing retreat mechanisms, rather than the rate of sea-level rise. Antecedent coastal geomorphology plays a critical role in erosional and depositional patterns during transgression, and therefore on the timing, rate and location of marine inundation, which needs to be included in models that aim to forecast hazards in coastal areas. • Early Holocene coastal geomorphology of Dogger Bank revealed for the first time through vibrocore and seismic data. • Two distinct phases of barrier retreat are recorded in the sedimentary archive. • Discontinuous, rapid and continuous, slower overstepping is observed during similar sea-level rise and sediment supply. • Rate of sea-level rise is a driver but not a main control on barrier retreat. • Antecedent topography and changing coastal hydrodynamics are the main controls on style of overstepping [ABSTRACT FROM AUTHOR]

Global change threatens invertebrate biodiversity and its central role in numerous ecosystem functions and services. Functional trait analyses have been advocated to uncover global mechanisms behind biodiversity responses to environmental change, but the application of this approach for invertebrates is underdeveloped relative to other organism groups. From an evaluation of 363 records comprising >1.23 million invertebrates collected from rivers across nine biogeographic regions on three continents, consistent responses of community trait composition and diversity to replicated gradients of reduced glacier cover are demonstrated. After accounting for a systematic regional effect of latitude, the processes shaping river invertebrate functional diversity are globally consistent. Analyses nested within individual regions identified an increase in functional diversity as glacier cover decreases. Community assembly models demonstrated that dispersal limitation was the dominant process underlying these patterns, although environmental filtering was also evident in highly glacierized basins. These findings indicate that predictable mechanisms govern river invertebrate community responses to decreasing glacier cover globally.