Identification of plate-forme à vasques on a temperate shore platform? Quantitative analysis of morphology and relationships at Bembridge, Isle of Wight

Enigmatic shallow vasques-type pools are identified for the first time on a temperate limestone shore platform. Like their counterparts found in tropical and Mediterranean climatic regions the pools occupy the intertidal zone and are separated from each other by raised ridges that facilitate the retention of tidal water. Ebb tidal water drains via low points in the ridges flowing through an interconnected network of pools towards the platform edge. The formative processes associated with ridge formation are generally attributed to bioconstruction or bioerosion. We assert that the adopted ridge forming processes differ between geographic location based primarily on regional climate which restricts the presence of bioconstructing organisms. Additionally, the direction of water flow through the pool network is predetermined by the shore platform gradient which in turn shapes pool morphology via the process of coalescence. Further interpretation and relationships are drawn from field observations and the analysis of a comprehensive set of morphometric measurements of 24 pools derived from field surveys using Differential Global Positioning Navigation Satellite System (DGNSS) and aerial image analysis. The paper quantifies the morphology, geometry and distribution of the pools providing a baseline protocol to inter-compare similar landforms. We attempt to define the relationships governing form and occurrence and identify surface topography and water flow as key components in defining the geomorphology at the site. We propose a theory for pool network evolution which highlights the respective recession rates of the landward cliff and platform edge as significant in maintaining this unique and valuable intertidal habitat with national and European conservation designations.