The influence of rock pool morphometry on floral species diversity

Abstract

The aim of this study is to determine if floral species richness of temporary freshwater rock pools is dependent on basin morphometry or rock pool proximity. 59 pools were observed at San Pawl Tat-Tarġa during December 2019 and January 2020. The plant species in each pool were recorded in terms of presence/absence. The morphometric characteristics of the pools that were noted were the maximum water depth, maximum sediment depth and surface area. GPS coordinates for each pool were also noted. The results showed that surface area and water depth were the only morphometric factors that showed significant correlation with species richness. Spatial proximity did not influence the species richness of the rock pools, implying that at a local scale, basin morphometry has more of an influence than the spatial distance between pools. The most common lifeforms were hemicryptophytes, followed by therophytes and hydrophytes. This may be due to the anomalous wet season that provided shorter hydroperiods than normal causing the ecotone zone of rock pools to be broader due to the shorter than average wet season.