Aquatic Ranunculus communities in the northern hemisphere: A global review

Abstract

This study offers a general review of aquatic ranunculi communities in the northern hemisphere, and includes aspects of their ecology, syntaxonomy and distribution. White-flowered ranunculi communities (Ranunculus subgenus Batrachium) grow in a wide range of habitats, including different types of water regime (still and flowing waters; permanent and seasonal waters) and nutrient states. They are mainly found in Eurasia. High richness is detected in Western Europe and the Mediterranean area of heterophyllous and laminar-leaved species, and in Asia of species with only dissected leaves. The western centre of the heterophyllous species has been related to waters with low mineralization and oscillation events occurring between the Mediterranean and Temperate climates. Yellow-flowered ranunculi communities (R. Xanthobatrachium) include heterophyllous species with a tendency to helophytism. They also are found in a wide range of aquatic habitats. There is an uneven degree of knowledge on the ecology of aquatic ranunculi communities, and further research is required into aquatic ranunculi habitats in Asia and North America.