ANATOMICAL-HISTOLOGICAL OBSERVATIONS CONDUCTED ON AQUATIC FERNS IN THE DANUBE DELTA

Abstract

This paper analyses aquatic ferns from the genera Azolla Lam., Marsilea L. and Salvinia Séguier, which occur in the Danube Delta, Romania, and comprises a series of anatomical and histological observations of taxonomical, chorological and eco-morphological importance. The research conducted on specimens collected between 2005-2013 from the natural habitats of the Danube Delta, but also from the extra-deltaic artificial habitats have enabled: i) a reconsideration of some chorological aspects regarding the species of the genus Azolla in Romania; ii) a greater understanding of the adaptive plasticity relative to the factor water for the taxon Marsilea quadrifolia L. collected from natural and artificial habitats; iii) the enrichment of the data regarding the structural characteristics of the taxon Salvinia natans (L.) All., particularly around the adaptive elements associated with living on the surface of the water.

Keywords

• adaptability
• anatomy
• aquatic ferns
• chorology
• taxonomy