Anatomical features of the leaves of Honckenya peploides and Cochlearia officinalis in the supralittoral and littoral zones of the Barents Sea
E. O. Kazakova1, I. V. Ryzhik1,2
1Murmansk Marine Biological Institute of RAS, Murmansk, Russia
2Murmansk Arctic State University, Murmansk, Russia
Keywords: Cochlearia officinalis, Honckenya peploides, anatomy, littoral, supralittoral
Abstract
This article examines the problem of environmental adaptations of plants to the conditions of the supralittoral and littoral of the Barents Sea coast. The article is devoted to a comprehensive study of the anatomical features of the leaf blades Honckenya peploides (L.) и Cochlearia officinalis (L.). The study used plants collected in the budding phase. The collected leaves were fixed in 70 % ethanol. Measurements of the elements of the anatomical structure were carried out using a light microscope. It has been established that the environmental conditions of the coastal zone determine the formation of specific anatomical features in these plants. H. peploides is characterized as a more highly specialized species with pronounced xeromorphic features: amphistomatic leaves, a developed cuticle layer and an isolateral mesophyll structure. C. officinalis is a heterogeneous species. In supralittoral conditions, the plant exhibits mesomorphic features such as sinuous cell walls, hypostomatic leaves, clear differentiation of the mesophyll into columnar and spongy layers, as well as the presence of large intercellular cells in the spongy mesophyll. On the upper littoral, C. officinalis acquires xeromorphic features: an increase in the thickness of the leaf and cuticle, as well as amphistomaticity. Probably, the combination of meso- and xeromorphic features favored the distribution of C. officinalis in a wider range of the coastal zone. The data obtained confirm the close connection of the anatomical structure of the leaves with environmental conditions and reflect the specific adaptations of each species to the environment.
|
