Life strategies of dominant plant species in the White Sea littoral zone

УДК 582.933:574.3

Abstract

The study of the mechanisms of plant adaptation to the unstable conditions of the littoral zone of tidal seas is a poorly studied topic. The goal is to identify the morphological and anatomical adaptive characters of Triglochin maritima L. and Plantago maritima L. and their life strategy. The study was carried out on the Pomeranian coast of the western coast of the White Sea, in the vicinity of the village Rastnavolok, Belomorsky district of the Republic of Karelia in 2020-2022. T. maritima and P maritima dominate in the plant communities of the littoral zone, occupying similar biotopes. It was revealed that in P. maritima under such conditions two biomorphs are formed (rosette and upper rosette), and the integumentary and mechanical tissues of the root and rosette shoots are well developed. This is an adaptation to the mobility of the soil substrate and water mass during tidal surges, to falling asleep with soil during tides and storms. Succulence (development of water-storing parenchyma in leaves) is an adaptation to water loss under salinity conditions. In T. maritima, adaptive traits are the large production capacity of the underground part of the clone, the development of mechanical tissue in the rhizome and in the sheaths of photosynthesizing and dead leaves. The rhizome is ring-shaped with shortened internodes, where sclerotized sheaths of dead leaves are preserved, provides strong rooting in a moving substrate, the implementation of the «phalanx» life strategy and ecosystem engineering function in the biotope.