BOTANY WITH BASICS OF HYDROBOTANY (AQUATIC PLANTS OF UKRAINE) - B.Ye. Yakubenko - 2011

VI. PLANT KINGDOM SYSTEM

LOWER SPORE PLANTS

GENERAL CHARACTERISTICS AND FEATURES

Ecological features of algae in aquatic habitats and factors of their development

Algae are photoautotrophic organisms; therefore, the leading factors influencing their development are light, Temperature, the presence of a liquid Water environment, as well as sources of oxygen, mineral, and organic substances. As plants, these organisms inhabit virtually all possible habitats in the Earth's hydrosphere, atmosphere, and lithosphere. They can be found in water, soil, and on its surface, on tree bark, the walls of wooden and stone buildings, steel and epoxy resin products, or fabrics, among other places.

The development and growth of algae are driven by a variety of factors of different nature. Factors influencing algal development are divided into abiotic (unrelated to The activity of living organisms) and biotic (caused by their activity). Abiotic factors include temperature, light, physical and Chemical properties of water and substrate, condition and composition of air masses (which is especially important for aerophytic algae living outside the aquatic environment), and several others. Biotic factors include trophic and allelopathic interactions, competition, Symbiosis, etc.

A special place in the existence of algae belongs to anthropogenic factors (anthropogenic eutrophication, emissions of toxic industrial waste into the aquatic and atmospheric environments, etc.). Most factors, especially abiotic ones, are limiting, meaning they can restrict The Development of algae. The development of organisms, including algae, depends on the composition of necessary substances in the habitat, The values of physical factors, and the range of tolerance (resistance) of the organisms themselves to changes in these or other environmental conditions.

The threshold at which a certain factor can act as limiting varies across different taxonomic groups and specific taxa of algae. In aquatic ecosystems, limiting factors include temperature, transparency, salt and mineral composition of water, presence of currents, concentration of oxygen, carbon dioxide, and nutrients. In terrestrial habitats, among the main limiting factors are climatic ones—temperature, humidity, light, etc.—as well as the Composition and Structure of the substrate. These two groups of factors, together with population interactions, determine The Nature of terrestrial communities and ecosystems.