Parametric Assessment of Macrophytes Ecological Niches in Solving Problems of Sand Quarry Lakes Phytomelioration

Abstract

Technogenic reservoirs, i.e., sand quarry lakes, appear when sand is extracted under the water column by dredgers or as a result of flooding of quarries. Studies of such reservoirs in the territory of Small Polissia (Ukraine) have shown that the devastated shoreline is like a neo-ecotope formed in the ecotone zone between the water environment of such reservoirs and natural areas upon completion of their operation. Changes in the ecotope within this zone lead to the formation of ecological niches with a set of new specific factors characteristic of aquatic and near-shore vegetation. It has been determined that the fundamental niche of macrophytes in the littoral area of sand quarry lakes in the conditions of Small Polissia is determined by the following parameters: illumination 2500-90000 lux; depth 0–5 m; and trophicity (humus content) – 0-5 %. The realized niches differ for plants of different ecological groups and make up about 50 % for helophytes, about 20 % for pleistophytes, and about 70 % for hydatophytes of the fundamental niche of aquatic vegetation. The volume of space in which the niches of all types of macrophytes in the technogenic lakes of Small Polissia overlay is 10%. The maximum overlay of niches is characteristic of areas covering a combination of factors in terms of illumination (in summer) 15000-90000 lux and depths of 1.3–2.8 m, which creates conditions for the formation of three-tiered phytocoenoses. The niche of submerged plants is the largest, which indicates their highly competitive potential, which is limited mainly by the illumination parameter. Under such conditions, the rapid development of submerged vegetation in the future may lead to the accumulation of its biomass and bogginess, which will limit the use of sand quarry lakes for recreational and other types of nature management. Phytomeliorative tree planting around sand quarry lakes is proposed to regulate illumination as a parameter of the ecological niche of submerged plants. Doi: 10.28991/HEF-2022-03-04-02 Full Text: PDF