Submerged vegetation in shallow lakes

Abstract

In submerged plants, shoots and leaves are situated within the water columns. The plants are adapted to life below the water surface by a number of morphological (e.g., reduced supporting tissues, finely dissected leaves) and physiological adaptations (shade adaptation in photosynthesis). One of the most important factors limiting photosynthesis is assimilation of inorganic carbon which is taken up either as free carbon dioxide or bicarbonate from the water phase. In isoetids, a life-form with rosette leaves typical for softwater lakes, sediments serve as source for carbon dioxide. Ground-dwelling plants like isoetids and stoneworts are sensitive against eutrophication because of light limitation, while erect elodeids and especially canopyforming species are more tolerant.