Acta Univ Latv (2006) 710: 53–79

Biological basis of biological diversity: physiological adaptations of plants to heterogeneous habitats along a sea coast

Abstract

To understand the mechanisms of adaptations to heterogeneous habitats along a sea coast, information is needed on the causal character of phenomena in the sequence: environmental factors » adaptive plant features » endogenous control mechanism. Abiotic conditions on the sea coast form a unique environment: sand burial, high temperature, soil salinity, soil flooding. The responses of coastal plants to these conditions are analyzed in order to define possible mechanisms of adaptation. Special attention is given to the cellular mechanisms of protection of photosynthetic machinery and antioxidative protection of cellular constituents. Hormonal and cellular control mechanisms of putative adaptive responses are analyzed. Several characteristics that may possess adaptive significance are discussed e.a. phenotypic plasticity and clonality, seed dormancy, mycorrhizal symbiosis.