Ecophysiology and Crassulacean Acid Metabolism of Tropical Epiphytes

  • Katia SilveraEmail author
  • Eloisa Lasso
Part of the Tree Physiology book series (TREE, volume 6)


Epiphytes are plants that germinate and grow upon other plants without contact with mineral soil and without parasitizing their host plant. Therefore, they derive nutrients and water from the environment. Epiphytes are primarily tropical in distribution and may be the most species-rich life form in very wet rainforest sites, constituting about 10 % of all vascular plants. Nearly 80 % of all vascular epiphytes belong to one of three families: Orchidaceae (orchids), Bromeliaceae (bromeliads), and Polypodiaceae (ferns). Orchids in particular, are the most species rich in epiphytes. In this review, information on the ecophysiology of vascular epiphytes is presented, in an attempt to find patterns that explain the ecophysiological adaptations of canopy living. We highlight the ecophysiology of orchids and bromeliads, and whenever possible, provide insight into other epiphytic families. We discuss morphological, anatomical and physiological novelties that epiphytes have evolved to face the challenges of living in the canopy, including adaptations to increase water capture, to facilitate water storage or to reduce water loss. Because epiphytes are particularly susceptible to climate change, and can be monitored as a component of forest health, we also consider their distribution and physiological responses to climate change as a key aspect of conservation programs.


Epiphytes Crassulacean acid metabolism (CAM) Bromeliaceae Orchidaceae Conservation 



We dedicate this chapter to the memory of Mónica Mejía-Chang, a great friend and passionate epiphyte and bromeliad researcher in Panama. Her infectious personality and enthusiasm for life was reflected in her work and radiated throughout her life. We kindly acknowledge John Cushman and artist Kirah Van Sickle for providing figure 2. This work is supported in part by funding from the National Science Foundation (Award DEB 1442199 to KS), the Smithsonian Tropical Research Institute Tupper Fellowship (to KS), and the Panamanian Secretaría Nacional de Ciencia, Tecnología e Innovación (SENACYT to KS). This publication was also made possible by the Colombian Fondo de Apoyo a Profesores Asistentes (FAPA to EL) from the Universidad de Los Andes , Bogotá.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Smithsonian Tropical Research InstituteBalboaRepublic of Panama
  2. 2.Department of Botany and Plant SciencesUniversity of California RiversideRiversideUSA
  3. 3.Departamento de Ciencias BiológicasUniversidad de Los AndesBogotáColombia

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