Algal associations in the Mojave Desert

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Algal associations in the Mojave Desert

• J. A. Nienow
• Valdosta State University

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Desert algae
Cyanobacteria
Green Algae
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Desert algal associations
Biological soil crusts
Hypolithic algae
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Basic questions/areas of research

• Biodiversity/composition of the two major types
  of associationsthe same or different
• Responses/adaptations of each association to the
  environmentphotosynthesis
• Pattern formation in biological soil crusts in
  relation to climate changedocumenting and
  analyzing patterns in nature

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Photosynthesis and fluorescence
Flow of energy and electrons
Campbell Reece. 2005. Biology.
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Photosynthesis and fluorescence
Flow of energy and electrons
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Parameters measured by the PAM fluorometer

• Baseline fluorescence (Fo)
• Fluorescence under saturating light conditions
  (Fm)
• Photosynthetic yield (Y Fm Fo/ Fm)

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Physiological response of terrestrial algae to
wetting
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Patterns in biological soil crusts
Patterns from photographs
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Patterns in biological soil crusts
Patterns from measurements of background
fluorescence (Fo)