Systems: An Autecological Perspective

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Systems An Autecological Perspective

• What is the perspective the underlying
  physiology enabling one to understand the system.
• Systems we will examine in detail
• Riparian
• Temperate rainforest
• Old-growth
• Sub-alpine
• Link with Jim Agees course
• Link with Kern Ewings historical wetland course

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Riparian and Wetland Systems

• Definition Wetland lands where saturation with
  water is the dominant factor determining the
  nature of soil development the types of plant
  and animal communities living in the soil and on
  its surface (Cowardin 1979, EPA). Include
  swamps, marshes, bogs, etc.
• Definition Riparian Zone entire linear strip of
  land on either side of a river or stream
  including riparian wetlands.

References http//www.epa.gov/owow/wetlands/
http//www.nwi.fws.gov/bha/ http//www.cfr.washin
gton.edu/Riparian/
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Riparian Systems Closer Look

• Riparian zone is characterized by vegetation that
  responds to the stresses opportunities provided
  by being constantly to periodically wet (or in
  the groundwater fringe).

Stresses Low oxygen, negative redox potential,
mechanical, sedimentation. Soils with sufficient
oxygen are red or orange (Fe3) whereas anaerobic
soils are deficient in oxygen are gray (Fe2).
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Riparian Areas Expanded Definition

• Riparian habitats, at the interface between wet
  and dry systems, are defined by the plants that
  inhabit them. Riparian plants depend on an intact
  hydrological regime where groundwater is
  maintained and natural surface flows occur.
• Stresses, previously defined, are a critical part
  of maintaining the vegetation one finds -
  establish habitat, create new habitat and
  maintain vegetation

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Riparian Areas
1937
2000
Interaction between water vegetation Interaction
between humans water regimes
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Environment Stress Background

• Definition An environmental factor causing a
  decrease in productivity, survival or
  reproduction.
• Stresses are rarely absent the control is the
  exception.
• Stresses rarely occur singly.
• Plants are able to resist stresses.
• Plants acclimate to stress

• Abiotic stresses
• Light
• Water too much, too little
• Low oxygen
• Nutrients
• Temperature hot, cold
• Mechanical Wind, ice
• Air pollution

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Environmental Stress Resistance

• Can use a physical analogy
• Modulus of elasticity strain/stress resistance

Plastic
Elastic
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Riparian Stresses

• Low oxygen
• Avoid oxygen stress move oxygen to the roots,
  grow roots near the water - air interface
• Tolerate O2 stress
• Examples

• Mechanical
• Avoid
• Tolerate

• Redox potential
• Avoid
• Tolerate

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Riparian vs. upland systems
Example with box elder (Acer negundo)

• Dawson study

• Understand stable isotope

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Riparian Systems Human impacts

• Removal of beavers
• Removal of wood
• Splash dams
• Diking and channelization
• Exotic species
• Dams
• Changes in infiltration
• Rain on snow
• Climate change

Fantastic web site
http//www.cpluhna.nau.edu/index.htm