(full paper is archived in the Miller Library)
Title: Individual stipe strength of Macrocystis pyrifera
Student Author(s): Hagberg, Theresa
Veit, Allison
Faculty Advisor(s): Pearse, John
Pages: 33
Location: Senior Thesis UC Santa Cruz
Date: April 1994
Abstract: We hypothesize that a kelp plant adapted to lessen
the stipe strength prior to winter storms resulting in canopy removal
which increases the probability of survivorship of the entire kelp
plant. To test this hypothesize we measured the stipe strength of
Macrocystis pyrifera, this study mesured the stress needed to break
an individual stipe in the winter season and compared it to the
summer season. The following observations were made: (1) Less stress
is needed to break a piece of kelp in the winter than in the summer.
(2) The diameter of the kelp stipe may or may not be a factor
affecting the stress needed to break the kelp stipe. (3) The length
of the kelp frond is not a factor affecting the stress needed to
break the kelp stipe. (4) The kelp stipe stretches 1/4-1/3 of its
original length before it breaks. In the ocean the hydrodynamic
forces; drag, lift, buoyancy, and acceleration play key roles which
affect the kelp forest community. Many physical and biological
processes active in nature were unaccountable for in this
experiment.