This product (slw) was doubled because a single sorus of approximately equal area occurs on both sides of a sporophyll (Neushul 1959).
A large decrease in sorus area and in the number of fronds per individual was observed immediately following a large storm in the 30 permanently marked Macrocystis.
In contrast to Macrocystis, Pterygophora reproduces seasonally (late fall and winter) and the amount of sorus area on an individual does not change appreciably during the reproductive season (Reed et al.
a change in sorus area or sporangium density for Macrocystis and Pterygophora, respectively), and e is the expected number of individuals showing the same directional change in reproductive condition under conditions of asynchrony.
Episodes of decrease in mean sorus area (indicating that the release of mature spores was greater than the production of new spores, which hereafter is defined as net spore release) varied in duration from as little as 1 wk (April 1994) to as much as 2 mo (June to August 1993 and January to March 1994).
Mean sorus area steadily increased in these individuals until mid-January 1993, when an abrupt 50% decline in mean sorus area was observed during a single sample period [ILLUSTRATION FOR FIGURE 2A OMITTED].
Total sorus area was estimated in two ways: sorus area per plant and sorus area scaled to plant size.
2] core was taken from the darkest portion of the sorus.
Simple linear regression was used to determine if temperature explained variation in sorus area.
Similarity in sorus area, chemical composition, and viability among sites was assessed quantitatively as Pearson product-moment correlation coefficients calculated for all between-site comparisons.
Estimates of sorus area per frond indicate that Macrocystis produces two large crops of spores during most years [ILLUSTRATION FOR FIGURE 2A OMITTED].