Age, Height, and Annual Growth

Total length and age of algae were significantly correlated (p = .0006) when samples were compared regardless of zone. Average total length of A. nodosum (p = .028) and age of the alga (p = .009) dependent on zone were also statistically significant. In both cases, the upper zone differed from either of the other two lower zones. Average growth per year and growth this year were examined, but not found to be statistically significant. This would indicate that total length of the algae from different zones is influenced more by age, and thus growth accumulation over many years, than growth in a given year.

Pigment Concentrations

The concentrations of chlorophyll a and the accessory pigments, chlorophyll c and fucoxanthin, as well as total pigment concentration of algae from the three different intertidal zones were compared. For each pigment, the average total per sample, as well as average concentrations from the basal most portions of the algae and the apical tips were calculated. The concentrations of chlorophyll c (ranging from 4.5 mg/g fresh weight – 23 mg/g fresh weight) are on a much high scale than those of chlorophyll a and fucoxanthin (ranging between .031 mg/g fresh weight - .23 mg/g fresh weight), thus making the total pigment concentrations very closely related to the chlorophyll c concentrations, which is displayed in the similarities between the two graphs, as well as the similar p-values. There were significant differences between portions of the algae for both chlorophyll a (F _{1, 1} = 8.52, p = .0075) and chlorophyll c (F _{1, 1} = 20.30, p = .0002).

Concentrations of fucoxanthin were similar in total sample, apical tip, and basal portion in both the lower and middle intertidal zones, but differed in the upper intertidal zone. As would be expected, concentration per total algal sample was between basal and apical concentrations in all four graphs.