The Ulva spp. Conundrum: What Does the Ecophysiology of Southern Atlantic Specimens Tell Us?

Table 1

Four-way analyses of variance of the photosynthetic capacities (based on the effective quantum yield of the PSII measurements) of three species of Ulva (orthogonal, fixed) that were incubated under different nutrient (orthogonal, fixed, three levels) and temperature (orthogonal, fixed, two levels) conditions. Plot: Erlenmeyer flasks where individuals were incubated (random and nested in the interaction of factors 1 and 2, two levels). SS is sums of squares; DF is degrees freedom; MS is mean of square and P-value <0.05.

Source	SS	DF	MS	F	P
Species (Sp)	0.0003	2	0.0001	0.18	0.84
Temperature (Te)	0.0129	1	0.0129	9.40	0.02
Nutrient (Nu)	0.0018	2	0.0009	0.64	0.56
Plot (Te×Nu)	0.0082	6	0.0014	2.29	0.04
Sp×Te	0.0072	2	0.0036	4.67	0.03
Sp×Nu	0.0082	4	0.0020	2.64	0.09
Sp×Plot (Te×Nu)	0.0093	12	0.0008	1.29	0.23
Te×Nu	0.0032	2	0.0016	1.15	0.38
Sp×Te×Nu	0.0081	4	0.0020	2.63	0.09
residual	0.0861	144	0.0006
total	0.1452	179