Effects of salinity, light and nutrients on photosynthesis of sterile Ulva pertusa

The effects of salinity, irradiance and nutrients on photosynthetic oxygen production rate of Ulva pertusa (sterile type) were studied. The results showed that the photosynthetic rate was influenced by salinity, the oxygen production rate was higher at salinity 20ppt under irradiance 2710 lx. The maximum oxygen production rate (P sub(m)), light saturation constant I sub(S)) and compensation light intensity (I sub(C)) were 79.62 O sub(2), gamma /cm super(2) times h, 191.08 mu E/m super(2) times s, 10.12 mu E/m super(2) times s, respectively. The nutrients (NH sub(4) super(+)-N, NO sub(2) super(-)-N, PO sub(4) super(3-)-P) uptake of U. pertusa could be described by Michaelis-Menten Model. Ammonia is toxic to U. pertusa at concentration above 0.07 mmol/L under lower irradiance (106 lx).