Photosynthetic parameters obtained from the adjustment of the model equation of Smith and Talling [15][16] to the observed P-E data for Zostera marina and Cymodocea nodosa.

Zostera marina and Cymodocea nodosa plants submitted to shading treatments of 24, 40 and 75% of naturally available photosynthetically active radiation (CTRL). Values are means ± se (n = 5, pPm is the maximum photosynthetic rate (mg O2 µmol ChlT−1h−1), α is the ascending slope of the light response curves at limiting PPFDs (mg O2 µmol ChlT−1h−1 (µmol quanta m−2s−1)−1), Ik is the saturation irradiance (µmol quanta m−2s−1) and r2 is the coefficient of determination of the model adjustment to the data. Different letters indicate significant differences between treatments,*indicates differences between species (p