IMIS

Z. notei was collected in six areas distributed along the Mira channel of the Ria de Aveiro in nine visits over the course of a year. In each area, four corers were randomly collected along a transect of 5 meters. At the laboratory, corers were cleaned from sediments to measure seagrass biometrics. To determine the vegetative shoot density the vertical shoots of each corer were counted. Four vertical vegetative shoots with apparently healthy leaves and roots were randomly chosen in each corer to measure leaves per shoot, leaf width and leaf surface area. The average value of those four shoots was assigned for each corer. Leaves per shoot was calculated by counting the number of leaves in each shoot. Leaf width was measured with a millimeter caliper. The leaf surface area was calculated by dividing the total leaf area per shoot (leaf length x leaf width) by the number of leaves per shoot. • Shoot density / shoot per square metre / Counting number of shoots in a surface area (n=4) • Leaf width / centimetre / Measuring with a tape measure (n=4) • Leaf area / Area surface / Multiplying the leaf width by the sum of the leaf length per vertical shoot and dividing it by the total number of leaves per shoot (n=4) • Leaves per shoot / Number of leaves per shoot / Counting the number leaves per shoot (n=4)