RELATIONSHIP BETWEEN BIOMASS AND SURFACE-AREA OF 6 SUBMERGED AQUATIC PLANT-SPECIES

Mathematical relationships relating the biomass to the surface area of Elodea canadensis Michx., Myriophyllum spicatum L., Nitellopsis obtus a (Desv.) J.Gr., Potamogeton lucens L., Potamogeton pectinatus L. and Poramogeton perfoliatus L. were developed. The methods leading to thes e relations are presented for plants from Lake Geneva (Switzerland). R esults include three sets of data for each species: leaves, stems and whole plant. Differences were evidenced according to plant species; fo r a same biomass E. canadensis and M. spicatum offered the highest sur face area, P. pectinatus and N. obtusa the lowest. For 1.0 g dry weigh t of whole plant, the surface area was 1255 cm(2) for E. canadensis, 1 205 cm(2) for M. spicatum, 560 cm(2) for N. obtusa, 653 cm(2) for P. l ucens, 500 cm(2) for P. pectinatus, and 762 cm(2) for P. perfoliatus, Plants with dissected morphology did not necessarily offer the largest surface area per unit biomass.